GENETICS OF RESISTANCE TO WHITEBACKED PLANTHOPPER IN FIVE RICE STOCKS

摘要

Five resistant rice stocks, namely, Mudgo, MR1523, ARC11367, NCS2041 and MOI, were crossed with Taichung Native 1 (TNI), a susceptible cultivar, and intercrossed among themselves to study the inheritance of resistance to whitebacked planthopper (WBPH), Sogatella furcifera (Horvath) and the allelic relationships among their Wbph resistance genes. The reaction of F_1, and segregation pattern for resistance in the F_2 and F_3 generations from the crosses of resistant stocks with TNI revealed that a recessive gene conferred resistance in MR1523 and ARC11367 each, whereas, resistance in NCS2041 was conditioned by a dominant gene. The resistance in Mudgo and MO1 was governed by two independently inherited dominant genes. The segregation for susceptible plants in the F_2 generation from the intercross of resistant stocks revealed that the resistance genes in all the stocks are non-allelic to each other except that out of the two dominant genes of MO1, one is allelic to a gene in NCS2041. Based on these results, five new genes for resistance to WBPH have been identified and temporarily designated as WbphMl, WbphMl, wbphAR, WbphN, and WbphO.