INTRODUCTION TO LAC CULTURE
Almost all the scale insects are harmful as they suck the sap from the plants. Few of them are also beneficial and Lac-insect is one among them. Lac is a resinous protective secretion from of the lac insect. This secretion has great commercial value. So, lac insects are cultivated and lac is collected from the host plants. Hence, Lac culture is the commercial production of lac which includes regular pruning of the host plants, propagation of lac insects and the processing of the lac.
Lac is the gift of nature to mankind and is the only known commercial resin of animal origin. It is the hardened resin secreted by tiny lac insects belonging to a bug family. To produce 1 kg of Lac resin, around 300,000 insects lose their life. The lac insects yields resin, lac dye and lac wax.
Application of these products has been updating with time. Lac still finds extensive use in Ayurveda and Siddha systems of medicine. Lac has the unique properties of being eco-friendly, biodegradable and self-sustainable. Moreover it is a natural material and thus currently it has assumed special importance. Since lac insects are cultured on host trees which are growing primarily in wasteland areas, promotion of lac and its culture can help in eco-system development with reasonably high economic returns. It also acts as a source of livelihood for tribal and poor sub-forest areas.
History of Lac
Lac is been in use in India since Vedic period. Its earliest reference is found in Atharva Veda. The name lac seems to be derived from the word Laksha meaning one lac in Sanskrit which is suggestive of the large number of insects settled on young succulent shoots of the host plant. The great Indian epic ‘Mahabharata’ also mentions a ‘Laksha Griha’, an inflammable house of lac, cunningly constructed by ‘Kauravas’, for the purpose of burning their great enemy ‘Pandavas’ alive. There are also evidences that ancient Greek and Roman knew the use of lac.
Other given names
Father Tuchard studies lac insect for the first time in 1709. The name Coccus lacca was given by Kerr in 1782. Later Chaterjee called the lac-insect as called as Tachardia lacca or Kerria Lac and finally the name Laccifera lacca was given.
There are six genera of lac insects, out of which only five secrete lac but only one of them, Laccifer secretes recoverable lac. The commonest and most widely occurring species of lac insect in India is Laccifer lacca (Kerr) which produces the bulk of commercial lac.
Distribution in India and abroad
India held virtual monopoly of lac until 1950 and accounted for about 85% of the world’s production of sticklac. After 1950, Thailand became the main competitor of India. Other countries like Africa, Australia, Brazil, Burma, Sri Lanka, China, France, Japan and West Germany also produce lac.
In India major lac producing regions are Assam, Bengal, Bihar, Delhi, Gujarat, Hyderabad, Kashmir, Madhya Pradesh, Chennai, Coimbatore, Mysore, Rajasthan and Uttar Pradesh. Over 90% of Indian lac produced comes from the states of Bihar, Jharkhand, West Bengal, Madhya Pradesh, Chhattisgarh, 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.
LAC CULTURE IN INDIA
Lac resin is natural, biodegradable, nontoxic and hence finds application in food, textiles and pharmaceutical industries. As now-a-days, there is increased stress on the use of eco-friendly, safe material for human contact and consumption lac is high in demand. Lac production is a source of livelihood for tribal and poor people of forest and sub forest regions of India.
India held virtual monopoly of lac until 1950 and accounted for about 85% of the world’s production of sticklac. Currently it has come down to 50-60%. After 1950, Thailand became the main competitor of India. Other countries like Africa, Australia, Brazil, Burma, Sri Lanka, China, France, Japan and West Germany also produce lac.
Still India has great potential for lac cultivation. The areas for lac cultivation can be classified into three categories which are as follows:
Regular lac cultivation areas: Only 20-25% of the total available host trees are being used
Moderate lac cultivation areas: Around 10-15% of available host trees are being used
Un-utilized areas: Though host trees are available, they are not utilized due to lack of knowledge and awareness
On the whole only 15% of the total available lac host trees owned by farmers are used for lac cultivation. There are vast untapped trees,, which are ecologically favorable for lac production in our country. If exploited properly in scientific manner these areas would enhance the lac production capacity of India.
The production of raw lac in India is approximately 20,000 metric tonnes per year. Lac culture has been a good source of foreign revenue. The major lac producing states in India are Jharkhand- 57%, Chhattisgarh- 23% and West Bengal- 12%. Other minor producers include Odisha, Maharashtra, Assam, Andhra Pradesh and Uttar Pradesh. Other states like Odisha, Madhya Pradesh, Punjab, Rajasthan etc. have shown increased production of lac. Approximately three million tribals inhabiting in these areas have taken up lac cultivation.
In 1925, Indian Lac Research Institute (currently named as Indian Institute of Natural resins and Gums) is been established at Namkurn, Ranchi. This institute produces good quality of white lac. Indian White lac is supposed to be better than red or other colored lac as the colored lac leaves stains at the places where they are kept.
India fetches about Rs. 120-130 crores of foreign currency through export of lac every year. Out of total lac produced in India 85-95% is exported especially to Britain, USA, Russia and West Germany. Export of Lac from India is mainly in the form of shellac, button lac, seed lac, dewaxed lac, bleached lac and Aleuritic lac.
While enhancing production quantity, quality also needs equal emphasis to meet the national and international demands. The lac suffers quality for the reasons like untimely harvesting, lack of appropriate storage, primary processing soon after harvesting and lack of appropriate processing machinery. These problems need urgent attention and can be addressed by adopting scientific recommendations developed by Indian Institute of Natural resins and Gums.
LIFE CYCLE OF LAC INSECT
The life cycle of lac insect mainly depends on the ecological factors of the region like the temperature, humidity and the host plant species. It includes four stages namely, Egg, Nymph instars, Pupa and adult. The egg reached the adult stage within six months. The following are the stages involved in the reproduction of lac insects,
Lac insects are ovoviviparous types. The females get attached to the host plant inside the resinous mass. The male insect comes out of its resinous mass by pushing the operculum of the anal opening and then walks over the resinous covering of the female. This walking fertilizes the female within. One male lac insect is capable of fertilizing many females.
After the fertilization, the female grows rapidly until it begins to lay eggs. By the time female starts to lay the eggs, its body contracts on the ventral side and gradually vacating the place for the eggs to be accommodated inside the resin cell. After laying the eggs the female secrets the lac resin at a faster rate. After about 14 weeks, female completes shrinks in size allowing the light to pass into the cell and onto the eggs.
At this stage, two yellow spots appear at the rear end of the resin cell. These spots gradually enlarge and turn orange in color. This indicates the completion of egg-laying by the female lac insect. After laying the eggs the female lac insect dies. Now the resin cell with eggs is called as ovisac. The ovisac appears orange in color due to the crimson fluid called the lac dye. This indicates that eggs are about to hatch in a week.
After six weeks, the eggs are hatched into first instar larvae called crawlers. These larvae emerge our in very huge numbers and this emergence is termed as swarming. The first instar larva is broad, red-coloured and boat-shaped. It has paired antennae, ocelli and sucking type of mouth parts with proboscis. These larvae prefer succulent shoots as their host. The settled larvae suck the sap from the host and start to secrete resinous substance all over their body.
As the resinous secretions come in contact with the air, it becomes hard and forms a coating over the body of the larva and now this covering is called cell. Within the cell various life processes like the growth of larva and morphological changes takes place.
Inside the cell, the larvae undergo three moults. After the first moult, both the female and male nymphs lose their appendages, eye and become degenerate. The female once inside the cell will never move on the other hand the male comes out through the operculum of the anal opening.
After about 6-8 weeks the stationary life of larva metamorphoses into adults having cast-off the second and the third moults. Only the male undergoes complete metamorphosis, it loses its proboscis, develops antennae, legs and a pair of wings. The females undergo incomplete metamorphosis. They retain her mouth parts but fail to develop any wings, eyes or appendages. Female becomes an immobile organism with little resemblance to an insect. They become little more than egg producing organisms.
The sex can be determined even during the early stages of development. As in case of males the growth is more on the longitudinal axis and in females the growth is more in vertical axis. The life span of the female is longer than that of the males. Most of the lac is secreted by the females. The life cycle occurs twice in one year on the same plant.
- Write down the scientific classification of Lac insect.
- Write the importance of lac and position of India in its prouction.
- Discuss the history and other names gives to Lac insect
- Explain the importance of lac with reference to India.
- Write the economics of lac production in India.
- How can the lac production be increased in India.
- Discuss the life cycle of Lac insect.
- Draw a neat labelled diagram of the life cycle of lac insect.
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