MSCBOT-603.pdf

MSCBOT-603 M.Sc. III Semester PLANT RESOURCE UTILIZATION AND CONSERVATION DEPARTMENT OF BOTANY SCHOOL OF SCIENCES UTTARAKHAND OPEN UNIVERSITY PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603...

MSCBOT-603 M.Sc. III Semester PLANT RESOURCE UTILIZATION AND CONSERVATION DEPARTMENT OF BOTANY SCHOOL OF SCIENCES UTTARAKHAND OPEN UNIVERSITY PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 MSCBOT-603 PLANT RESOURCE UTILIZATION AND CONSERVATION DEPARTMENT OF BOTANY SCHOOL OF SCIENCES UTTARAKHAND OPEN UNIVERSITY Phone No. 05946-261122, 261123 Toll free No. 18001804025 Fax No. 05946-264232, E. mail [email protected] htpp://uou.ac.in UTTARAKHAND OPEN UNIVERSITY Page 1 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 Expert Committee Prof. J. C. Ghildiyal Prof. G.S. Rajwar Retired Principal Principal Government PG College Government PG College Karnprayag Augustmuni Prof. Lalit Tewari Dr. Hemant Kandpal Department of Botany School of Health Science DSB Campus, Uttarakhand Open University Kumaun University, Nainital Haldwani Dr. Pooja Juyal Department of Botany School of Sciences Uttarakhand Open University, Haldwani Board of Studies Prof. P.D. Pant Prof. S.S. Bargali Director, School of Sciences HOD, Department of Botany Uttarakhand Open University, Haldwani DSB Campus, Kumaun University, Nainital Prof. Amrita Nigam Dr. S.S. Samant School of Sciences Retd. Director IGNOU, New Delhi Himalayan Forest Research Institute (H.P) Dr. S.N. Ojha Dr. Pooja Juyal Assistant Professor Assistant Professor (AC) Department of Botany Department of Botany Uttarakhand Open University, Haldwani Uttarakhand Open University, Haldwani Dr. Kirtika Padalia Dr. Prabha Dhondiyal Assistant Professor (AC) Assistant Professor (AC) Department of Botany Department of Botany Uttarakhand Open University, Haldwani Uttarakhand Open University, Haldwani Dr. Pushpesh Joshi Assistant Professor (AC) Department of Botany Uttarakhand Open University, Haldwani UTTARAKHAND OPEN UNIVERSITY Page 2 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 Programme Coordinator Dr. S.N.Ojha Assistant Professor Department of Botany, School of Sciences Uttarakhand Open University, Haldwani, Nainital Unit Written By: Unit No. 1. Dr. Manish Tripathi 1, 2 & 6 Assistant Professor Department of Botany, SSJ Almora campus Almora University, Almora 2. Dr. Prakash Chandra Paliwal 3 Assistant Professor, Department of Botany Government PG College, Ramnagar 3. Adapted from https://egyankosh.ac.in/handle/123456789/45122 4, 5, 7, 9 & 11 https://egyankosh.ac.in/handle/123456789/83807 https://egyankosh.ac.in/handle/123456789/83804 Rap up material 4. Dr. S.N.Ojha 8 Assistant Professor Department of Botany, School of Sciences Uttarakhand Open University, Haldwani, Nainital 5. Dr. Pooja Juyal 10 Department of Botany School of Sciences Uttarakhand Open University, Haldwani, Chief Course Editor Dr. Pooja Juyal Department of Botany School of Sciences Uttarakhand Open University, Haldwani UTTARAKHAND OPEN UNIVERSITY Page 3 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 Co-Editor Dr. S.N. Ojha Dr. Kirtika Padalia Assistant Professor, Department of Botany Assistant Professor (AC) School of Sciences Department of Botany, School of Sciences, Uttarakhand Open University, Haldwani Uttarakhand Open University, Haldwani Dr. Prabha Dhondiyal Dr. Pushpesh Joshi Assistant Professor (AC) Assistant Professor (AC) Department of Botany, School of Sciences Department of Botany, School of Sciences Uttarakhand Open University, Haldwani Uttarakhand Open University, Haldwani Title : Plant Resource Utilization and Conservation ISBN No. : Copyright : Uttarakhand Open University Edition : 2022 Published By: Uttarakhand Open University, Haldwani, Nainital-263139 UTTARAKHAND OPEN UNIVERSITY Page 4 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 CONTENTS BLOCK-1 PLANT RESOURCES: FOOD VALUE PAGE NO. Unit-1 Domestication and Introduction of plants 7-29 Unit-2 Food species, Fruits and Nuts 30-71 Unit-3 Edible Oils, Species and Condiments 72-94 BLOCK-2 PLANT RESOURCES: DIVERSE VALUE PAGE NO. Unit-4 Medicinal and Aromatic Plants 96-117 Unit-5 Fodder and Fiber Crops 118-136 Unit-6 Beverages and Narcotics 137-157 Unit-7 Timber and Non-timber 158-181 Unit-8 Sugar and Starch, Energy crops 182-231 BLOCK-3 PLANT CONSERVATION PAGE NO. Unit-9 Principles of conservation 233-250 Unit-10 Strategies for in-situ conservation 251-278 Unit-11 Strategies for ex-situ conservation 279-313 UTTARAKHAND OPEN UNIVERSITY Page 5 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 BLOCK-1 PLANT RESOURCES: FOOD VALUE UTTARAKHAND OPEN UNIVERSITY Page 6 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 UNIT-1 DOMESTICATION AND INTRODUCTION OF PLANTS Contents 1.1 Objectives 1.2 Introduction 1.3 Introduction and domestication of plants 1.3.1 Purpose of Plant Introduction and Domestication 1.3.2 Procedure of Plant Introduction 1.3.3 Agencies associated to Plant Introduction in India 1.3.4 Merits and Demerits of Plant Introduction: 1.3.5 Achievements of Plant Introduction 1.4 Agricultural Origins 1.5 Origin of cultivated plants- Vavilov‘s centres of origin 1.6 Summary 1.7 Glossary 1.8 Self assessment questions 1.9 References 1.10 Suggested readings 1.11 Terminal questions UTTARAKHAND OPEN UNIVERSITY Page 7 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 1.1 OBJECTIVES This unit will help you to understand the origin, introduction and domestication of cultivated plants. This unit also describes in detail that how an individual plant species introduce to new region and acclimatized. The main objectives of this unit are:  To know about the domestication and introduction of plants.  To know the origin of cultivated plants  To know about Vavilov‘s centers of origin 1.2 INTRODUCTION The food is an essential requirement of human beings. The prehistoric humans primarily got their food from the wild edible plants but since the time passed, they started to cultivate the wild plants. The traditions of those prehistoric humans take very prominent part in the origin of cultivation of plants. The domestication of plants is the starting step in the direction of a full- fledged agricultural economy. A plant is refers to as domestic when its natural characteristics got improved too much therefore it is hard to grow and reproduce those plant without human participation. It is thought the domestication is the co-evolutionary outcome of the symbiotic relationship between humans and the plants because plants and human behaviours evolve to suit one another. The humans started harvesting of plants selectively based on some precise characteristics of plants like taste, size, colour and many more. They stored and utilize the seeds of those specific plants for further cultivation. It is believed that most of the plant were cultivated first during historical times and consequently have exceptionally poor evidence. The paleontological data is entirely unavailable for cultivated plants and archaeological information is fragmented and very poor. In the beginning of 19th century the origin of majority of the cultivated plants were unknown. No species was common to the tropical regions of the two hemispheres before cultivation. In brief, the original distribution of the cultivate species were very much uneven. There was no proper proportion in the number of plants cultivate and their needs for human. Some ancient Roman and Greek naturalists like Theophrastus, Elder, and Galen Pliny laid down systematic groundwork of wild plant domestication. Alexander von Humboldt also considered the origin of useful plants is a big secret as well. Finally, Darwin‘s evolutionary theory recommended that origin of cultivated plants take place through natural selection and repetitive hybridization. So, in this chapter we will discuss about the domestication and introduction of plants, origin of cultivated plants in detail. UTTARAKHAND OPEN UNIVERSITY Page 8 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 1.3 INTRODUCTION AND DOMESTICATION OF PLANTS What is introduction and domestication of plants? The human beings received their nutrition from others (plants and animals), therefore, they are called heteroptops in nutrition. The present day humans are evolved from herbivorous ancestors but in a while about two million years ago (viz., early Palaeolithic man), they started using hunting through weapons made by stone. Later on they began to eat roots, tubers and fruits of wild plants too. Much later, man started cultivating plants and raising animals and started a settled life. Initially their establishments have been primarily located in the river valleys and plains near river banks where plenty of water and fertile soil was accessible. By getting all these favorable conditions, it was easy to cultivate crops, resulted plentiful crop production and they became self-sufficient. It is believe that agriculture have been originated somewhere in the well irrigated highlands of the Indus, Euphrates and Nile and Tigris rivers nearly 7000-13000 years ago. A few other prehistoric sites like Tehuacan valley in modern Mexico and banks of Yellow river in modern China are also the evidences of ancient agricultural activities. Apart from this, the agriculture has begun separately in various parts of the world. So, do you ever think that how a regional cultivated crop becomes cosmopolitan in its distribution? It could become possible only due to the ―plant introduction‖ of a particular region to the other region. Let‘s make it easy to understand this concept with this example. The cultivation is called deliberately growing a plant. Foremost, those individual plants were brought into cultivation that grow fast and produce crop rapidly within a season which include the present day cereals. Cereals were originally weeds that grew in mountain areas of Asia, Africa, Europe, North and South America but now they are being cultivated in all other parts of the world due to the plant introduction. So, the plant introduction is a progression of introducing plants (a genotype or a group of genotypes) from their own environment to a new environment. This process may include new varieties of crop or the wild relatives of crop species or totally a new crop species for the area. Introduction may be classified into two categories: (a) Primary Introduction: When the introduced variety is well suitable to new environment afterward it released, devoid of any modification of genotype for commercial production is called primary introduction. Some examples of primary introduction are; dwarf wheat varieties like Lerma roja, Sonora-64, and dwarf rice varieties like ‗IR-8‘ and Taichung Native 1. (b) Secondary Introduction: When the introduced variety is subjected to the selection or used in hybridization programme with local varieties having some new characters to obtain the superior varieties called secondary introduction. For example, the varieties like ‗Kalyan Sona‘ and Sonalika of wheat have been selected from material introduced from CIMMYT, Mexico. UTTARAKHAND OPEN UNIVERSITY Page 9 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 The progression of plant introduction is the thriving observance of two imperative aspects, viz. (i) Domestication: It is a method of bringing of wild plants under cultivation by making them appropriately modified for new environment. In other words, we can say that it is the practice in which wild species have been evolved into crop plants using artificial selection of some characters. The plant domestication involves an early hybridization event followed by selective breeding. With the help of this technique now the cultivars are able to cultivate plant based on some selectively and specific characteristics like taste of the fruits, size of the flowers, colour of the flowers and fruits and so on. The domestication of plants is the starting step in the direction of a full-fledged agricultural economy. Domestication is the reflection of co-evolution where both the components (plants and humans) developing a symbiotic relationship because human and plant behavior evolve to suit one another. The process of domestication of wild edibles and introduction of plants has been going on since the prehistorical time. Some important crops of human use and their domestication information are given below (Table 1.1): Table 1.1: List of domestication of some important plants Domestication time Plant name Domesticated at Fig tree Near East 9000 BC Rice East Asia Barley, Einkorn wheat, Emmer 8500 BC Near East wheat Chick pea Anatolia 8000 BC Bottle gourd Asia Potato Andes mountain Squash Central America 7000 BC Maize Central America 6000 BC Broomcorn millet East Asia Bread wheat Near East Cassava South America 5000 BC Avacado Central America Cotton Southwest Asia 4000 BC Chilli Peppers South America Water melon, Olives Near East Cotton Peru 3500 BC Pomegranate Iran Hemp East Asia 3000 BC Cotton Meso America Cocoa South America UTTARAKHAND OPEN UNIVERSITY Page 10 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 Squash North America 2600 BC Sunflower Central America 2500 BC Sweet potato Peru 2400 BC March Elder North America 2000 BC Sorghum Africa Sunflower North America 1800 BC Pearl millet Africa 1600 BC Chocolate Mexico 1500 BC Chenopodium North America 1st century BC Egg Plant Asia 14th century AD Vanilla Central America (ii) Acclimatization: When an improved variety from distant or neighbouring area is introduced at a new area, normally it fails to express its phenotypic expression in the same manner as its native place. But later on, the growth of new plant variety accelerates and furnishes optimal phenotypic characters. In other words, now the variety becomes acclimatized to their new environment. Sometimes, the performance of a variety improves with a number of generations grown when introduce to a new environment. So, acclimatization is the capability of a plant variety to become adapted to a new edaphic and climatic condition. The process of acclimatization leads to increase the frequency of most adapted genotypes which depends on three factors: (a) Breeding system: Breeding systems referring in plants is simply called as "Who mates with whom". It is an essential aspect which determines the homozygosity, patterns of genetic diversity and genome evolution in plants. It can divide into two types; (i) Pure breeding: Breeding between pure breeds where the ancestors of both mating type have been members of a recognized breed and (ii) Cross breeding: Breeding where status of only one parent is known or breeding between two different breeds, varieties, or populations. (b) Genetic variation: Genetic variation or diversity is called as the diversity exists within different genotypes of the same species. It is required in natural selection where the organisms with environmentally preferred traits are improved which are very much competent to adapt the environmental conditions and transfer their genes to next progeny. (c) Duration of the crop: The time duration from establishment to harvesting a crop is known as duration of the crop. Its timing may differ a little depending on the growing circumstances especially water availability and solar radiation. 1.3.1 Purpose of Plant Introduction and Domestication (i) For germplasm conservation: The dissemination of high yielding varieties is one of the many reasons of a threat to old varieties to abolish from an area. Here, germplasm collection as UTTARAKHAND OPEN UNIVERSITY Page 11 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 well as conservation helps to maintain the pure line, cultivars, mutants, clones etc from as many sources as possible. (ii) Use in agriculture, forestry and industry: New varieties of plants or crops which are high quality and better production introduced from various places for use as fiber, food, medicinal, timber etc as well as the breeding material for hybridisation work. (ii) For aesthetic interest: Various ornamental plants are introduced for beautification and for aesthetic value. (iv) For studying origin and distribution: The distribution of crop plants and their various forms in different parts of the world gives an idea of their origin and evolution. 1.3.2 Procedure of Plant Introduction Plant introduction procedure consists of following steps: (i) Ways of Procurement of Plants or Germplasm: Commandeer for introduction of new varieties crop or plant should be submitted to National Bureau of Plant Genetic Resources (NBPGR) within the country or to International Bureau of Plant Genetic Resources (IBPGR). One may get the plant specimen on an exchange basis from friendly countries either directly or through Food and Agriculture Organization (FAO) or the specimen can also be purchased or obtained as free gift from individuals or organizations. (ii) Packaging and Dispatch: Any part of the plant which is utilized for the propagation of that species is called a propagule. Based upon the type of propagule, it gets cleaned from other weed- seeds and contaminants and treated with fungicides, packed carefully and dispatched so that it can reach the intention in viable condition. The propagule may be tubers, bulbs, buds, seeds, seedlings, root cuttings, suckers, stolons runners etc depending upon the plant species. (iii) Entry and Plant Quarantine: On receiving of the specimen the entry inventory, examination and checking is done by the nation for other contaminants and the presence of diseases, nematodes, insect etc. The specimen first treated with fungicides, nematicides, insecticides, and then released to the user. The general purpose of all this ‗regulatory and quarantine‘ procedures is to prevent diseases and pests from entering into the country as well as to check spreading further. (iv) Cataloguing: Subsequent to quarantine, the introduced specimen is given a number concerning place of origin, variety, species, and the data are recorded. The plant materials are classified into three groups: 1. Exotic collection – prefix ‗EC‘ 2. Indigenous collection – designated as TC‘ 3. Indigenous wild collection – marked as TW‘. UTTARAKHAND OPEN UNIVERSITY Page 12 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 (v) Evaluation: To evaluate the potential of new introductions, their performance at different substations are evaluated as well as resistance to diseases and pests are evaluated under different environments. (vi) Multiplication and Distribution: The capable newly introduced species is propagated and then released as varieties after required examinations. 1.3.3 Agencies associated to Plant Introduction in India The central plant introduction agency in India is National Bureau of Plant Genetic Resources (NBPGR), which has its headquarters at New Delhi, but has substations for testing the plant materials. NBPGR has the gene bank for long term storage and future use; it helps to assess the introduced plant material, coordinates the work of other agencies and imparts training in plant collection, introduction and maintenance in India. The Substations under NBPGR are: (i) Shimla: It represents the temperate zone of approx. 2300 m above sea level, place for germplasm collection in northern hills, station for acclimatization of material introduced from temperate zone and high altitude. (ii) Jodhpur: Exclusively meant for exploring and acclimatizing plant material for arid zone, this is under Central Arid Zone Research Institute. (iii) Amravati: This substation carries out acclimatization and multiplication of introduced material for central zone of India. (iv) Kanya Kumari: It represents the tropical zone situated at South India. (v) Shillong: This centre has been created for collection of germplasm from North-East India. Other agencies engaged for this purpose are: (i) Forest Research Institute (FRI): It situated at Dehradun, Uttarakhand. The plant introduction organization set up at the institute at looks after introduction, acclimatization, conservation and testing of forest trees. (ii) Botanical Survey of India (BSI): It is located in Kolkata, West Bangal. This body is meant for introduction of medicinal plants and also plants for botanical importance. (iii) Different Central Research Institutes as well as Agricultural Universities play the role for collection, introduction and maintenance of germplasm of crop plants. 1.3.4 Merits and Demerits of Plant Introduction: (A) Merits: i. Introduction provides completely new crop plants to a place. ii. Better yielding varieties may be originated directly or after selection or hybridisation. iii. Introduction is the most economical and quick method of crop improvement when intro- duced material can be used directly. iv. Germplasm collection, maintenance and protection of genetic variability are possible through the ways of introduction and exploration. UTTARAKHAND OPEN UNIVERSITY Page 13 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 v. Introduction of some varieties to newer areas may protect them from some diseases. (B) Demerits: i. Some disadvantages or demerits coupled with plant introduction are prologue of some transmissible diseases, pests and weeds. ii. Some weeds like Lantana, Argemone, Eichhornia, etc have also been introduced from other countries with the introduction of crop plants. iii. Some diseases like flat smut of wheat, late blight of potato, coffee rust, bunchy top of banana etc are have been introduced in India along with introduction of plant materials. iv. Many insect pests like potato tuber moth, woolly aphis of apple, fluted scale of citrus were introduced in India along with plant introduction. However, in most of the cases, the introduction of diseases, pests, insect and weeds occurred during a phase when quarantine was almost non-existent. 1.3.5 Achievements of Plant Introduction The course of introduction from the ancient times assists the entire world to achieve newer crop species to new places as well as the new varieties of crop plants. Some important achievements are: (A) New Crop Species: A number of crops have been introduced in India from outside which ar not native of India. Many cereal, fruit, oil yielding and many more economical utilized crops like maize, potato, groundnut, chillies, tea, coffee, rubber, guava, grape, pineapple etc are now cultivated in India only by introduction of all these species to India. Many ornamentals plants like Gulmohor, Phlox, Salvia, Aster are also introduced to India. (B) New Crop Varieties: (a) Selection of desirable varieties: A lot of varieties have been developed after selecting from introduced varieties. E.g., Sonalika and Kafyan Sona were selected after introduction of Mexican varieties. (b) Direct multiplication and released as new varieties: The very useful and high yield dwarf varieties of rice (e.g., TN-1, IR-8) and wheat (e.g., Sonora 64, Lerma Rojo) are introduced in India. There are many more examples of direct release of varieties in other crop plants like soya- bean, oat, tomato, onion, cauliflower etc. (c) Introduced varieties as donor in hybridization programme: Sometimes the introduced varieties have better-quality in comparison to the already existing varieties. This may be used as donor for disease, pest and stress resistance for plant type and quality characters in hybridization. In case of rice, the dwarfing gene from TN-1 or IR-8 have been used for developing, other dwarf rice varieties in rice. All the sugarcane varieties have been derived from introduced noble cane variety of Saccharum officinarum. (d) Mutation breeding: Sometime, if the introduced variety is lacking a few characters but is agronomically superior may be treated with mutagen to resolve the deficiency or incompetency. For example, a wheat variety Sonora-64 introduced with red colour grains did not take too much UTTARAKHAND OPEN UNIVERSITY Page 14 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 attention of the farmers; therefore, the new mutagenic variety produced called Sharbati Sonora with amber colour grains by the Gamma- ray treatment by M.S. Swaminathan. 1.4 AGRICULTURAL ORIGINS Evidence for plant cultivation and domestication comes from a variety of sources including:  Carbonized remains formed by high temperature ‗baking‘ under low oxygen.  Parched plant remains produced under extreme dry conditions.  Impregnations of metal oxides.  Fecal remains.  Mineralization where cell cavities are replaced by minerals such as silica (phytoliths).  Impressions pressed into pottery and bricks.  Plant material sunk in peat bogs or mud under anaerobic conditions. In these deposits, domestication is considered to be signified by substantial increases in the size of seeds, dramatic reductions in seed or fruit coat thickness and the apparent loss of dispersal organs. These confirmations are often complemented by the human artifacts which offer traces about diet, such as grinding wheels and sickles. Soil from prehistoric settlements is sometimes passed through screens to obtain small objects, but this technique often allows valuable material such as seeds to be lost. The transformation of human from hunter to farmer is a gradual process which took thousands of years. The early documentation of this has been recorded in the excavations in the Tehuacán Valley of Mexico where excavates 12 sites and uncovered 12,000 years of agricultural history in the area. Primarily, humans who got their food from small animals and wild plants now collect plant products in a set round of annual activities. About 9000 years ago, it became more difficult and humans began to relocate more of their energy to collections of wild plant like avocados, chili, peppers squash etc. They dispersed into small forage groups during the unfavorable seasons while came together during the abundant season. They tried to begin the produced wild plants through the periodic farming, however, the effort was negligible. Over the next 5000 years, the humans of the Tehuacán Valley slowly enhanced the utilization of the cultivated vegetation, such that, by 7000 BP, about 10% of their diet came from cultivated plants. They were outside the native areas of domestication, but by this time a large group of potentially introduced crops were growing, including maize, amaranth, beans, squash, and peppers. As the time precede, humans continued to put more and more effort in cultivation. Around 3000 BP, a large proportion of their diet came from cultivated sources. They also cultivated the cotton plants. In animal kingdom the records indicated that the dog has domesticated about 5000 years ago and Turkeys about 2000 years ago. Parallel verification of evolutions from hunters to farmers can be established at copious places across the Near East. One such site is Jericho in the Jordan Valley, where a continuous record of 9000 years of habitation was left as people built new mud huts on top of others as they deteriorated over time. In the earliest period, the settlement consisted of Natufians, who were primarily hunters of gazelles and foxes and who UTTARAKHAND OPEN UNIVERSITY Page 15 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 tended a few cereals but had no domestic animals. About 9000 years ago, they began to raise cereals in earnest, and there is the first confirmation that sheep and goats were being domesticated. A similar long-term record of successive settlement is recorded at Catalhöyük, Turkey, where people were initially foragers who raised a few cereals on the side, but by 10,000 BP had domesticated cattle and were large-scale farmers. Agriculture arose about 12,000 years ago separately at many locations across the world. Vavilov (1926, 1949–1950) initially recognized 8 centres of domestication, mainly based upon the outlines of crop diversity. These were customized by Harlan in 1967 that are based on the native range of crop progenitors along with the combination of many archaeological confirmations. Harlan identified 3 comparatively small geographical areas, which are called centres, and another three rather diffuse regions, which are called noncentres (Fig 1.1). According to him these centres were most likely self-governing but the non-centres may have had few contacts with neighboring ones. The three centres were the: (i) Near East (parts of Jordan, Turkey, Syria, Iraq and Iran), (ii) Mesoamerica (Central America & Mexico) and (iii) North China. He considered Africa, South-East Asia and South America to be non-centres. Recently, eastern North America has also been added as a centre of crop origin. Fig. 1.1: Earliest places where agriculture began; A1- Near East centre; A2- African non-centre; B1- North Chinese centre; B2- South East Asian and south Pacific non-centre; C1-Mesoamerican centre; C2-South American non- centre; D-Eastern North American centre (Figure modified from Harlan, 1967) The sufficient evidences have specified that human started farming in the hills above the Tigris river on the western edge (now Iran). A lot of primeval agricultural places have been positioned in this region. Among the first crops domesticated in this region were einkorn and emmer wheat, pea, lentil chickpea, barley and flax. Sheep and goats were the first domesticants animal. UTTARAKHAND OPEN UNIVERSITY Page 16 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 Agriculture began at the early age in the forest margins of Ethiopia, West Africa, and along a transcontinental band through the savannah as well. Ethiopia has provided the most primitive confirmation (6th millennium BP) of African farming but the other origins are most likely just as old. People in the Sahel domesticated pearl millet, sorghum, guinea-fowl and African rice. West Africans were cultivated cowpea, African yams, and the oil-palm. Ethiopians domesticated finger millet, coffee and teff. Data on China and Asia are still rising, but they were evidently primitive regions of animal and plant domestication. The Wei and Yellow river basins in the north China and the Yangtze valley in the south China also illustrate proof of agriculture about 8000 BP. They started domestication of plants like rice millets; soybean etc and pigs as animal were the early Chinese domesticants. South-East Asia is the biggest dilemma due to its humid and hot weather surroundings lead to rapid degradation of food resources, however, there is evidence that farming was practiced by 8000 to 10,000 BP in New Guinea and Thailand. Sugar cane and banana were first domesticated in South-East Asia. Louis Pierre de Candolle, a Swiss botanist, worked on phytogeography and published his work in 1883 entitled ―Origin of cultivated plants‖ which sustains the available prehistoric literatures and ancient ethnological studies. His work documented the history of 247 species of cultivate plants and consists the ancestral forms of regions of domestication. According to de Candolle, cultivated plants have originated for a while in the distant past from wild ancestors in relatively restricted areas of the world. Further, he also recommended that each crop had a single region of origin. Based on his work, he recognized following classes of economic plants: Classes Cultivated plants Class 1: Pyrus malus, Solanum melongenum, Setaria italic, Old world plants that have been Panicum miliaceum, Pennisetum typhoideum, Oryza cultivated for over 4,000 years sativa, Sorghum vulgare, Triticum vulgare etc. Class 2: Beta vulgaris, Avena sativa, Papaver somniferum Old world plants that have been Secale cereal, Saccharum officinarum, Juglans cultivated for over 2,000 years regia etc. Class 3: Fagopyrum esculentum, Coffea arabica, Old world plants that have been Abelmoschus esculentus, Petroselinum crispum, cultivated for less than 2,000 years Pastinaca sativa etc. Class 4: New world plants that have been Theobroma cacao, Phaseolus vulgaris, Zea mays cultivated for more than 2,000 years Ipomea batatas, Nicotiana tabacum etc. Class 5: Persea americana, Gossypium sp., Psidium guajava New world plants that have been Ananas comosus, Solanum tuberosum, Vanilla cultivated before the time of Columbus planifolia etc. Class 6: Rubus biflorus, Cinchona sp., Prunus domestica, UTTARAKHAND OPEN UNIVERSITY Page 17 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 New world plants that have been Hevea brasiliensis, Fragaria vesca etc. cultivated since the time of Columbus Agricultural probably began independently in the New World, 1000–2000 years later than in the Old World. There was a comparatively dense Mesoamerican centre expanding from Honduras to Mexico City, while South American produce emerged in a wide region covering most of coastal and central South America. Coastal Peru is often called as a central point of early South American agriculture, but the data are somewhat prejudiced, since the majority archaeological research has been achieved on dry coastal regions where plant material is readily preserved. Three ecological/geographical regions of domestication have been proposed: (i) An Andean high elevation complex (ii) A lowland complex (iii) An Andean mid-elevation complex The centre in eastern North America spanned the area between the Appalachian Mountains and the western borders of Missouri and Arkansas. A diverse group of crops and animals were initially cultivated and domesticated in the America. Potatoes, quinoa and several other tuber crops were domesticated in the Andean high-elevation complex. Groundnut, amaranth, bean, coca, etc were part of the Andean mid-elevation complex. Avocados, chilli, cotton, peppers, manioc, pawpaw, squash, pineapple, sweet potato and yams were domesticated in the tropical lowlands of Central and South America. In recent times, fruit phytoliths (silica deposits) have been recovered from domesticated Cucurbita in early Holocene archaeological sites in south- western Ecuador (12,000–10,000 BP). The starch grains of yam, manioc and arrowroot have been found on ancient plant milling stones from the Panamanian tropical forest (7000–5000 BP), supporting the independent emergence of plant domestication in the lowland neotropical forest. Species of avocado, amaranth, beans, cotton, chenopod, chilli peppers, pumpkin and squash were domesticated independently in Mesoamerica, along with maize. Turkeys were the first animals domesticated in Mexico, while llamas and guinea pigs were the first animals tamed in South America. Sunflower, goosefoot, sump weed and squash originated in North Americans. 1.5 ORIGIN OF CULTIVATED PLANTS-VAVILOV’S CENTRES OF ORIGIN Agriculture is the oldest occupation of the human‘s oldest occupation and probably began when they discovered that certain seeds when spilled on disturbed ground grew in some mysterious way into new plants. It now appears certain that early domestications were made more or less alongside and independently on the lower slopes of the Zagros Mountains, the ‗fertile crescent‘ of the Tigris and Eupharates valleys in northern Iraq (Old World), and in the Tehuacán Valley of Mexico (New World). Ancient arrangement was astonishingly copious in both these regions. The initial confirmation of authentically cultivated forms so far discovered, dates from about 7000 UTTARAKHAND OPEN UNIVERSITY Page 18 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 BC in both the hemispheres. Every necessary plant species which we worth nowadays is a living compliment to our primitive ancestors who, discovered the virtues of certain plants, long before the dawn of recorded history, chosen the most valuable wild species and intensely altered them. Many of them have been changed so much that their wild ancestors cannot be traced with conviction. Indeed, early humans were a plant breeder, devoid of any sufficient acquaintance of genetics, and exhibited a notable knowledge in domesticating plants and preparing them for food. For the invention of numerous of those economic plants, their relocations from one continent to another and information of their properties and cultivation, we are indebted to the scholars of antiquity, the ancient conquerors, the medieval trade princes, the Spanish conquistadores and the mariners and explorers of many lands. They all took with them the seeds of their native plants and in revisit, brought home for transplantation anything they found fit. Even though human domesticated plants at very first but he did not document them critically for a long time however some irregular plant sketches were made by the Palaeolithic man. The actual establishment of the systematic study of plants, however, was laid by the Greek and Roman physician-botanists such as Theophrastus (often known as ‗the father of botany‘), Dioscorides, Pliny the Elder, Galen and others Dioscorides‘ De Materia Medica is perhaps one of the most important ancient writings. For the subsequently 14 centuries, in botany as in other sciences, roughly nothing was proficient. The previous attempts of Aristotle and Theophrastus were considered thus accomplished and reliable that there was little besides to study and surely not anything for questioning. However, the revival of information in the ‗Renaissance‘ had a enormous impact on agriculture. One of the old perspectives regarding the origin of cultivated plants postulated that these are the gift to humans by the God. In addition, there was a faith that the procedure of cultivation itself enhanced the genetics of plants. However, men perplexed these submissions by the end of the 18 century. Alexander von Humboldt in 1807 proclaimed that ‗we know nothing of the original source of our most useful plants; their origin is an impenetrable secret‘. These domesticated plants were arise by the intense modifications in the wild plants which were under cultivation. Mendel‘s work, first published in 1865, remained obscure until 1900. He formulated the laws of inheritance and attributed the origin of cultivated plants to natural selection and hybridisation. Nikolai Ivanovich Vavilov A Russian scientist, Nikolai Ivanovich Vavilov was a pioneer worker in the field of plant introduction and exploration. He was recognized for the gene centre concept of cultivated plants and their wild progenitors. Under his novel guidance, one of the greatest investigators in crop geography and genetics, widespread collections of these plants and their wild relatives were made by sending expeditions all over the world. His deductions were foundation on a selection of facts, obtained from the sources diverse from those of his predecessors, such as morphology, cytology, genetics anatomy distribution and reaction to disease. Vavilov maintain the record of UTTARAKHAND OPEN UNIVERSITY Page 19 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 the varied forms of the most significant cultivated plants and their allocation over a range of parts of the earth. He perceived that the allocation of plants was not uniformly distributed. In few limited areas, an extensive range of genetic inconsistency was encountered. For example, South America for potato and Ethiopia for wheat. Over fifty per cent of the diversity found in the world was present in these regions. There are a few such regions and mostly they are small areas restricted to the mountains or foothills of the subtropics and tropics. Vavilov called these regions with the greatest wealth of forms, ‗gene or diversity centres‘ and further suggested that these are the regions of origin as well as dispersion. From these centres, the species have migrated in different directions in the course of which many recessive mutants arose. All discrepancy from the cultivated type to a entirely wild species were to be seen in these centres. In the case of potato, a investigate for its prime centre of origin, the Andes of South America, exposed all degrees of variation from a tuber forming cultivated type to the wild non-tuber forming types. These centres were characterized by the presence of dominant genes. It emerged that the heart of these gene centres was distinguish by the preponderance of the dominant genes and towards the peripheral regions these genes were replaced by recessive alleles increasingly. A Vavilov Center (of Diversity) is a region of the world first specify by Nikolai Vavilov to be an original center for the domestication of plants. For crop plants, Nikolai Vavilov identified various numbers of centers. It was only 3 in 1924 which increased by 8 in 1935 and reduced to seven again in 1940. Vavilov's scheme as updated by Schery and Janick Vavilov centers are those centers which maintain the high diversity of crop and their wild relatives can be found which are representing the natural relatives of domesticated crop plants. Later in 1935 Vavilov divided the centers into 12, giving the following list: 1. Chinese center 2. Indian center (a) The main centre Assam and Burma (now called Myanmar) (b) The Indo-Malayan centre includes Indochina and the Malay Archipelago 3. Indo-Malayan center 4. Central Asiatic center 5. Persian center 6. Mediterranean center 7. Abyssinian center 8. South American center (a) The Peruvian-Ecuadorean-Bolivian centre (b) The Chiloe centre (c) The Brazilian-Paraguayan centre 9. Central American center 10. Chilean center 11. Brazilian-Paraguayan center UTTARAKHAND OPEN UNIVERSITY Page 20 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 12. North American center Table 1.2: Cultivated plants of eight world centers of origin (Source: Schery 1951 and Janick 2002) Center Plants (1)  Grains and Legumes: maize, common bean, lima bean, tepary South Mexican and bean, jack bean, grain amaranth Central American Center:  Melon Plants: malabar gourd, winter pumpkin, chayote Southern sections  Fiber Plants: upland cotton, bourbon cotton, henequen (sisal) of Mexico, Guatemala, H onduras and Costa Rica.  Miscellaneous: sweet potato, pepper, papaya, guava, cashew, chochenial, arrowroot, wild black cherry, cherry tomato, cacao. 2) Peruvian, Ecuadorean, Bolivian Center:  Root Tubers: Andean potato, Other endemic cultivated potato species. Fourteen or more species with chromosome numbers varying from 24 to 60, Edible nasturtium  Grains and Legumes: starchy maize, lima bean, common bean  Root Tubers: edible canna, potato (2)  Vegetable Crops: pepino, tomato, ground, pumpkin, pepper, South American Center cherry includes 62 plants listed; three subcenters  Fiber Plants: Egyptian cotton  Fruit and Miscellaneous: cocoa, passion flower, guava, tobacco, coca, heilborn, quinine tree, cherimoya, 2A) Chiloé Center (Archipelago near the coast of southern Chile) Common potato (48 chromosomes), Chilean strawberry 2B) Brazilian-Paraguayan Center manioc, peanut, rubber tree, pineapple, Brazil nut, cashew, Erva- mate, purple granadilla.  Cereals and Legumes: durum wheat, emmer, Polish wheat, spelt, (3) Mediterranean oats, sand oats, canarygrass, grass pea, pea, lupine Mediterranean Center:  Forage Plants: Egyptian clover, serradella, white clover, crimson Includes all of Southern clover Europe and Northern  Oil and Fiber Plants: flax, rape, black mustard, olive Africa bordering the Mediterranean Sea.  Vegetables: cabbage, turnip, lettuce, asparagus, celery, chicory, pa Listed 84 plants rsnip, rhubarb, garden beet  Ethereal Oil and Spice plants: caraway, anise, peppermint, sage, hop thyme (4)  Grains and Legumes: einkorn wheat, durum wheat, poulard Middle East: wheat, common wheat, oriental wheat, Persian wheat, two- Includes interior of Asia row barley, rye, Mediterranean oats, common oats, lentil, lupine Minor, all  Forage Plants: alfalfa, Persian clover, fenugreek, vetch, hairy of Transcaucasia, Iran, vetch UTTARAKHAND OPEN UNIVERSITY Page 21 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 and the highlands  Fruits: fig, pomegranate, apple, pear, quince, cherry, hawthorn. of Turkmenistan. Listed 83 species (5) Abyssinian Center:  Grains and Legumes: Abyssinian hard wheat, poulard Includes Ethiopia, Eritre, wheat, emmer, Polish wheat, barley, grain sorghum, pearl and part of Somalia. 38 millet, African millet, cowpea, flax, teff species listed; rich in  Miscellaneous: sesame, castor, bean, garden, okra, myrrh, coffee, wheat and barley. indigo cress, enset. (6) Central Asiatic Center: Includes Northwest India  Grains and Legumes: common wheat, club wheat, shot, peas, (Punjab, Northwest lentil wheat, horsebean, chickpea, mung, mustard bean, Frontier Provinces and flax, sesame Kashmir), Afghanistan, T  Fiber Plants: hemp, cotton adjikistan, Uzbekistan,  Vegetables: onion, garlic, spinach, carrot and western Tian-Shan.  Fruits: pistachio, pear, almond, grape, apple. 43 plants Two sub-centers: Indo-Burma: Main Center (India): Includes Assam, Bangladesh and Burma, but not Northwest India, Punjab, nor Northwest Frontier Provinces, reported 117 plants  Cereals and Legumes: chickpea, pigeon pea, urd bean, mung bean, rice bean, cowpea,  Vegetables and Tubers: eggplant, cucumber, radish, taro, yam  Fruits: mango, tangerine, citron, tamarind  Sugar, Oil, and Fibre Plants: sugar cane, cotton, coconut, (7) palm, sesame, safflower, tree, oriental Indian Center cotton, jute, crotalaria, kenaf  Spices, Stimulants, Dyes, and Miscellaneous: indigo, hemp, black pepper, gum, sandal wood, cinnamon tree, croton, bamboo, turmeric, 7A) Siam-Malaya-Java: statt Indo-Malayan Center: Includes Indo- China and the Malay Archipelago, 55 plants  Cereals and Legumes: Job's tears, velvet bean  Fruits: pummelo, banana, breadfruit, mangosteen  Oil, Sugar, Spice, and Fibre Plants: candlenut, coconut palm, sugarcane, clove, nutmeg, black pepper, manila hemp. (8)  Cereals and Legumes: rice, broomcorn millet, Italian Chinese Center: millet, Japanese barnyard millet, sorghum, buckwheat, hull-less A total of 136 endemic barley, soybean, Adzuki bean, velvet bean UTTARAKHAND OPEN UNIVERSITY Page 22 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 plants are listed in the  Roots, Tubers, and Vegetables: Chinese yam, radish, Chinese largest independent cabbage, onion, cucumber center  Fruits and Nuts: pear, litchi, orange, peach, cherry, Chinese apple, apricot, , walnut, ,  Sugar, Drug, and Fibre Plants: sugar cane, opium poppy, ginseng camphor, hemp. These areas of diversity constitute only a small proportion (two to three per cent) of the total land surface of the earth and are geographically distinct, being isolated by deserts or mountain ranges. Eighty-five per cent of the 640 species listed by Vavilov originated in the Old World (Asia, Europe and Africa), and the remainder are of the New World (the Americans). All the centres of diversity are situated in the mountainous regions of the tropical zones of the Old and New Worlds. The wide temperature fluctuations and the strong ultraviolet radiations in these areas are the grounds of the origin of such a multitude of forms. The extraordinary diversity of the climate of all mountains, especially the tropical ones, makes it easier for the newly originated mutants to find a suitable environment than it would be in a region with a more uniform climate. Vavilov further distinguished between primary and secondary or ‗accumulation‘ gene centres. He suggested that the process of domestication from the native wild relatives began in the primary gene centre, and these are characterised by the dominant genes. As the cultivated plants later migrated to another gene centre, they were subjected to the same natural force that again led to a considerable increase in the diversity of the cultivated plants that came into this region. In this way, a new or secondary gene centre was developed from the cultivated plants in question. This gene centre was significantly characterised by a diversity of recessive characters and was also devoid of wild relatives. The Abyssinian centre was extraordinarily rich in the varieties of wheat, barley, pea, flax and lentil, but there are none of the wild relatives that are found in the Middle East, many thousands of kilometers from Ethiopia. Thus, in the primary gene centre the diversity was a consequence of ancient cultivation. The longer a given biological entity occupied a particular region, the larger would be the number of variables it would exhibit (Willis‘ age-and area hypothesis, 1922). In contrast, the reasons for the diversity in the secondary gene centre were ecological diversity, farming practice, human migration patterns (attraction of different tribes to different races of a crop) and the internal biological dynamics of hybridisation, segregation and selection. Even within a basic centre of biodiversity, there are very tiny areas of varietal richness, which Vavilov called as ‗agro-ecological groups‘. This idea was expected by Harlan was used the term ‗microcentre‘- a region that may contain an astonishing variation of one or more crops. According to Vavilov, many of our most important cultivated plants had a multiple rather than a single origin as suggested by de Candolle. These primary crops were domesticated directly from the wild plants, example of which are wheat, barley, rice, soybean, flax, cotton, maize and UTTARAKHAND OPEN UNIVERSITY Page 23 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 potato. Vavilov pointed out that there were at least two distinct centres of distribution for wheat; soft wheat originated in the Southeast Asia, whereas the hard wheat came from the Mediterranean region. Likewise, barley was domesticated in the Southwest Asia, North Africa and Southeast Asia. On the other hand, secondary crops, such as rye, oats, etc. originated as weeds growing with the primary crops. As the primary crops were taken to areas with harsher climatic conditions and poorer soils, the percentage of weeds increased since they were better adapted to such conditions. Hence, finally the weeds became the crop, and the crop became the weed. 1.6 SUMMARY The broad objective of the present unit is to know about the domestication and introduction of plant species and their origin. The history of human evolution is very old where the prehistoric human primarily got their food from the wild edible plants but as the time passed, they started to cultivate the wild plants. Therefore, the traditions of those prehistoric humans take very prominent part in the origin of cultivation of plants. It is believed that most of the plant were cultivated first during historical times. However the paleontological data is entirely unavailable for cultivated plants and archaeological information is fragmented and very poor. The efforts of some ancient Roman and Greek naturalists like Theophrastus, Elder, and Galen Pliny laid down systematic groundwork of wild plant domestication. Alexander von Humboldt also considered the origin of useful plants is a big secret as well. Finally, Darwin‘s evolutionary theory recommended that origin of cultivated plants take place through natural selection and repetitive hybridization. If we talk about the agriculture it is believed that agriculture have been originated somewhere in the well irrigated highlands of the Indus, Euphrates and Nile and Tigris rivers nearly 7000-13000 years ago. A few places of other prehistoric sites like Tehuacan valley in modern Mexico and banks of Yellow river in modern China are also the evidence of ancient agricultural activities. Do you ever think that how a regional cultivated crop becomes cosmopolitan in their distribution? It could become possible only due to the ―plant introduction‖ and domestication of a particular region to the other region. The plant introduction is a progression of introducing plants (a genotype or a group of genotypes) from their own environment to a new environment. This process may include new varieties of crop or the wild relatives of crop species or totally a new crop species for the area. Introduction may be classified into two categories: (i). Primary introduction: When the introduced variety is well suitable to new environment afterward it released devoid of any modification of genotype for commercial production. (ii). Secondary introduction: When the introduced variety is subjected to the selection or used in hybridization UTTARAKHAND OPEN UNIVERSITY Page 24 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 programme with local varieties having some new characters to obtain the superior varieties called secondary introduction. The plant domestication is a method of bringing of wild plants under cultivation by making them appropriately modified for new environment. Domestication is the reflection of co-evolution where both the components (plants and humans) developing a symbiotic relationship because human and plant behaviours evolve to suit one another. Some main purposes of plant domestication are germplasm conservation, enhancement in agriculture, forestry and industry, aesthetic interest etc. The major agencies which are associated to plant Introduction in India are National Bureau of Plant Genetic Resources (NBPGR), Forest Research Institute (FRI), Botanical Survey of India (BSI) etc. Agriculture is the oldest occupation of the human‘s oldest occupation. A Russian scientist, Nikolai Ivanovich Vavilov was a pioneer worker in the field of plant introduction and exploration. Vavilov proposed some centers of origin of cultivated plant which are known as Vavilov‘s centers of origin. These are those centers which maintain the high diversity of crop and their wild relatives. According to Vavilov, many of our most important cultivated plants had a multiple rather than a single origin as suggested by de Candolle. These primary crops were domesticated directly from the wild plants, for example wheat, barley, rice, soybean, flax, cotton, maize, potato etc. 1.7 GLOSSARY Prehistoric time: the vast period of time before written records or human documentation, includes the Neolithic Revolution, Neanderthals and Denisovans, Stonehenge, the Ice Age and more. Wild relative crop: wild plant species that are genetically related to cultivated crops. Domestication: the process of taming an animal or plant and keeping it as a pet or on a farm or cultivation. Evolution: the development of plants, animals, etc. over many thousands of years from simple early forms to more advanced ones Co-evolution: the influence of closely associated species on each other in their evolution. Symbiosis: It is a type of a close and long-term biological interaction between two different biological organisms. Archaeology or archeology: It is the study of human activity through the recovery and analysis of material culture. Plant Hybridization: It is the process of crossing two genetically different individuals to result in a third individual with a different, often preferred, set of traits. Cultivation: It is called deliberately growing a plant. Plant introduction: It is a progression of introducing plants (a genotype or a group of genotypes) from their own environment to a new environment. UTTARAKHAND OPEN UNIVERSITY Page 25 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 Acclimatization: It is the capability of a plant variety to become adapted to a new edaphic and climatic condition. Breeding systems: It referring in plants is simple called as "Who mates with whom" Pure breed: Breeding between pure breed where the ancestors on both mating type have been members of a recognized breed. Cross breed: Breeding where status of only one parent is known or breeding between two different breeds, varieties, or populations. Genetic variation or diversity: It is called as the diversity exists within different genotypes of the same species. Crop duration: The time duration from establishment to harvesting a crop is known as duration of the crop. Germplasm: It is living tissue from which new plants can be grown. It can be a seed or another plant part – a leaf, a piece of stem, pollen or even just a few cells etc. Conservation: It is the moral philosophy and conservation movement focused on protecting species from extinction, maintaining and restoring habitats, enhancing ecosystem services, and protecting biological diversity. Aesthetic value: It is the emotional or spiritual value attributed to a work of art or nature because of its beauty or other factors associated with aesthetic preference. Plant variety: It represents a more precisely defined group of plants, selected from within a species, with a common set of characteristics. Propagules: a vegetative structure that can become detached from a plant and give rise to a new plant, e.g. a bud, sucker, or spore. Plant quarantine: It is a technique for ensuring disease- and pest-free plants, whereby a plant is isolated while tests are performed to detect the presence of a problem. Phytogeography or botanical geography: It is the branch of biogeography that is concerned with the geographic distribution of plant species and their influence on the earth's surface. Vavilov center: A center of origin is a geographical area where a group of organisms, either domesticated or wild, first. Biodiversity: developed its distinctive properties. They are also considered centers of diversity. Biodiversity is the biological variety and variability of life on Earth. Biodiversity is a measure of variation at the genetic, species, and ecosystem level. 1.8 SELF ASSESSMENT QUESTIONS 1.8.1 Multiple Choice Questions: 1. Centres of early civilization were in: (a) Tropical plains (b) River valleys (c) Temperate plains (d) Hills 2. The earliest place where agriculture and civilisation are believed to have started UTTARAKHAND OPEN UNIVERSITY Page 26 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 (a) Nile (b) Northern plains of India (c) China River valley (d) All of the above 3. Ethiopia is the original home of (a) Coffee (b) Maize (c) Rice (d) Cabbage 4. Cabbage originated in: (a) Mexico and Central America (b) Peruvian Andes (c) Mediterranean (d) South West Asia 5. Maize evolved in (a) Brazil (b) Mexico and Central America (c) U.S.A. (d) Asia Minor and Afghanistan 6. The centre of origin of Almond and Apple is (a) South-West Asia (b) South-East Asia (c) China (d) Asia Minor and Afghanistan 7. The original home of Rice is (a) South-West Asia (b) South-East Asia (c) Mediterranean (d) China 8. Peruvian Andes are believed to be centre of origin of (a) Tomato (b) Potato (c) Tomato and Potato (d) Tomato, Potato and Chillies 9. The origin of Sunflower is believed to be in (a) Mexico and Brazil (b) Brazil (c) U.S.A. (d) Peruvian Andes 10. South-East Asia is thought to be centre for the origin of (a) Rice (b) Rice and Sugarcane (c) Rice, Sugarcane and Mango (d) Rice, Sugarcane, Mango and Banana 1.8.2 Fill in the blanks: 1. The famous cultivated plant which developed in China is _______ 2. The birthplace of Hevea/Para Rubber is _______ 3. The centre of origin of Wheat is _______ 4. Gene banks comprise _______ UTTARAKHAND OPEN UNIVERSITY Page 27 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 5. Dwarf wheats were developed by the scientist _______ 6. The dwarf varieties brought from Mexico into India were _______and _______ 7. IR.-36 was developed through breeding of _______ and _______ 8. Cereals belong to family _______ 9. Major crops of the world belong to family _______ 10. Triticale is a man-made cereal which has been developed through hybridisation between _______ and _______ 1.8.3 True and False: 1. Rice is the principal cereal of Tropical region. 2. The plants introduced from Old World to New World is maize. 3. Food grains which provide the most important staple food to man are Legumes. 4. Rice is the good source of carbohydrate. 5. Cereals are biennials crop. 6. Botanical name of Rice is Pennisetum typhoides. 7. Sharbati Sonora and Sonalika are the Improved Wheat varieties. 8. Paddy is Rice grain with husk. 9. Polished rice is the best form of rice. 10. Triticum monococcum is the common bread wheat. Answer Key: 1.8.1: 1(c); 2(d); 3(a); 4(c); 5(b); 6(d); 7(b); 8(d); 9(c); 10(d). 1.8.2: 1. Tea; 2. Brazil; 3. South-West Asia; 4. Seed banks, orchards, tissue culture and cryopreservation; 5. Borlaug; 6. Sonora-64, Lerma Rojo-64; 7. Thirteen Rice varieties, Oryza nivara; 8. Gramineae; 9. Gramineae; 10. Wheat, Rye 1.8.3: 1. True; 2. False; 3. False; 4. True; 5. False; 6. False; 7. True; 8. True; 9. False; 10. False 1.9 REFERENCES  https://www.studyandscore.com/studymaterial-detail/Alphonse-de-Candolle-Origin-of- cultivate-plants-Classes-of-economic-plants-Regions-of-first-origin  https://www.studyandscore.com/studymaterial-detail/origin-and-introduction-of-plants- domestication-of-plants-basis-of-plant-domestication  Janick J (2002) History of Horticulture, Purdue University,  Schery R. W. Adapted from Vavilov (1951) by, Plants for Man, Prentice Hall, Englewood Cliffs, NJ, 1972 1.10 SUGGESTED READINGS UTTARAKHAND OPEN UNIVERSITY Page 28 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603  Janick J (2002) History of Horticulture, Purdue University,  Schery R. W. Adapted from Vavilov (1951) by, Plants for Man, Prentice Hall, Englewood Cliffs, NJ, 1972 1.11 TERMINAL QUESTIONS 1.11.1 Short answer type questions: 1. What do you under by introduction of plant species? 2. Describe the primary and secondary introduction in brief. 3. What do you know about the domestication of plant? 4. What is acclimatization of a species? 5. Highlight the main purposes of plant introduction and domestication. 1.11.2 Long answer type questions: 1. Write in detail note on procedure and agencies associate of plant introduction in India. 2. Discuss the merits and demerits of plant introduction. 3. Highlight some achievements of plant introduction in detail. 4. Discuss the origin of agriculture in detail. 5. What do you understand by the Vavilov‘s centres of origin? UTTARAKHAND OPEN UNIVERSITY Page 29 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 UNIT-2 FOOD SPECIES, FRUITS AND NUTS Contents 2.1- Objectives 2.2- Introduction 2.3- Food species 2.3.1- Cereals 2.3.2- Pulses 2.3.3- Millets 2.3.4- Vegetables 2.4-Fruits 2.5-Nuts 2.6-Summary 2.7-Glossary 2.8-References 2.8-Suggested readings 2.10-Self Assessment Questions 2.11-Terminal Questions UTTARAKHAND OPEN UNIVERSITY Page 30 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 2.1 OBJECTIVES After reading this unit the students will be able to known about the;  Major food species of the world.  Origin, cultivation, food value and production of the cereals.  Origin, cultivation, food value and production of the pulses.  Food value and uses of millets.  Major vegetable, fruit and nut species and its nutrient values and uses. 2.2 INTRODUCTION Food plant species may be defined as those plant species or plant organs that can be included in human meal or a part of it. Human meals can be chiefly divided into three categories breakfast, lunch and dinner. These three meals are mainly consists either of plant products (cereals, vegetables, legumes, fruits and nuts) or products of animals (meat, cheese, butter, curd, yoghurt, milk, eggs etc.). As the title of the block ―Plant resources of food value‖ asks to mention about the plant species which can be used as food, so here in this unit we are going to study only about the plant products which make our meals. As we look at the major classification of plant products used as food it appears that only higher plants made their way to our dining table but this is not the complete truth. Human also use various lower plants in their diet. Among these lower plants macro-fungi such as mushrooms, morels, truffles and puffballs contribute the major portion; Algae such as sea grapes (Caulerpa lentillifera), Nori or purple laver (Porphyra spp.), Aonori or green laver (Monostroma spp. and Enteromorpha spp.), Kombu or haidai (Laminaria japonica), Wakame, quandai-cai (Undaria pinnatifida), Hiziki (Hizikia fusiforme), Mozuku (Cladosiphon okamuranus), Dulse (Palmaria palmata), Irish moss or carrageenan moss (Chondrus crispus), Winged kelp (Alaria esculenta), Ogo, ogonori or sea moss (Gracilaria spp.), Callophyllis variegata, Spirulina, Chlorella, Gelidium corneum, Gracilaria lichenoides and Eucheuma spinosum are the second largest contributor, and only a single species i.e. Matteuccia struthiopteris of Ferns made to the contributor list. Some species of lichens contribute in making spices. Very few species of Gymnosperms provide some nuts to eat such as the Mexican pinon (Pinus cembroides), the Colorado pinion (P. edulis), the Italian stone pine (P. pinea), and the Chinese nut pine (P. koraiensis), Chilgoza Pine (Pinus girardianana) and Sago from some cycads e.g. Cycas revoluta. UTTARAKHAND OPEN UNIVERSITY Page 31 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 Angiosperms are the most dominating plant group in obtaining food products. The main reason why these plants are so much in demand as food products because these species contain all the necessary and sufficient nutrients like carbohydrates, fats, proteins, vitamins and minerals. A major portion of the global supply of food products is obtained from rice, wheat, maize, sugar cane, potato and beans etc. Some beans and vegetables such as mustard, groundnut, soyabean, sunflower, linseed, olive and castor oil are widely used in the food industry. Almost all the vegetables provide vitamins and mineral salts that are essential for human health. The lack of these vegetables from the diet results in vitamin deficiency and consequently causes some diseases such as beriberi, scurvy and pellagra from the lack of vitamin B (thiamine), vitamin C and vitamin B6 (niacin), respectively. As we saw in the above paragraphs, with the help of some examples, plants constitute a large proportion of human diet. A huge section of all the edible plant species can be categorized into three broad categories such as cereals, vegetables and legumes. We will study these three categories in details further in this chapter. 2.3 FOOD SPECIES 2.3.1 Cereals The term ‗cereals‘ is derived from a Greek festival ‗Cerealia‘ which is celebrated in ancient Rome to honor the goddess Ceres who is the goddess of agriculture, grain crops, fertility, and motherly relationships. In this festival Romans used to offer grains such as wheat and barley to the goddess Ceres. Cereals are the important component of human diet. True cereals belong to the family Poaceae also known as grass family (Fig 3.1). On the other hand there are some other crops which are used to make flour but these species do not belong to the family Poaceae. These plants are called as pseudocereals for example buckwheat (Fagopyrum esculentum), quinoa (Chenopodium quinoa), Amaranthus spp. etc. Cereals have a significant role in the evolution of Human civilizations. No civilization can ever be imagined without a stable supply of food and the agricultural revolution was the answer to the mentioned problem. Cereals were the first plants ever to be domesticated and cultivated in agricultural lands. Roughly every civilization, whether it is Ancient Egypt, Greece, Inca, Indus valley, Mayan, Mesopotamian and Roman was based on one or another species of the cereals. Now the question arises why the cereals have so much significance as food plant species. The cereals belong to the grass family and grasses have adapted themselves in growing almost on every possible habitat; cereals give very high yield per unit area; in comparison to the products UTTARAKHAND OPEN UNIVERSITY Page 32 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 of other plant species cereal grains are very compact and dry, this feature of cereals make them the perfect food species for handling, transporting and storing without the fear of spoilage; apart from all the above mentioned reasons the cereal grains have great nutritive value, as they contain a higher percentage of carbohydrates than any other food plant, sufficient protein (7-10 per cent), fats, vitamins and minerals. The general characteristics of cereals are following: Habit: Generally herbaceous annuals, few are perennial. Stem: Cylindrical, often erect, generally hollow (except at the nodes), have intercalary meristem. Primary, secondary and tertiary or even quaternary tillers may arise from the subterranean nodes of the primary, secondary and tertiary stems, respectively and this gives the plant a tufted appearance. Leaves: Alternate with parallel venation, having two distinct parts (leaf sheath and lamina). A ligule (membranous outgrowth) is also found at the junction of the leaf sheath and lamina. Inflorescence: Spike of spikelets (wheat, barley and rye) or panicle of spikelets (oats, rice and sorghum). Stamen: Usually three, sometimes six. Gynoecium: Single with two feathery stigmas. Flower: Chasmogamous and adapted for wind pollination. Fruit: One-seeded indehiscent fruit, or caryopsis, in which the pericarp is completely fused with the seed-coat. The most commonly used cereals are wheat, rice, corn, barley and oats. Some important millets are Finger millet (ragi), Foxtail millet, Barnyard millet and pearl millet. A study conducted in 2013 suggests that a large percentage of the world‘s population manages to survive chiefly on wheat, rice or maize (Graph 1). China (552,430,540 tones) is the world‘s largest producer of cereals, followed by United States (436,553,678 tones) and India (293,940,000 tones). Some most common species of cereals and millets are being described here in details. (A) Wheat Botanical Name: Triticum spp. Characteristic Features: Annual grass, comprising various wild (weeds) and cultivated species. Cultivated wheat (T. aestivum) grows to a height of 2-4 ft. Inflorescence terminal spike or head consisting of 15-20 spikelets borne on a zigzag axis. Individual spikelets sessile, solitary, consist of 1-5 flowers each. Mature grain consists of the embryo (6 per cent), a starchy endosperm (82 to 86 per cent), the nitrogenous aleurone layer (3 to 4 percent), and the husk or bran (8 to 9 per cent). Husk or bran is made up of the remains of the nucellus, the integuments of the seed coat, and the ovary walls or pericarp. Origin: On the basis of the number of chromosomes present in their reproductive cells, all the wheat species can be classified into three categories namely diploid, tetraploid and hexaploid wheat. Originally all the wheat varieties were considered to be diploid but in time, unknowingly, UTTARAKHAND OPEN UNIVERSITY Page 33 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 human provided them a chance to get naturally hybridized and after that their chromosomes doubled and gave rise to the modern day tetrapliod and hexaploid wheat varieties. Production: According to a datum published in 2012 wheat has a total production of about 670.8 million metric tons and it is the third most produced cereal after maize and rice. The top producer of wheat is China (120 million tons) followed by India (94.8 MT). India produces 86 per cent common bread wheat (T. aestivum), 13 per cent durum wheat (T. durum) and the remaining 01 per cent is emmer wheat (T. dicoccum). Types: On the basis of the growing season of wheat all the varieties of wheat can be categorized in to two main groups: Spring and winter wheat. Spring wheat: Short growing season (almost 100 days), no need of very low temperatures in the early phases of growth, sown in March-May, harvested in the late summer from August to September. Winter wheat: Long duration, require relatively low temperatures during the early phases of growth, sown in October-November and reaches maturity in the early summer of the next year, that is, May to July. On the basis of the chemical composition of the grain wheat can be divided into two broad groups: Soft and hard wheat. Soft wheat: Pale, possess a white starchy interior, lower in gluten content and make a weak flour suitable for making cakes, crackers, cookies, pastries and household flour. Hard wheat: Dark and vitreous show no white starchy area, higher in gluten content and make strong flour, a property desirable for bread making (leavened loaf). On the basis of official grain standards in the United States, wheat is categorized into seven grades: (1) hard-red spring, (2) durum, (3) hard-red winter, (4) soft-red winter, (5) white wheat, (6) red durum and (7) mixed wheat. Cultivation Method: The wheat seeds must be sown in about 4 to 5 cm inside the soil. Always put the seeds in rows and maintain a spacing of 20-22.5 cm between the rows. Planting or sowing the seeds in the right time is also important as delayed sowing can cause a gradual decline in the production. Season: Wheat is a Rabi crop that is grown in the winter season. Sowing of wheat takes place in October to December and harvesting is done during the months of February and May. The wheat crop needs cool winters and hot summers, which is why the fertile plains of the Indo-Gangetic region are the most conducive for growing it. Soil: Wheat grows best in a well-drained loamy soil. The term ―loam‖ is textural and reflects the particle size distribution of the soil and the relative quantities of the sand, silt and clay size fractions. Harvesting: The crop is harvested when it is ripe and the straw has turned golden yellow and brittle. At this stage, the moisture content of the grains is nearly 14 per cent. Wheat is sown in UTTARAKHAND OPEN UNIVERSITY Page 34 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 October and harvested in May-June. The crop remains dormant in the cold months of November to March and starts growing as the temperature rises in April. Uses: Wheat is the important source of carbohydrates to human. Wheat flour has good baking qualities and be used in various forms. In India almost 85-90 per cent of wheat is used to make roties. The soft wheat flour is mainly used in making cakes, biscuits, pastries etc. and hard wheat flour is used in bread making. Flour from Durum wheat is used in making macaroni, spaghetti, semolina, vermicelli, noodles. Wheat is also used in industrial preparations such as starch, gluten, distilled spirits, malt etc. Wheat starch is preferred by many laundries for use in finishing clothes. Gluten is used for the production of monosodium glutamate, a product that intensifies the flavour of food. Wheat bran is rich in proteins and vitamins and is a valued livestock feed. It is employed in the human diet not only for its nutritional quantities but for its role as ‗roughage‘, indigestible material, which stimulates intestinal peristalsis and adds bulk to the waste mass. Wheat straw is used as livestock feedstuff, animal bedding and compost. Some wheat straw is used for making corrugated paper, as well as high-quality insulated building board. (B) Rice Botanical Name: Oryza sativa Characteristic Features: The rice plant is a semiaquatic, free tillering annual grass with a cylindrical jointed stem (culm), about 50-150 cm tall. The internodes are shortest at the base, becoming progressively longer. Above each node, there is a pronounced thickening ‗pulvinus‘ with an intercalary meristem. Generally, it has a shallow root system further depends on the type of the soil and the water availability. The first leaf at the base of the main culm and each tiller is rudimentary, consisting of a bladeless ‗prophyllum‘. Leaves are arranged in alternate manner on the stem in two levels – one at each node, each consisting of leaf sheath, leaf blade, ligule and auricles, the former encircling the whole or part of the internode. At the junction of the leaf sheath and leaf blade, there is a triangular membranous, usually colourless ligule that tends to split with age and is flanked on either side by a small sickle-like appendage, fringed with long hairs (auricles). The leaf blade is long, narrow, 30–50 cm or more in length and 1-2 cm broad and somewhat pubescent having spiny hairs on the margins. The lamina of the uppermost leaf below the panicle (‗flag‘ or ‗boot‘) is wider and shorter than the other. The rice inflorescence is a loose terminal panicle. The spikelets are usually borne singly, but clustered forms with 2-7 spikelets together. The flower is usually self pollinated and is surrounded by lemma and palea that make up the hull or husk and remains attached to the grains in threshing. The lemma is tough, papery and may be fully awned, partially awned or awnless, while the palea is somewhat smaller and sometimes awned. Enclosed within the lemma and palea are two broad, thick, fleshy lodicules, six stamens in two alternating whorls and a pistil with two plumose stigmas on two styles. UTTARAKHAND OPEN UNIVERSITY Page 35 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 Origin: It has the origin in Southeastern Asia, but in time it has spread to every warm region of the world. The Chinese were the first to cultivate rice, and their records go back for 4000 years. Rice was introduced into India before the time of the Greeks, and very early reached Syria and Northern Africa. The first rice was grown in Europe in 1468 in Italy. The first rice in America was grown in South Carolina in 1694 from seed brought from Madagascar. Production: The global production of rice in 2012 was around 719 million tons. Out of that, 152.6 million tons (around 35 per cent) were produced in India. European countries like Italy and Spain also produced small quantities of rice but Asian continent alone accounts for more than 90 per cent of the world‘s production. Cultivation: The rice crop is grown over an extremely wide range of climatic conditions. Rice production requires; relatively high temperature; ample amount of water; close textured or relatively impervious subsoil to prevent excessive loss of water by seepage and good drainage system to allow the field to dry at the time of harvesting. Different varieties of rice vary in their season of growth, maturation period and suitability to varying conditions of soils, temperature, rainfall, altitude and adaptability to such special environments such as flooded land, alkalinity and acidity of soil and depth of standing water. Flooded fields are a prime requirement for rice production. Rice can be grown on different soil types but it prefers the heavy alluvial soils. Acidic soil pH is good for rice cultivation. Best conditions for rice to grow are high temperature (21 to 35 °C) and humidity. Harvesting: The right time to harvest the crop is when the panicles become yellowish in color and turned downward. Pre-mature and delayed harvesting are the reasons for lowering the yield. Uses: Rice is the vital part of the diet in Southeast Asia. About 90 per cent of rice is eaten as plain boiled rice with cooked pulses, curd, vegetables, fish or meat. The other Indian rice preparations are kheer, firni and pulao. In South India, fermented preparations such as dosa, idli and uppma are prepared. Rice flour is used in confectionery, ice creams, puddings and pastry. Rice starch, has broad industrial potential in the cosmetic industry, as a thickener in calico printing, in the finishing of textiles and for making dextrins, glucose and adhesives. Alcoholic beverages such as ‗sake‘ in Japan and ‗wang-tsin‘ in China are made from rice through fungal fermentation. UTTARAKHAND OPEN UNIVERSITY Page 36 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 Fig. 2.1: Some important cereal, pulse and millet crop of human food The rice husk is of little value as an animal feed because of its high silicon content. Hulls are used as a fuel, as bedding for poultry and for packing and insulation. Ash from the burnt rice UTTARAKHAND OPEN UNIVERSITY Page 37 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 hulls is used as a filler in concrete and bricks, and as a source of sodium silicate in making soaps, polishes and other cleaning agents. The bran and rice polish, by-products of the rice milling industry, are valued as a stock feed. Rice bran oil (RBO) is used for edible purposes. In China and Japan, a very fine type of paper is manufactured from the rice straw. The straw is also used for feeding cattle, as soil mulch, fertiliser and for the manufacture of strawboards. It is also employed for thatching, making hats, mats, sacks, ropes and baskets. Rice has played an important part in many ancient customs and religious and magical rituals in the East and is still associated with several ceremonies. (C) Maize Botanical Name: Zea mays Characteristic features: Maize is a tall annual grass (3 to 15 ft). The jointed stem is solid and contains a considerable amount of sugar when young. The leaves are large and narrow, with wavy margins. Extensive fibrous root system, aerial prop roots are usually formed at the base of the stem. Two kinds of flowers are produced. The tassel, at the top of the stem, bears the staminate flowers, while the cob or ear with the pistillate flowers is produced lower down on the stalk and so is protected by the leaves. Each ovary has a long silky style, the corn silk. The ovaries, and consequently the mature grains, are produced in rows on the cob. The cob is surrounded by a husk composed of leafy bracts. The grains consist of the hull, protein, endosperm and embryo. Two kinds of endosperm are usually present: a hard, horny yellow endosperm and a soft white starchy endosperm. History and Origin: Maize is supposed to have originated in Guatemala and Southern Mexico. All the principal types of maize we know today were already in existence in the pre-Columbian times. Production: The global production of maize is 872 million tons and out of that United States alone produced 273.8 million tons. The other major maize producers in the order of ranking are China 208.2 Mt, Brazil 71.2 Mt, Mexico 22 Mt, Argentina 21.2 Mt and India 21 Mt. Types: There is no knowledge about the wild species of Zea in the present. On the basis of nature of endosperm and shape of the grain maize can be broadly categorized into the following: Pod Maize (Zea tunicata): 1. Each grain is covered with a husk. 2. The plant is very leafy and the tassels are very heavy. 3. Has no commercial value because of the presence of the individual husks. Pop Maize (Zea everta): 1. Grains are usually elongate and oval, small in size, very hard and flinty with a tough hull. 2. The endosperm is mostly hard and glossy. UTTARAKHAND OPEN UNIVERSITY Page 38 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 3. Dry grains explode (expansion of endosperm) with a popping sound 4. Two kinds of popcorn occur: rice popcorn (pointed and imbricated grains) and pearl popcorn (rounded and very compact grains). 5. Has little commercial production. Flint Maize (Zea indumta): 1. Hard endosperm present outside the embryo and white endosperm as a protective layer. 2. Height ranges from 5-9 ft 3. The ears are two in number, long and cylindrical, have 8-16 rows of grains of different in color. 4. Matures early. Dent Maize (Zea indentata): 1. This is the largest species, with a height ranging from 8-15 ft. 2. Only one ear is produced in a plant. The ears are large 3. Grains are deep wedge-shaped and commonly yellow or white in color. 4. Due to its massive yield it is chiefly grown in the Corn producing areas. 5. It is the main source of fodder and commercial grain. Soft Maize (Zea amylacea): 1. The hard endosperm is entirely lacking. 2. The morphology of grains is similar to flint maize, but the size varies. 3. It is not grown on a commercial scale in the United States. Sweet Maize (Zea saccharata): 1. The entire endosperm is translucent and the starch is almost changed to sugar. 2. The grains are broad and wedge-shaped with a characteristically wrinkled surface. The grain is used in the unripe state. 3. It is adapted to the colder areas. Cultivation: Alluvium soil with high organic and nitrogen content is best suited for the production of maize. Average temperature ranging from 66-75 °F is the best for its cultivation. For the optimum growth of the plant proper sunlight and 20-in. annual rainfall are the two essential factors. Uses: The whole plant including the grain is the chief source of livestock feed. The grain is very nutritious, with a high percentage of easily digested carbohydrates, fats, and proteins and very few harmful substances. The heavy use of maize is in the US pork industry which uses about 40 per cent of the total production. Because of the absence of gluten it cannot be baked as bread. Cornmeal is often baked in cakes, such as johnny cakes, ash cakes, hoe cakes, corn pone, and the Mexican tortillas. Corn is also used in producing cornstarch, corn syrup, corn sugar, corn oil, dextrins and industrial alcohol. Various types of alcoholic beverages are made from the grain. The stock fibers are used for making paper and yarn, cigarette papers are made from inner husks and the cobs are used for fuel and as a source of charcoal. As a result of recent chemical UTTARAKHAND OPEN UNIVERSITY Page 39 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 investigations the stalks, cobs, and other waste from maize bid fair to become important sources of valuable solvents, explosives, and even a gas that can be used for home consumption. 2.3.2 Pulses Pulses are the chief source of protein to the vegetarian population. Protein is present in the large proportion then carbohydrates and fats. All the pulses belong to the family Leguminosae (Fabaceae). The characteristic feature of this family is the presence of a special kind of fruit, a legume, which is a pod that opens along two sutures when the seeds are ripe. Out of the 11,000 known species of legumes, majority of them have industrial, medicinal, or nutritive value. Legume seeds have low water content and impermeable seed coats which facilitate their storage for long duration. Because of the rich energy content legumes are particularly used in cold weather or by those who take part in rigorous physical work. The immature fruits also serve as a vegetable. Legumes are also used as field and forage crops. When plowed under they are an excellent fertilizer and greatly increase the nitrogenous content of the soil. Classification: All the species of pulses (Fig 2.1) belong to the family Fabaceae. The tabular representation (Table 2.1) of the different groups of pulses is mentioned below: Table 2.1: Different groups of most common pulses Family Tribe Genera Lentil (Less esculenta), Pea (Pisum sativum), Chick pea (Cicer Vicieae arientum), Grass pea or Khesari dhal (Lathyrus sativus) and Broad or Horse bean (Vicia faba) Hedysareae Groundnut (Arachis hypogaea) Soya bean (Glycine max), Lablab bean (Lablab purpureus), Fabaceae Common beans (Phaseolus spp.), Cowpeas (Vigna unguiculata), Phaseoleae Pigeon pea (Cajanus cajan), Horse gram (Dolichos uniflorus) and Ground beans (Voandzeia subterranea) and minor pulses such as Sword and Jack beans (Canavalia spp.) Galegeae Cluster bean or Guar (Cyamopsis tetragonoloba) (Indigofereae) Origin: According to the Chinese literature, the soya bean was cultivated between 3000 and 2000 BC. Legumes also featured in the cropping systems of the early Egyptian dynasties. Pea and lentils were present at various archaeological sites such as Hacilar, Beidha and Jarmo, dating as far back as 7500 to 6500 BC (Helbaek 1966). Pisum, Vicia and Lens were found at Neolithic sites in Greece (Renfrew 1966). The evidences suggest the domestication of common bean back in 4975 BC in the Tehuacan Valley in Mexico. Fragments of lima bean (Phaseolus lunatus) or common bean have been reported in dried human excreta (desiccated faeces or coprolites) in UTTARAKHAND OPEN UNIVERSITY Page 40 PLANT RESOURCE UTILIZATION AND CONSERVATION MSCBOT-603 coastal Peru, dating back to 3000 BC. According to Kaplan et al. (1973) the common bean and the lima bean were present in the inter-montane Peruvian Valley, dating to about 6000 BC. Nutrition: Pulses contain, almost 2-3 times more protein (about 30 % of its dry weight) than cereals, up to 60 % carbohydrates and 1-2 % fat except soya bean having up to 20 % fat. They also have niacin, thiamine, carotene, riboflavin and ascorbic acid. Pulses are rich in calcium and iron. Sprouted legume seeds are a great source of vitamin C. Production: Pulses are chiefly cultivated in the tropical and subtropical regions of the world.