author(s)
Praveen Kumar, SP Yadav, Krishna Rolania and Puneet

abstract
Biology of Amrasca devastans (Ishida) on transgenic cotton hybrid, RCH 650 BGII and desi cotton hybrid, AAH 1 cotton was studied in the laboratory of Department of Entomology, CCSHAU, Hisar. The average total nymphal period on RCH 650 BGII (transgenic cotton) lasted for 6.50 ± 0.55 days whereas, it lasted for 7.67 ± 0.52 days on AAH -1 (desi cotton hybrid). The nymphal survival on RCH 650 BGII ranged from 40 to 70 per cent with an average of 56.67 ± 10.33 per cent while it ranged from 30 to 50 per cent with an average of 43.33 ± 8.16 on AAH -1. Nymphal growth index was 8.72 for RCH 650 BGII and 5.65 for AAH 1. Sex ratio of male: female was 1: 0.84 and 1: 0.82 on RCH 650 BGII and AAH 1, respectively. Maximum number of eggs per leaf i.e. 35.20 ± 3.91and 29.60 ± 3.78 were found on August 7, 2016 (32nd SMW) on RCH 650 BGII and AAH 1, respectively. The maximum average number of eggs in lateral veins were 16.9 ± 3.51 and 12.5 ± 2.46 on RCH 650 BGII and AAH 1, respectively. On August 22, 2016, in lateral veins of RCH 650 BGII had 13.6 ± 2.37 eggs and AAH 1 had 7.5 ± 2.12 eggs which were maximum among other veins. On September 6, 2016 (34th SMW), maximum average numbers of eggs in sub veins had 6.1 ± 1.79 and 3.7 ± 1.34 number of eggs in RCH 650 BGII and AAH 1, respectively.