Productivity-linked parameters of the Rangeeni strain Lac Insect, Kerria lacca (Kerr) on Pigeonpea, Cajanus cajan Linn. at Rajasthan
Chetan Kalahal, Hemant Swami and Lekha
The present investigation on productivity-linked parameters of lac insect on pigeonpea was carried out on Rangeeni strain of lac insect in Katki season at lac insect gene bank cum garden situated at Rajasthan College of Agriculture, MPUAT, Udaipur during 2016. The results revealed that the initial density of settlement of first instar crawlers on a plant varied in different parts of plant which ranged from 20-121 crawlers per sq.cm and with a mean initial density of settlement of 92.60, 84.10, 60.00; 86.70, 91.60, 71.00 and 67.40, 64.70, 61.00 crawlers per sq.cm at lower, middle and upper parts of plants in three plots respectively and the per cent mortality ranged from 6.46-12.57 per cent. The mean final density of settlement first instar crawlers ranged from 17-114 crawlers per sq.cm with mean of 85.50, 78.20, 53.10; 80.20, 85.90, 65.00 and 61.90, 57.30, 54.60 crawlers sq.cm on lower, middle and upper portion of plant in three plots respectively. The density of female cells during maturity ranged from 01-11 cells per sq.cm and the fecundity recorded for single female cell was 95-430 larvae per cell. The cell and resin weight ranged from 6-24 mg per cell, 4-19 mg per cell, respectively while mean sticklac and scrappedlac yield recorded were 235 g per plant, 15.63 g per plant respectively.