INHERITANCE OF RESISTANCE TO BROWN PLANTHOPPER (NILAPARVATA-LUGENS) IN RICE

An experiment was conducted to study the inheritance of resistance to brown planthopper (Nilaparvata lugens Stal) in 15 resistant varieties ('BG 379-4', 'IET 7944', 'IET 7946', 'BG 379-1', 'PTB 33', 'IR 19660-2 74-3-3-1', 'IR 17488-2-3-2', 'CR 57 MR 1523', 'Babawee', 'CR 266-407-6 -1'. 'MTU 5295', 'Rathu Heenati', 'MTU 5195', 'RP 2075-5-7-32' and 'IE T 7947') of rice (Oryza sativa L.). These resistant varieties were cro ssed with the susceptible varieties ('TN 1', 'Jaya', 'Mahsuri' and 'BD 202'). The F-1, F-2, F-3 and backcross generations were developed and tested for their reaction to populations of brown planthopper (BPH) f ound at Ranchi. The resistance to the hopper was found governed by a s ingle dominant gene (3:1) in 'BG 379-4', 'IET 7944', 'IET 7946' and 'B G 379-1'; a single recessive gene (1:3) in 'MTU 5195' and 'RP 2075-5-7 -32'; 3 dominant genes (63:1) in 'P TB 33' and 'IR 1960-274-3-3-1'; 2 dominant complementary genes (9:7) in 'IR 17488-23-2' and 'CR 57 MR 15 23'; by inhibitory genes (13:3) in 'Babawee' and 'CR 266-407-6-1; dupl icate dominant genes (15:1) in 'MTU 5295' and 'Rathu Heenati'; and 3 d ominant complementary genes (27:37) in 'IET 7947'. These resistant lin es have diverse sources of resistance to brown planthopper. Hence the allelic genes may be traced in these lines.