1Division of Lac Processing and Product Development, Indian Lac Research Institute, Namkum, Ranchi-834 010, Bihar (India).
2Indian Agricultural Statistics Research Institute, Library Avenue, New Delhi-110 012 (India).
To identify the important yield affecting attributes in lac for summer season crop of rangeeni lac on Butea monosperma (Lam.) Taub., 14 factors were studied. Significant and positive correlation was found with yield and quantity of broodlac used for raising lac insect culture, number of host shoots with lac culture, height of host crown, length of lac insect settlement per shoot, volume occupied by hundred female lac insects, diameter of host canopy and number of stumps per tree in decreasing order of magnitude. The forecast model, retaining quantity of broodlac used, number of host shoots with lac culture per tree, length of lac insect settlement per shoot and number of living lac insect per cm2, explained 51 per cent variation in yield. The model developed showed that forecast of sticklac yield per tree is possible once lac insect culture is established on shoots (3–4 weeks after raising the culture). This corresponds to 20–22 weeks before the crop harvesting.
