Broodlac and sticklac yield as affected by site of inoculation, shoot length coverage and irrigation levels

Abstract

Flemingia semialata is an important bushy lac-host plant which is utilised, in alteration with other lac-hosts for lac cultivation during rainy season. However, plant and lac insect mortality due to stress of heavy inoculation and lack of irrigation is a common problem in bushy lac-hosts which not only adversely affects the production of raw lac but also the quality of broodlac. Studies on effect of site of inoculation, percentage shoot length coverage and different levels of irrigation revealed that all the plants inoculated at lower part and 57.2% of the plants inoculated at upper part did not yield lac and the middle portion of one year old stalk was preferred by the lac nsect for settlement. Average broodlac (63.5 g) and sticklac (33.0 g) yield was maximum in the middle inoculated plant. 40% coverage of inoculable shoot length gave maximum returns for broodlac cultivation, through, sticklac yield increased with increase in shoot coverage up to 80%. Irrigation of crop at regular intervals improved the quality of the broodlac. Number of lac larvae emerging from 10 g of broodlac cultured on daily irrigated plants covered 91.8 cm shoot in comparision to 35.4 cm covered by lac larvae emerging from broodlac obtained from un-irrigated plants. Survival of female lac insects till crop maturity also increased from 23.1% in control to 65.5% in daily irrigated plants.