IDENTIFICATION AND INTROGRESSION OF BPH3 RESISTANCE GENE INTO RICE ELITE LINES

Rice is a staple crop grown in the world, providing food for more than half of the population. Hybrid rice is a useful method for increasing rice yield. Many diseases and insects attack the rice plant. Among the insect pests, planthoppers cause significant yield losses. Brown planthopper (BPH) is a typical vascular feeder and one of the most serious and destructive rice pests that can be found throughout the rice-growing area. It causes severe yield reduction by directly sucking the plant sap and acting as a vector of various viral diseases such as rice grassy stunt virus (RGSV) and rice ragged stunt virus (RRSV). Heavy infestations cause complete drying and plant death, a condition is known as hopper burn. The deployment of host resistance has been recognized as one of the most economical and effective methods for Brown planthopper (BPH) management. Many donors of Brown planthopper (BPH) resistance have been identified and genetic characterization of the resistance has been investigated. To date, more than 38 major Brown planthoppers (BPH) resistance genes have been reported in several Oryza sativa sps. indica cultivars and wild relatives. Two near-isogenic lines (NILs) with introgression Bph3 from Vellathu cheera (IRGC54827) trough marker-assisted breeding (MAB) and Bioassays method. RM589 SSR (simple sequence repeats) marker is linked to the Bph3 resistance gene, which is used for genotype screening the populations. Biotypes 4 insects were used for phenotypic screening. Phenotype screening showed that the improved near-isogenic lines (NILs) and their derived hybrids carrying Bph3 gene were resistant to Brown planthopper (BPH), the improved hybrids showed superior agronomic performance. Vellathu cheera donor line contains Bph3 gene, it gives more resistance for Brown planthopper (BPH) this study demonstrates that it is essential to Introgres the BPH3 gene into hybrid parental lines for developing Brown planthopper (BPH) resistant hybrid.