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.
Highlights
2 MATERIAL AND METHODSVegetables are indispensable as they make up a major part of the human diet in many parts of the world
Oviposition occurred during night time at 25 oC and 65 % RH and the eggs were laid on lower surface of the leaves of potato The freshly laid eggs of T. orichalcea were green, spherical and shiny
In light of the damage caused by T. orichalcea, the evaluation of its bionomics could be advantageous for the better management of this obnoxious pest
Summary
2 MATERIAL AND METHODSVegetables are indispensable as they make up a major part of the human diet in many parts of the world. It is leading tuber crop all over the globe (Anonymous, 2011a). India generates about 42.34 million tons of potato from 1.86 million hectares of land, positions fourth in terms of area and third in terms of potato production in the entire world (Anonymous, 2011a). Around 34.000 t of potatoes are harvested in Kashmir valley from an area of about 1.7 thousand hectares (Anonymous, 2011b). Despite of the numerous health benefits of potato, its production is still less because of the massive crop damage due to amplified pest menace. Due to the lack of resistant characters because of rigorous hybrid cultivation, vegetables are more prone to insect pests and diseases (Dhandapani et al, 2003)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have