Rice Brown Planthopper, Nilaparvata lugens (Stål) Feeding Behaviour in Resistant NAGINA22 Rice Mutants

Abstract

Background: Rice (Oryza sativa L.), is an important staple food and an excellent source of calories in India. Of the different insect pests attacking rice, brown planthopper, BPH, Nilaparvata lugens (Stål) is an important sucking pest causing upto 100% yield losses. Host plant resistance is the most important method in keeping BPH under control and understanding the underlying mechanisms of resistance is necessary to breed the resistant varieties with desirable characters. Methods: Selected EMS mutant lines of Nagina22 (N22) variety, which were previously mass screened under controlled greenhouse conditions were assessed for their antixenosis mechanism to brown planthopper feeding by measuring probing marks and honeydew excretion area by following standard procedures and statistical analysis was done by using Statistix 8.1 software. Result: Both the brown planthopper nymphs and adults probed more in the resistant mutants compared to the susceptible mutants whereas the BPH adults probed more times (24.4) compared to the nymphs (22.2). The recorded honeydew excretion area by the resistant mutants was lower than that of susceptible mutants. In general, the BPH adults fed more and excreted more honeydew (79.5 mm2) compared to the nymphs (59.0 mm2). The damage score has a negative correlation with the probing marks of adults (-0.207) and nymphs (-0.411); and a positive correlation with honeydew excretion of adults (0.547) and nymphs (0.200). In this study, the EMS N22 mutants resistant to BPH, with a greater number of probing marks and less honeydew excretion area can serve as best donors in the breeding programmes to develop brown planthopper resistant varieties.