Differential response of F4 and F5 green gram [Vigna radiata (L.) Wilczek] recombinant inbred lines (RILs) to powdery mildew infection

Abstract

Green gram is severely affected by powdery mildew caused by fungus Erysiphe polygoni D.C. The present investigation involved F4 and F5 generations of RILs of two crosses viz., Chinamung × BL-849 and Chinamung × LM-1668 which has contrasting response for powdery mildew resistance with 146 and 155 lines respectively. Out of 146 F4 RILs screened in cross Chinamung × BL-849, one of them was found to be highly resistant (R0) viz., C1-34-23. When screened in Rabi season (F5) showed fourteen RILs to be R0. Whereas in cross Chinamung × LM-1668 155 F4 RILs screened, thirty nine RILs were found to be moderately resistant (R2) whereas in Rabi season (F5) showed one hundred and four R2.Similar resistance response by the lines like C1-34-23 in cross Chinamung × BL-849 and C2-14-11, C2-16-13 RILs in cross Chinamung × LM-1668 in both seasons clearly indicates that these lines have become stable for the disease response. Such lines can be screened for yield related traits to develop highly resistant breeding lines with high yielding ability in green gram.