Lac (LAKSA & ALAKTAKA)

Laksha is obtained from plaksa, nyagrodha etc.  It is a banned item in the trade during the ancient times.  Laksa is red in clour.  Kesava paddhati (28/4) indicated ‘laksa-udaka’ for cleansing the wounds due to sastraghata, raktasrava and asthibhagna. Kousikasutra (28/14; 35/24; 38/9; 76/8) prescribed ‘laksastra’ for oral administration in case of sadyovrana (injury).  Panini and ighantu have considered ‘jatu’ as laksa.  In brhat trayi works laksa is mentioned at places while describing the qualities of rakta and artava.  Caraka indicated it for the management of urahksata – UROMATVA KSATAM LAKSAM TVARAYA JAYET –  (C.S.Ci.).  In bhavaprakasa we come across mentioning of laksa under haritakyadi varga.  The synonym vrksamaya indicates that the ancient Indians have the knowledge of its production from a tree as exudates.  Alaktaka is the extract from laksa.  Actually laksa is produced by lac insect on various trees.  Both laksa and alaktaka may be compared to lac and ighant.

Research –

Indian Institute of Natural Resins and Gums (IINRG) (formerly Indian Lac Research Institute (ILRI)) is a nodal Institute at national level for research and development on all aspects of lac and other natural gums & resins (excluding production) such as harvesting/ tapping, processing, product development, training, information repository, technology dissemination and national/international cooperation. Realizing the strategic importance of lac, the then Imperial Govt. of India constituted the Lindsay- Harlow Committee in 1920, to look into all aspects of the country’s lac trade and its development. On the suggestions of this Committee, lac merchants organized themselves into the Indian Lac Association for Research, under the aegis of which, the foundation stone of Indian Lac Research Institute (ILRI) was laid at Ranchi on September 20,1924. Subsequently, on the recommendation of the Royal Commission on Agriculture, the Indian Lac Cess Committee (ILCC) was constituted, which took over the reigns of the ILRI on August 1, 1931.The ILCC also organized and maintained the London Shellac Research Bureau, UK and Shellac Research Bureau and Polytechnique Institute of Brooklyn, USA. As a result of reorganization of agricultural research and education in the country, the ICAR took over the administrative control of the ILRI from April 1, 1966. This is one of the oldest Institutes within ICAR, having completed 84 years of fruitful service to the nation. The institute mandate has been expanded in the year 2007 to look after important issues related to all natural resins & gums of Indian origin. Accordingly ILRI has been renamed as Indian Institute of Natural Resins and Gums (IINRG). The Institute is known by this name since Sept.20, 2007.  It is located 9 km. south-east of Ranchi city, on the Ranchi-Jamshedpur highway NH-33 (courtesy – IINRG)

Lac Insects – There are several lac insects, some of which secrete highly pigmented wax. The Indian lac insect Laccifer lacca is important commercially. It is found in tropical or subtropical regions on banyan and other plants. The females are globular in form and live on twigs in cells of resin created by exudations of lac. Sometimes twigs become coated to a thickness of 1.3 to 3.4 cm.  The lac insect (Laccifer lacca) secretes a sticky, resinous material called lac, from which shellac and a red dye are produced.

Any of the species of Metatachardia, Laccifer, Tachordiella, Austrotacharidia, Afrotachardina, and Tachardina of the superfamly Coccoidea, order Homoptera that are noted for resinous exudation from the bodies of females. Members of two of the families viz. Lacciferidae and Tachardinidae appear to be more concerned with lac secretion. These insects have a global distribution excepting Europe.

Of the many species of lac insect, Laccifer lacca, (=Tachardia lacca) is the commercially cultured lac insect. It is mainly cultured in India and Bangladesh on the host plant, Zizyphus mauritiana and Z. jujuba. The insect starts its life as a larva or nymph which is about 0.6 mm long and 0.25 mm wide across the thorax. The young settles down on a suitable place of the host plant gregariously. On the average some 150 of such larvae may be present per square inch of the twig. They have the typical piercing and sucking mouthparts as in all other Homoptera. A day or two after settlement, the larvae start secreting lac all around the body excepting the rostrum, the brachial plates and tip of the abdomen. Thus it gets encased in a cell of lac which gradually increases in size along with the increase in size of the insect. The insect moults twice before reaching maturity. The duration of each larval inster depends on environmental factors, such as, temperature, humidity, host plant etc. The male larvae produce elongated lac cells while the females produce oval.

After the first moult, the male as well as the female larvae lose their legs, antennae and eyes. After the 3^rd moult, the larvae pass on to the so-called pupal stage. During this stage the mouthparts become atrophied in male insects and they stop feeding. The male lac insect may be winged or wingless and they copulate with the females while they are still in encased condition.

During development, the female larvae lose their appendages after the first moult. As the lac insects remain close together, lac secretion from adjacent cells coalesces with each other and forms a continuous encrustation on the tree branch. Besides lac’s use as sealing wax, it is widely used in varnishes.

Lac culture Very little is known from literature about the time when man first started culturing lac insects. From Atharva Veda it appears that knowledge about the lac insects, their biology, nature of secretion, and the uses of the secretions of the insect was known to man from the prehistoric time. In Sanskrit literature the tree, Butea monosperma has been referred to as the Laksataru, which is known to be the most common lac host.

In the Medieval period lac was probably introduced in Europe by the Spaniards from India to be used as a dye and also in the fabrication of Arabian medical preparations. India is still being regarded as the principal lac producing country of the world. Burma appears to have been involved in lac trading since sixteenth century. Lac culture in China probably dates back to 4000 years. With the development of silk industry there, the Chinese were also engaged in lac culture. They used lac for dyeing the silk. Lac was also used in dyeing leather goods. In Thailand lac cultivation is of recent introduction and it dates back to the fifties of the 20^th century. Thailand generally has an export market to Calcutta where shellac is extracted from sticklac.

In Bangladesh lac culture dates back to the same period as in India. In the Nawabganj district lac culture is one of the regular occupations of many local people. However, only the sticklac is produced. In Talaimari areas of Rajshahi city there are more than 100 cottage industries where shellac is extracted from the sticklac produced in Nawabganj.

Plants such as, Zizyphus mauritiana, Z. jujuba, Butea monosperma, Schleichera oleosa, Acacia arabica, A catechu, Cajanus cajan, Ficus benghalensis, F. cunia, and F. religiosa commonly horbour the lac insect Laccifer (=Tachardia) lacca. In Bangladesh lac culture is restricted to Z. jujuba although some sticklac is occasionally collected from the wild from other host plants. The finest quality of shellac is obtained from kusum tree, S. oleosa.

Lac culture involves two important steps: (i) inoculation, and (ii) cropping. Inoculation can be carried out through self-infection or artificial infection. In any case the brood lac is necessary. Artificial inoculation is most suitable immediately after crop cutting. In doing so, the brood lac (10 to 30 cm long) are to be tied in bundles of 2 or 3 sticks and in turn they should be tied up to the branches of the host tree. Care should be taken while tieing the bundles so that they have contacts with the branches. The brood lac bundles should be kept on the host tree for 2-3 weeks. If kept longer, ie even after the complete emergence of the lac larvae, there is the danger of a large number of enemy insects emerging from the empty brood lac sticks. Lac crops should be reaped only when mature.

There are four seasons of lac cultivation and according to the Bengali calendar, they have been named as Kartiki, Aghrani, Baisakhi, and Jesthi. The crop period, from inoculation to harvesting, for Kartiki, ranges from July to November, for Aghrani,from July to February, Baisakhi, from November to July, and Jesthi, from February to July. In Nawabganj areas lac is cultivated only once a year, ie Jesthi. In December, after harvesting the plum fruits, Z. jujuba trees are pruned. In January young shoots come up. The brood sticks are tied adjacent to the growing tender branches in the way described earlier. Within a week or two the larvae settle down. Through out the period (February-June) the lac insects secrete a resinous crust on them. In July they are harvested. The branches of Z. jujuba trees are cut into smaller pieces (2 to 4 feet) and tied in bundles. The encrusted lac is then scrapped off the stick and processed in order to get the crude lac.

In the late sixties a Lac Culture Centre was established in Nawabganj which is now almost non-functional. Obviously the lac cultivation is also reduced to its lowest ebb. Most of the locally available lac is of Indian origin. Generally the crude lac is imported, and those locally produced, are extracted in Rajshahi.           –  [Md. Mahtab Ali]

Production of lac – sticky, resinous secretion of the tiny lac insect, Laccifer lacca, which is a species of scale insect. This insect deposits lac on the twigs and young branches of several varieties of soapberry and acacia trees and particularly on the sacred fig, Ficus religiosa, in India, Thailand, Myanmar (Burma), and elsewhere in Southeast Asia.

Production of shellac – commercial resin marketed in the form of amber flakes, made from the secretions of the lac insect, a tiny scale insect, Laccifer lacca (see lac). Shellac is a natural thermoplastic; that is, a material that is soft and flows under pressure when heated but becomes rigid at room temperature. This property makes it useful either by itself or in combination with fillers.