Vol. 10, Issue 2, Part B (2024)

Abstract
Mulberry being the sole food for silkworm Bombyx mori L. it is known to be attacked by many insect pests. The major pests of mulberry are Leaf roller, Bihar hairy caterpillar, Cut worm (Lepidoptera), Jassid, Spiralling white fly, Mealybug, Scale insect (Homoptera) (Naik S L., 1997). Among the various pests, the Leaf roller, Diaphania pulverulentalis (Lepidoptera: Pyralidae) causes damage to the mulberry plant by infesting the apical portion and it occupies the key position in reducing the mulberry leaf yield and quality with an average incidence of 27.85% in Karnataka, 20.98% in Andhra Pradesh and 16.48% in Tamil Nadu and the incidence is severe during winter months (October- February) (Geethabai et al., 1999). The leaf roller, D. pulverulentalis (Hampson) (Lepidoptera: Pyralidae) is a major pest of mulberry causes considerable reduction in mulberry leaf yield resulting in economic loss to sericulturists. The incidence of leaf-roller and mulberry leaf yield loss were 70.30 and 25.20 percent, respectively. To understand the duration of life cycle, longevity and fecundity of the insect, newly hatched larvae were separated from the stock culture. Twenty pairs of Mulberry leaf roller adult moths were released into the cage for pairing and egg laying under controlled conditions (26±2 °C and 75 to 80% RH). The investigation was carried out during 2018-21 at the Department of Sericulture UAS, GKVK, Bengaluru-65 and revealed the D. pulverulentalis eggs incubation period was about 2.11 to 4.01 days with a mean of 3.14±0.96 days. The hatching percentages were found to be in the range of 88.07 to 96.03 percent, with a mean of 93.10±4.38 percent. The duration of first, second, third, fourth and fifth instar were 1.54 to 3.47 with the mean of 2.53±0.97 days., 1.84 to 2.74 days with the mean of 1.51±1.07 days, 1.94 to 3.51 days with mean of 2.67±0.79 days, 2.00 to 4.01 days with the mean of 3.19±1.05 days and 3.51 to 5.01 days with a mean of 4.35±0.77 days, respectively. The pupal period was 3.51 to 5.01 days with a mean of 4.35±0.77 days. The adult longevity of male moths in the present study ranged between 3.02to 5.02 days, with a mean longevity of 4.00±1.00 days, whereas that of female moths ranged between 6.32 to 8.44 days with a mean of 7.52±1.1 days. The adult longevity was greater in female moths than that of the male moths. The average fecundity of adult female was 80.02 to 150.12 eggs with an average 108.46±36.87 eggs.