Unit 1: Vegetable Crop Production and Management PDF

Unit 1. Vegeteable Crop Production and Management 1.1.Importance, problems and prospects of vegetable crop production in Ethiopia 1.2.Environmental factors influencing vegetable production 1.3 Classifications of vegetable crops 1.4.Types of vegetabl...

Unit 1. Vegeteable Crop Production and Management 1.1.Importance, problems and prospects of vegetable crop production in Ethiopia 1.2.Environmental factors influencing vegetable production 1.3 Classifications of vegetable crops 1.4.Types of vegetable crop production System 1.5.Principles of vegetable crops management  1.1. Importance, problems and prospect of vegetable crops production in Ethiopia Vegetables ▪ Plants whose fruit, seeds, roots, tubers, bulbs, stems, leaves, or flower parts are used as food ▪ Vegetables are diverse in their growth cycles – Annuals Biennials Perennials ▪ Herbaceous are plants that that have no persistent woody stems above the ground  Vegetables are usually harvested fresh - when their moisture contents are high Vegetables are seasonal, perishable, and bulky in relation to their volume They require intensive management They are vulnerable to damage  Importance ▪ The most important vegetable crops in Ethiopia ▪ The major vegetables produced for domestic consumption  Green beans and peas are mainly produced for export purposes ▪ Smallholder farmers: are farmers that own an average landholding size of 0.9 hectare  Vegetables ▪ Have a relatively higher value ▪ Has a higher potential to increase employment and household income Profitable activity Productivity of vegetables is often higher Intensively managed Highly perishable Need to be stored and transported carefully An increased consumption of vegetables: ▪ Reduces hidden hunger ▪ Vegetables are rich sources of vitamin A, vitamin Vegetables such as spinach, tomato, etc. are C (ascorbic acid), thiamine, niacin, folic acid and often good sources of iron, zinc, and iodine beta carotene ▪ Beta carotene is responsible for the normal functioning of the visual process and the structure of the eye  Vegetables are also raw materials for local processing industries. Increased demand for vegetables has encouraged investment in the sector both by national and international commercial producers  Potentials and Opportunities Ethiopia has: ▪ Favourable climate for production of various vegetable crops abundant labour ▪ Vast land and water resources ▪ Suitable regions for production of various types of vegetables Key terms Agro ecology: relationships organisms have among themselves and with the surrounding physical environment in agriculture Alpine Climate: Climate of high mountain regions/highlands Humid tropics: Regions with relatively high temperature throughout the year and where rainfall exceeds evapotranspiration for 75% of the year In Ethiopia: ▪ Vegetable production yields per unit area ▪ Amount of land used for production of the crops, is increasing This is because of: ▪ Increase in public awareness about health benefits of vegetables ▪ Small scale irrigation ▪ Government support for investors ▪ Incentives in the form of tax exemptions and other related benefits ▪ Local demand for vegetables ▪ Export of vegetables  Constraints ▪ Inadequate knowledge of improved methods of production and marketing ▪ Low consumption of vegetables ▪ High cost of production inputs like fertilizers, improved seeds and pesticides ▪ Poor management of vegetables ▪ Small size of vegetable processing facilities ▪ Poor soil fertility ▪ Pests ▪ Drought ▪ Postharvest losses ▪ High price of fuel for pumping water for irrigation  Environmental Factors Influencing Vegetable Production ▪ Climatic: Temperature Light Precipitation ▪ Soil : Chemical Physical Nutritional status of the soil and topographic factors ▪ Biotic factors: Insects Diseases Weeds  Temperature Temperature affects: Photosynthesis Respiration Transpiration Germination Flowering Photosynthesis, respiration and transpiration increase with increasing temperature up to a certain point ▪ Temperature also influences the shift from vegetative growth to reproductive growth stage ▪ The effect of temperature on transition from vegetative to reproductive growth stages depends on the specific types of vegetable crops grown ▪ Temperature determines types of crops that grow successfully in a given location and their yield levels ▪ Crops that originate in temperate regions have lower temperature requirements ▪ Crops originating in tropical regions require warmer temperatures Soil temperature directly affects: ▪ Seed germination ▪ Root development ▪ Absorption of nutrients and water by the roots ▪ Warmer soil temperature generally increases the rates of these processes. ▪ The size, shape and quality of harvestable parts of vegetable crops are also affected by soil temperature ▪ Tropical and sub-tropical vegetables may be damaged at temperatures below 10 0C, This is called chilling injury  Some vegetable crops require exposure to low temperature before moving from vegetative to reproductive growth stages. This process is known as vernalization Eg : Biennials and some of the cool season vegetables Water Fresh vegetables contain a high level of water 80% and 90% of their weight is made up of water production of each kg of dry matter, 322L of water is required  Role Of Water in Crop Production Germination and growth of crops start only when water is available Organic and inorganic compounds absorbed by plants are dissolved in water Water is required in the process of photosynthesis Water is important in cell division, enlargement and turgidity  Too little or too much water is harmful for plant growth Water shortage during critical growth stages directly affects yield Insufficient water supply during early plant growth stages results: Stunting Reduced yield Excess moisture from rainfall or irrigation: ▪ Damage vegetable seedlings ▪ Wash away plant nutrients from the soils ▪ Erode soils and cause flooding Light Key element in photosynthesis Plants grown in full light develop vigorously with high chlorophyll amount and high photosynthetic activity  Plants grown in reduced light have lower chlorophyll amounts and are often succulent Succulent: a plant such as a cactus in which the leaves and stem are thick and can store a lot of water  The length of the light period (day length) and its quality varies according to: Season of the year Altitude Latitude Humidity ▪ Refers to the amount of water vapour in the atmosphere ▪ High levels of atmospheric humidity is often associated with incidence of crop diseases and pests ▪ Humidity affects plant growth and development through its effect on plant transpiration from leaves ▪ In humid atmosphere, the stomata open and allow diffusion of carbon dioxide, oxygen and water vapour ▪ This allows active photosynthesis and nutrient absorption ▪ Very high humidity could cause increased germination of certain fungal species ▪ Excessive humidity could also close stomata ▪ Low humidity is also harmful for the plant ▪ It may result in increased transpiration and this may attract some pest types Vegetables that require High Humidity Vegetables that require Low humidity Cabbage Peppers Carrots Sweet potatoes Lettuce Watermelon Onion Cucumber Spinach Tomato Broccoli Squash Pumpkin Potatoes The Process of Photosynthesis  Altitude ▪ Temperature and rainfall of an area are determined by the altitude of the area in relative to sea level ▪ With 100m increase in altitude, there is 0.6 0C decrease in temperature ▪ This affects vegetable production ▪ Vegetables vary in their temperature and water requirements ▪ In Ethiopia, the highlands have high rainfall and low temperature ▪ This is often suitable for vegetable production ▪ The lowlands have lower rainfall ▪ Higher temperature and are less suitable for vegetable production Soil Soil type, fertility and structure contribute to the growth and yield levels of crops. The type of soil determines: Soil water shortage Soil compaction Soil texture refers to the particle size the soil contains Key terms ▪ Compaction: is process in which soil is pressed down, (e.g., by heavy loads) and becomes very firm with little space between its particles ▪ Pore space: refers to the space between soil particles. It is used for air circulation and water storage. Roots grow into the soil through the pore space Biotic Factors Vegetables can be classified into different groups. 1. Root vegetables: These are vegetables whose roots are consumed as food 2. Leafy Vegetables: These are vegetables grown for their leaves or stems 3. Flower Vegetables: The flowers of ‘flower vegetables’ are consumed Warm season (tropical and sub-tropical) vegetables ▪ Adapted to temperatures ranging from 18 to 29oC ▪ Grow well only in warm areas ▪ Cannot tolerate frosts ▪ They are sometimes called tender plants  Cool season (temperate) vegetables ▪ Grow well in relatively cooler regions ▪ Cool season vegetables are referred to as ‘hardy plants’ ▪ Can tolerate frost without injury  The sizes of cool season (temperate) vegetables are often small They are shallow rooted They respond more readily to nitrogen fertilizer than do warm season crops Vegetables classification based on life cycle 1. Annuals ▪ Complete their life cycle in a single year ▪ Most vegetables are annuals 2. Biennials ▪ Require two growing seasons to complete their life cycle are called biennials ▪ In the first growing season, biennials produce their vegetative parts, and during the second season, they grow their reproductive parts ▪ Many biennials are sensitive to temperature, particularly for flowering 3. Perennials ▪ Grow for more than two growing seasons ▪ These vegetables can stay in production as long as ten years  Types of Vegetable Production Systems Gathering of wild vegetables ▪ Collection of edible parts from wild vegetable crops ▪ Several weeds are also consumed as vegetables including Amaranthus Vegetables grown mixed with cereal crops ▪ Ethiopian mustard grows mixed with maize crop ▪ Taro and kale can grow mixed with coffee plants ▪ Vegetables are most of the times is grown in places that cannot be used for growing cereals. ▪ The amount of vegetables grown in cereal fields is small Home gardening ▪ Practice of allocating land close to the homestead for vegetable production ▪ Can also be a source of income for the household ▪ Various vegetables including fruit, seed, leafy and root vegetables are grown together ▪ Such home gardens are very common in the Ethiopian smallholder farming systems ▪ Household organic wastes can be used to fertilize the plots close to the house Commercial vegetable production ▪ Mainly market-oriented production ▪ Common around urban centres ▪ Supplies vegetables for the urban population ▪ Intensively managed with generous use of agricultural inputs Principles of Vegetable Crops Management