Reaction of Rice genotypes against specific population of brown planthopper, Nilaparvata lugens (stål)

Mass screening of twenty six selected rice genotypes along with resistant and susceptible checks viz., Ptb-33 and TN-1 were screened using standard seed box screening technique (SSST) and modified seed box screening technique (MSST) to evaluate the BPH resistance against the local population (Coimbatore, India) of BPH (Nilaparvata lugens) in glass house condition. Among the 26 rice genotypes screened none of the entry was observed as highly resistant in both the methods. In SSST method, RP 2068-18-3-5 and ASD-7 were found to be resistant with the mean score between 2.25 and 2.85. Ptb-41, T-12, Rathuheenathi, Swarnalatha, Ptb-19, Pokkali, Chinsaba, Mudgo and Vellaikudavazhai were found to be moderately resistant. In the MSST 12 genotypes viz., Ptb-41, T-12, Ptb-19, RP 2068-18-3-5, ADT-36, Rathuheenathi, Vellaikudavazhai, ASD-7, Mapillai Samba, Chinsaba, IR 65482-7-218-1-2-B and IR-64 were found to be moderately resistant while remaining cultures were either susceptible or moderately susceptible in both techniques. The entries Rathuheenathi, Ptb-33 which possessed Bph 3 gene and T-12 which had bph 7 gene recorded resistant/moderately resistant reaction in both the mass screening methods. However, the other entries Swarnalatha (Bph 6), Chinsaba (bph 8), Pokkali (Bph 9) observed as moderately resistant in SSST and moderately susceptible in MSST. The entry Babawee which had Bph 4 gene showed susceptible reaction in both the methods for the BPH population.