IDENTIFICATION OF RESISTANT RICE GENOTYPES AGAINST BROWN PLANTHOPPER, NILAPARVATA LUGENS STAL (HOMOPTERA: DELPHACIDAE)

摘要

In rice production there are many constraints, of which insect pests remain a constant problem in all the rice growing regions (Manikandan et al., 2014). Brown planthopper (BPH), Nilaparvata lug ens (Homoptera: Delphacidae) is one of the most destructive insect pests. It is also a vector, transmitting viral diseases such as grassy stunt, rugged stunt and associated diseases (Khush et al., 1985). Regular insecticide spraying under intensive farming practices to control BPH had resulted in the loss ofnatural predators and the selection of pesticide resistant biotypes, resulting in BPH resurgence (Whitten and Oakeshott, 1991; Hadfield, 1993). Although BPH resistant varieties were identified from the germplasm collection, resistant breaking biotypes rapidly overcome resistance mechanisms introduced by conventional breeding (Senguttuvan et al., 1991; Gallagher et al., 1994). As a component of IPM strategies for rice, new resistant varieties are required. The use of resistant varieties is the most economical and efficient method for controlling the BPH, hence the present study to identify the sources of resistance.