1Department of Agricultural Entomology, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu-641003, India
2Tamil Nadu Rice Research Institute, Aduthurai, -612101
3Department of Plant Biotechnology, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu-641003, India
*Email: anitavsable@gmail.com
Online published on 31 December, 2014.
The present investigations were undertaken to study antixenosis resistance in selected rice genotypes against brown planthopper (BPH) Nilaparvata lugens(Stal). Settling and egg laying behavior of BPH on selected genotypes along with susceptible and resistant checks was studied. BPH nymphs did not show variation in settling preference at 2 hours after release (HAI). At 72 HAI, number of nymphs settled per plant on selected genotypes ranged from 17.10 to 22.10 and TN1 recorded the highest (32.40). Variation in settling preference was more apparent at 24 HAI. Adults showed strong variation in settling preference at all intervals studied. On resistant genotypes insect population reduced over the time whereas it increased on susceptible check TN1. At 72 HAI, the lowest number of adults settled on IR 64 (0.23/plant) and the highest on TN1 (6.15/plant). BPH showed strong nonpreference for oviposition on selected genotypes. Lowest number of eggs was laid on IR 64(19.50/plant) and the highest on TN1 (301.00/plant). Settling and ovipositional non-preference of BPH towards the test genotypes indicated strong antixenosis mechanism of resistance in these genotypes.
Oryza sativa, Nilaparvata lugens, antixenosis, settling, ovipositional preference
