Bionomics of slender burnished brass (Thysanoplusia orichalcea [Fabricius, 1775], Lepidoptera: Noctuidae) on potato (Solanum tuberosum L.) in Kashmir

Abstract

A study on biology, morphometrics and geometrical progression of Thysanoplusia orichalcea was conducted on Solanum tuberosumunder laboratory conditions. Different stages viz., egg, larva, pupa and adult of T. orichalcea were observed for their duration and morphometric measurements. The pest depicted five larval instars and moultedfour times during the entire period. The average pre oviposition and oviposition period was observed to be 3.80 and 2.80 days respectively.Further, fecundity ranges between 381.0-400.0 with an average of 388.0 eggs. The mean incubation period was found to be 4.2 days. The average larval, pre pupal and pupal period was completed in 23.1, 1.4 and 9.5 days respectively. While mean adult longevity on S. tuberosum was 7.45 days. The total life cycle was completed in 41.0-51.0 days with an average of 45.65 days. Moreover, mean head capsule width of first, second, third, fourth and fifth larval instar was found to be 0.33, 0.54, 0.88, 1.46 and 2.24 mm respectivelywith Dyar’s ratio/ growth ratio of 1.63 mm. The expected head capsule width of first, second, third, fourth and fifth larval instar wasobserved as 0.33, 0.53, 0.86, 1.40 and 2.28 mm respectively.