MARKER ANALYSIS AND FIELD SCREENING STUDIES IN RICEFOR BLAST RESISTANCE

摘要

Rice improvement for durable resistance to blast is difficult due to its complexity. Rice blast, caused by fungus Magnaporthegrisea, is a serious disease causing considerable economic damage worldwide. Blast is one of the destructive diseases, which causes maximum yield losses in rice. Best way to overcome the disease is to breed for disease resistant cultivars/parental lines of hybrids. The present study was conducted to analyse blast resistance in rice. Rice genotypes viz./VRPl, VRP2, B95-1 X Tetep, BPT5204 X Tetep, C039 and C043 were screened for blast resistance in artificial condition. The study indicated that the genes Pi9 and Pi54 recorded resistance reaction to blast pathogen occurring in Tamil Nadu. The blast resistant gene, Pi9 is presentin VRP1 and VRP2 and another blast resistant gene Pi54 is present in the derivatives of B95-IX Tetep and BPT5204 X Tetep. Tightly linked markers NBS4 and Pi54-MAS were already identified for the genes Pi9 and Pi54 respectively. The present study indicated that the tightly linked markers showed polymorphism between resistance and susceptible rice genotypes indicating the possibility of initiating MAS for blast resistance in rice.