Evaluation of rice genotypes for rice brown plant hopper resistance through phenotypic reaction and genotypic analysis

Abstract

Fifty eight rice genotypes including 39 landraces from Odisha state, India were phenotyped against a brown plant hopper (BPH) population at the Central Rice Research Institute (CRRI), Cuttack through the modified seed box technique, the nymphal survival test and the nin-hydrin test of feeding. High levels of resistance was found in nine genotypes, namely Baiganamanji, Champa, Assamchudi-K, Akula, Balibhanjana-T, Assamchudi-B, Champeisali-B, Ganjeijata-P and Harishankar-D. Known gene differentials for BPH such as IR 64 (Bph1), IR 36 (bph2), ASD 7 (bph2), Swarnalata (Bph6), T 12 (bph7), Chinsaba (bph8), Pokkali (bph9) and Rathu Heenati (Bph3+Bph17)) included in the study for comparision showed susceptible reactions to the CRRI BPH population. The genotype Babawee (bph4) was moderately resistant whereas three others (Bph18, Bph20/21 and bph2+Bph3) were highly resistant along with previously CRRI- identified donors of BPH such as Salkathi, Dhobnumbari, Jalakanthi and Dhoiya bankoi of CRRI. Genetic diversity analysis of all the genotypes through 22 gene-linked markers of BPH resistance categorized them into 4 major clusters with the 40% level of genetic similarity. The phenotypically highly resistant genotypes were grouped together under the same major cluster I indicating their similar genetic background, but there were other resistant materials which were grouped differently showing their genetic diversity. The resistant genotypes can be utilized as efficient donors for developing rice varieties with resistance to BPH.