1Department of Agril. Entomology, T.N.A.U., Coimbatore 641 003, India.
2Diviston of Entomology, I.A.R.I., New Delhi 110 012, India.
The levels of mechanism of resistance viz., antixenosis and antibiosis against Nilaparvata lugens was studied in rice genotypes including 5 rice hybrids namely CORH2 (IR 58025A/C20R), IR 58025A (IR4843A/PUSA 167-120-3-28), C20R, CIO, IET 15423, TNI, PTB33 and IR54742-22-19-3R. The levels of resistance were found to be varying in different resistance parameters in the tested genotypes. However, comparatively less nymphal preference, fecundity and hatchability, increased nymphal duration, adult longevity less honey dew excretion, more feeding marks and reduction life span were recorded in all resistant genotypes than the susceptible T(N)1.
Oryza sativa, Nilaparvata lugens, Resistance mechanism
