Lac Culture Quadrant III PDF

Module- Lac Insect Cultivation Quadrant III Dr Abhishek Rajpurohit Assistant Professor, Department of Zoology and Environment Science Institutional Affiliation: Lachoo memorial College of Science and Technology...

Module- Lac Insect Cultivation Quadrant III Dr Abhishek Rajpurohit Assistant Professor, Department of Zoology and Environment Science Institutional Affiliation: Lachoo memorial College of Science and Technology (Autonomous) Jodhpur SECTION -EXTREMELY SHORT ANSWER QUESTION 1. Name some host plants of Laccifer lacca Butea monosperma (Palash), Zizyphus spp (Ber), Schleichera oleosa (Kusum) and Acacia catechu (Khair), are major host plants of Laccifer lacca. 2. Who first gave details of Lac insect and where? The first scientific account of the lac insect was given by J. Kerr in 1782 in Philosophical Transaction of Royal Society of London. 3. Name some states producing Lac in India. Lac is produced from the states of Bihar, Jharkhand, West Bengal, Madhya Pradesh, Chhattisgarh, Eastern Maharashtra and northern Orissa in India. 4. Give name of main steps of lac culture. The main steps involved in the cultivation of lac are: 1. Pruning, 2. Inoculation, 3. Harvesting and 4. Proper care for elimination of the enemy insects (Pest management). 5. Name some lac enemies. Some lac insect parasites which causes damage to Laccifer lacca are - Paraecthrodryinus clavicornis, Erenyctrtus dewitzi, Tachardiaephagus tachardiae, Eupelmus tachardiae, Tetrasticus purpurens SECTION - SHORT ANSWER QUESTIONS 1. What is Lac ? Lac is the only resin of animal origin, the secretion of a tiny insect, Laccifer lacca. Lac is in fact the parent of modern plastics. It is an eco-friendly, biodegradable and self- 1  sustaining natural material. Lac and its culture can help in eco-system development as well as reasonably high economic returns. 2. Explain the history of Lac The use and cultivation of lac insects has a long history in Asia, approximately it is as old as 4000 years in China. Lac is Nature’s gift to mankind and the only known commercial resin of animal origin. It is the hardened resin secreted by tiny lac insects belonging to a bug family. In order to obtain 1 kg of lac resin, around 300,000 insects lose their life. The lac insects yields resin, lac dye and lac wax. Application Lac resin, dye etc. still find extensive use in Ayurveda and Siddha systems of medicine. Greeks and Romans were also familiar with the use of lac. 3. Give an account on importance of Lac in Indian economy ? India has great potential for lac culture. India is the major lac producing country of the world, producing approximately 18,000 metric tones of unrefined raw lac annually. About 85% of the country's production is exported to various countries. The USA, Germany and Egypt are some of the major lac importing countries of the world. Export of lac from India is in the form of shellac, button lac, seed lac, dewaxed lac, bleached lac and Aleuritic acid. There is a very good increase in demand for lac worldwide is expected. It is a source of livelihood of many farmers, tribal and poor inhabiting forest and sub forest areas. 4. Give an detail account on distribution Lac insect ? India and Thailand are main areas in the world, while India has prime position in relation to lac production. Lac cultivation is introduced into Thailand from India. Over 90% of Indian lac produced comes from the states of Bihar, Jharkhand, West Bengal, Madhya Pradesh, Chattisgarh, Eastern Maharashtra and northern Orissa. Some pockets of lac cultivation also exist in Andhra Pradesh, Punjab, Rajasthan, Mysore, Gujarat, and Mirzapur and Sonebhdra districts of Uttar Pradesh. Occurrence include Burma, Cambodia, Laos, North Vietnam, China, Formosa, Indonesia, Philippines, Malaya, Pakistan, Nepal, Sikkim and Bhutan. 5. Describe some characters of Lac insect. Lac insect is a minute crawling scale insect with piercing and sucking type of mouth parts. It sucks plant sap, grows and secretes resinous lac from the body. Its own body ultimately gets covered with lac in the so called ‘CELL’. Lac is secreted by insects for protection from predators. Male is red in colour and measures 1.2 - 1.5mm in length. It has reduced eyes and antennae. Thorax bears a pair of hyaline wings. Female is larger than male, measures 4-5 mm in length and has a pyriform body. The head, thorax and abdomen are not clearly distinct. The antennae and legs are in degenerated form, and wings are absent. 2 SECTION - LONG ANSWER QUESTIONS 1. Explain the life cycle of Lac insect? The main stages of lac insect life cycle are egg, nymph instars, pupa and adult. The lac insects shows an ovoviviparous reproduction. The life cycle is completed in about six months. In favourable conditions female lays 200-500 eggs, in these eggs embryos are already fully grown when these are laid. Eggs hatch within a few hours after laying, and a crimson-red first instar nymph come out. The first nymphal stage is called as called crawler. The crawler is of approximately 0.6 x.25 mm in size. The process of emergence of nymph is called as swarming, and it lasts for 5 weeks. The nymphs crawl on branches and settle down in groups of 200-300 per square inch. At this stage, male and female nymphs both lived on the sap of the trees by their suctorial proboscis. After 1-2 days, the nymphs start secreting resin from the glands distributed under the cuticle throughout the body, except at mouth part region, breathing spiracles and anus. As soon as the resin comes in contact of air it becomes harden to make a protective covering. The nymphs moult three times inside the cells before reaching maturity. They enclosed themselves inside their resinous secretion cells, the nymphs cast off their second and third moult and mature into adult. After the first moulting appendages, eye of both male and female nymphs are degenerated.. After eight weeks, both the male and female larvae attain sexually maturity. The time period of each instar is dependent on different factors, like temperature, humidity and host plant etc. The male insect completely transformed into another form. It loses its proboscis and develops antennae, legs and a single pair of wings. It lives in a slipper shaped brood cell with a round exit operculum, through which it emerges out. The adult male is winged and moves to the other females to fertilize them. The female retains her mouth parts but is without wings, eyes or appendages. The brood cell of female is round and bigger which remains fixed to the twig. During development female insect becomes completely immovable. The female increases in size inside her brood cell and keep growing with increase in number of eggs. The female after fourteen weeks reduces in size with two yellow spots appear at the rear end of the cell. The female oviposit a large number of eggs in a body space called as Ovisac. The ovisac appears orange due to crimson fluid called lac dye which resembles cochineal. When the eggs hatch, larvae emerge and the whole process begins all over again 2. Explain the lac cultivation management in detail ? Although lac cultivation is a simple process but cultivators should have complete, 3 systematic, scientific knowledge for success. The main steps involved in the cultivation of lac are: (1) Pruning, (2) Inoculation, (3) Harvesting and (4) Proper care for elimination of the enemy insects (Pest management). Pruning In this step Pruning is done which means cutting away old, weak and diseased twigs. It induces host plants to throw out new succulent twigs and is as important in lac culture as plouging is for seed sowing in agriculture. Pruning should be done with a sharp instrument (scateur, pruning Shaw and pruning knife) to give a sharp and neat cut. Only light pruning should be carried out. Proper pruning is extremely important as it helps the growth of new and short shoots suitable for settlement of lac insects. Old and hard branches can never give a satisfactory production. The Palas tree is mature and ready for the production of lac at an age of eight to ten years, The following points should be borne in mind during the pruning  There should be no excessive pruning in order to maintain the good health and strength of the tree.  Proper cutting should be done in such a way that there should be a good shape of the tree for plenty of space for the growth of new shoots.  Branches exceeding 2”in diameter should not be cut. The most satisfactory results are obtained by cutting at a thickness of 1-2” in diameter and the thin branches under ½” diameter should be cut.  Dead and diseased branches should be removed and split or broken branches should be cut below the split or break. Normally, the time of pruning is January-February and April-May. Propagation of Lac Insects (Inoculation) Propagation of Lac insects means the process of spreading of lac insects on the same or different host plants. Propagation is done by process of inoculation of newly hatched nymphs of Lac insect. Inoculation is the method by which the lac insects are introduced on to a host plant. Inoculation should be done on trees which are being prepared for such purpose by pruning in due time. Inoculation is of two types. i) Natural inoculation: This type of inoculation occurs naturally. It is very simple and common process, when the swarmed nymphs infect the same host plant again. Natural inoculation, being repeated on the same host, makes in host plant weak, and thereby, nymphs do not get proper nutrition. Also in natural 4  inoculation, it is not sure that uniform sequence of inoculation take place. Therefore, natural inoculation should be discouraged. ii) Artificial Inoculation: Artificial inoculation is done by the agency of man artificially. The main idea behind the artificial inoculation is to check the drawbacks of natural inoculation. In this method, the host plants are first of all pruned in Jan. or June. In artificial inoculation, brood twigs are cut in size 20 - 30 cm in length. Then, the cut pieces of brood twig are tied to fresh tree twigs in such a way that each stick touches the tender branches of trees at several places. The nymphs swarm from brood and migrate to tender and succulent twigs and infest them. Following swarming, the brood twigs should be removed from the host plant, as this would decrease the chance of pest infestation. For Palas trees. the quantity of brood lac required for a tree depends upon the kind of tree and the size and number of suitable branches. Approximate weights of brood lac required for inoculating one medium sized tree of the following hosts are: Palas – 0.5-1.0 kg; ber – 1-2 kg; khair – 1-2 kg; kusum – 5-10 kg. The general time period for the inoculation of lac insect is June-July -- Inoculation of Palas trees from the Baisakhi brood to produce Katki Crop, October-November -- Inoculation of Palas trees from the Katki brood for production of Baisakhi Crop Harvesting / Cropping While harvesting the lac crops, the following points should be take care: (i) After maturation only Lac crops should be obtained. (ii) There should be no premature cutting of lac, it will affect the quality of brood lac, since the female lac insects is ready to lay eggs and will get cut off from their food supply from the host tree as a result weak, emaciated and unhealthy progeny will be obtained. (iii)In pruning or cropping a host tree, like kusum and certain species of Ficus, the general health of the tree must be maintained and its frame increased as far as possible. (iv) All dead and diseased branches should be cut off. Lac Crop Management Following points should be carefully followed by the cultivators during lac crop management:- (i) Lac crop under field condition is monitored regularly for possible infestation of enemy insects, predatory animals and fungi. (ii) Pest management depend upon crop season, host tree and environmental conditions. 5  (iii) Fully mature and healthy broodlac free from pests or enemy insects should be used. (iv) Correct amount of brood lac, neither less nor more, should be used for infection. (v) The quantity of broodlac used usually depends on the size of the tree. In case of Palas trees, 300 gms while in cases of small trees upto about 1 Kg lac is obtained (vi) Selected brood lac in lengths of about 6 to 12 inches should be first tied into bundles of 2 to 3 sticks and then such bundles tied on to the branches of the trees at such places that the twigs above (with 15 to 20 times the total length of brood sticks used in the bundle) get full infection. This will ensure full and uniform distribution of the brood and consequently full and uniform infection of the tree. (vii) Brood meant for inoculation should not be kept for long and used immediately after crop cutting. Usually most of the lac larvae emerge from the brood within a week or ten days from the time of first emergence and to get best result inoculation should not be delayed beyond 2-3 days of noting larval emergence from the broodlac. (viii) Tying of the brood lac stick should be done securely on the upper surface of branches. This will prevent falling of twigs and provide full contact for quick and easy crawling of the nymphs. One should keep a watch on the brood lac dropping down. (ix) Sometimes due to bad weather, swarming of nymphs from brood is prevented. Hence, the room storing brood lac sticks is moderately heated to induce swarming, and then sticks are tied. (x)Usually self-infection should be avoided unless forced by circumstances (xi) Generally, cultivation of kusumi in rangeeni area and vice versa should be avoided. (xii) Brood lac from a particular host used year after year is likely to deteriorate in quality. Therefore, alternation of brood and host give production of a better quality of brood lac. (xiii) While inoculation is going on, sometimes it will fall to the ground due to a different reasons such as the activity of squirrels and rats, and therefore, there is a need to keep proper watch on infected trees and then and put such fallen bundles back on the tree. (xiv) Brood lac bundles should be kept on the tree for the minimum period required for complete infection. not for more than two or three weeks. If kept longer there is the danger of a large number of enemy insects emerging from the empty (phunki) brood lac sticks and starting heavy infestations in the field. 3. Describe the composition and economic importance of Lac ? Lac Composition  The major component of sticklac is the resin. It occupies 70-80% of total composition. Resin is a polyester complex of straight- chain hydroxy fatty acids of C14 – C18 carbon chain, mono- and di – hydroxy acids along with hydroxy terpenic acids.  The Resin can be fractionated into soft and hard components by exhaustive 6  extraction with ether. Both soft and hard resins can be further fractionated by successive extraction with organic solvents.  Soft resin part contains free acids and neutral materials including the yellow dye, erythrolaccin while hard resin comprises of equivalent amounts of aleuritic acid, an isomer of aleuritic acid and lacollic lactone.  Remaining components are dye, sugars, proteins, and soluble salts, wax, sand, woody matter, insect bodies and other extraneous matter, a volatile oil is present in traces. 1. Wax –It is a by-product in the manufacture of dewaxed shellac, commercially known as Shellac Wax. 2. Red Dye–A water soluble red dye, laccaic acid, and an alkali and spirit soluble yellow dye, erythrolaccin is present in lac. Lac dye is obtained by extracting sticklac with water and sodium carbonate solution and precipitating with lime. It gives bright red and scarlet shades which are somewhat faster than cochineal. 3. Crude lac- It is obtained by scraping the resinous encrustations from harvested twigs, It is seldom used without refining. 4. Seed Lac Sticklac is crushed by roll mills and washed with water in cup-shaped stone vats or steel barrels. It is then dried on cemented floors away from the direct rays of the sun and finally winnowed. The water soluble colouring matter is removed during washing. Washed lac or seedlac, thus obtained is in the form of grains, yellow or reddish brown in colour. The lighter impurities float on the surface and can be easily removed. Lac Insect products and their use  Lac dye Lac dye of colour varies between purple red, brown and orange is obtained from lac insect. This dye is used for colouring various products like wool, threads, silk and food and beverages industry.  Lac wax Lac wax is a mixture of higher alcohols, acids and their esters. It is used in various products like polish of shoes, floor, automobiles etc, Food and confectionary, and drug tablet finishing, lipsticks, children colourful Crayons  Shellac Commercial lac is called as Shellac. It is a natural, nontoxic, hard, tough, amorphous, brittle, physiologically harmless and edible resin. Shellac is a resin containing small amount of wax and a substance responsible for its characteristic pleasant odour. It is insoluble in water, glycerol, hydrocarbon solvents and esters, but dissolves readily in alcohols and organic acids and slightly heavier than water and its natural colour varies from dark red to light yellow. When slowly heated, it softens at 65-70oC and melts at 84- 90oC. 7  Use: o Lac is used as a filling material in the ornaments by jewellers and goldsmiths. o It is used in different edible products like fruit coatings, e.g. for citrus fruits and apples, parting and glazing agents for sweets, marzipan, chocolate etc. o It is also used in preparation of toys, buttons, pottery and artificial leather. o It is used as binder for mascara, nail varnish additive conditioning shampoo, film forming agent for hair spray, micro-encapsulation for perfumes. o It is used as coatings for medicinal tablets o It is used in manufacturing of photographic material, lithographic ink and for stiffening felt and hat material. 4. Write a short note on a) Stains of Lac insect In India, mainly there are two distinct strains of Lac insect: kusumi and rangeeni. The life cycle of lac insects take about six months, hence, two crops a year can be obtained. KUSUMI STRAIN RANGEENI STRAIN This strain is grown on kusum or on other This strain thrives on host plants other than host plants using kusumi brood kusum The crops have been named after Hindi months during which these are harvested. In case of kusumi strain, two crops are: In case of rangeeni, two crops are: i) Jethwi (June / July) i). Karrtiki (October / November) ii) Aghani (January / February). ii). Baisakhi (May / June). The lac of kusumi crops is harvested after The lac of rangeeni crops is harvested while it maturing is still immature. 10% of lac production is contributed by It ontributes about 90% of lac production kusumi crops Kusumi crop lac is considered of superior In comparison to Kusumi crop, rangeeni lac is quality resin, because of the lighter colour of considered inferior quality resin, and it’s get resin, and it fetches better price. lesser price. b) Hostplants of Lac insect Lac insects grow on twigs of certain host plants species, feeds on the plant sap, and secrete lac resin from their bodies. Although lac insect is a natural pest on host plant but they are not considered as pest because they produces a useful product. Although there are numerous host plants of lac insect but Butea monosperma (Palash), Zizyphus spp (Ber), Schleichera oleosa (Kusum) and Acacia catechu (Khair), are major host plants. The market demand of Kusumi lac is more and have higher price in market. The ber tree, siris (Albizzia sp.), Prosopis juliflora are identified as good host for kusumi brood lac. Some other common host plants in India are Acacia arabica (Babool), Acacia auriculiformis (Akashmani), Zizyphus xylopyrus (M.P. & U.P.), Shorea talura (Mysore), Cajanus cajan (Pigeon-pea or Arhar), Grewia teliaefolia (Assam), Albizzia lebbek (Siris), Flemingia macrophylla (Bholia), Ficus benghalensis (Bargad), 8 Ficus religiosa (Peepal) etc. 5. Explain different problems in lac cultivation in detail. Lac Enemies Insect Enemies of Lac insects The main enemies of lac crop are the insects. These insects are serious and damaging pests and can reduce up to 30-40% of lac yield. The insects damage the lac crop is two ways: a) As Parasites: Lac insects population up to 5-10% are parasitized and killed by small winged eight species of insect belonging to family chalcidoidae order Hymenoptera – Paraecthrodryinus clavicornis, Erenyctrtus dewitzi, Tachardiaephagus tachardiae, Eupelmus tachardiae, Tetrasticus purpurens etc. These insect pests lay eggs in lac cells. Their grubs on hatching feed on lac insects within the cells. b) As Predators: The predators cause major damage (up to 35%) to lac crop. There are numerous predators on Lac insect but three main are: (1) Chrysopa spp.: Commonly known as lac wing fly, order Diptera (2) Eublemma amabilis Moori: commonly known as white lac moth, order Lepidoptera (3) Holocerca pulverea Meyr : commonly known as black lac moth, order lepidoptera The white lac moth is more destructive on trees; while black lac moth, on the stored lac. These predator moths and fly lay their eggs on the lac encrusted twigs. On hatching, their larvae make their way inside the lac encrustation and feed on the lac insects as well as on lac encrustations. Control Measures for the control of insect enemies of lac are:  Before brood lac should be used for inoculation it must be healthy and pest-free.  Enclosing of broodlac for inoculation in 60-80 mesh wire gauze baskets, c. 30 cm x 7 cm in size. This method is particularly used for areas where lac cultivation is being introduced for the first time. The baskets permit free exit to lac larvae but exclude enemy insects. Proper management of host plants with a view to ensure their vitality and vigour helps to reduce damage by parasites.  The twigs for inoculation should be cut just before swarming to get healthy brood.  Scrapping of encrusted lac from twigs should be done as soon as possible, and lac, thus obtained should be immediately converted into seed lac and not left near the inoculated lac hosts.  Immersion of freshly harvested sticklac, not wanted for brood, as well as phunki lac (i.e., broodlac after larval emergence is complete) in running or deep stagnant water  Scraping of lac from twigs immediately after harvesting and killing larvae and 9  pupae of the pests by burning, crushing, drowning or by fumigation with carbon bisulphide (1 oz./10cu.ft. of space) before storage.  Infected stick lac should be destroyed along with predators and pests. Vertebrate enemies of lac insects Some vertebrates also can cause damage to lac crop some of the important vertebrate enemies are squirrels and rats and they can cause damage upto 50% of total lac yield. Squirrels usually damage in daytime while rats are nocturnal and the damage usually occurs in night. When the crop is at maturity stage, these pests gnaw the mature lac encrustation on the tree and the brood lac tied to trees for inoculation and consumes the full grown lac female insects with plenty of eggs inside them. Besides these vertebrates monkeys also cause some damage to lac encrustations. Control It is very difficult to control the squirrels and rats under the open field conditions where lac is cultivated. However scaring away of these animals or poisoning them may be solution. 10