Genetic Validation of Promising Warangal Rice Cultures for Gall Midge Resistance Using Functional Markers

Abstract

The experiment was conducted during Rabi 2023-24 at Regional Agricultural Research Station, Warangal. The Asian gall midge Orseolia oryzae is one of the major pests of rice which is causing significant economic loss to the crop. Thirty nine rice cultures along with resistant checks (Aganni and RMSGM3) and susceptible check (TN-1) were screened for the presence of three gall midge resistance genes namely, gm3, Gm4 and Gm8 by using functional markers like gm3del3, LRR-del and PRP, respectively. Out of 37 rice cultures, seven rice cultures namely, WGL-1940, WGL-1942, WGL-1956, WGL-1963, WGL-1145, BM-71 and WGL-2039 were observed to be triple positives by possessing all the three gall midge resistant genes (i,e. gm3, Gm4 and Gm8), While three rice cultures namely, WGL-1778, WGL-1964 and WGL-1800 were observed to posses gm3 and Gm8 gall midge resistance genes and 9 rice cultures namely, WGL-1781, WGL-2000, WGL-1941, WGL-1960, WGL-2038, WGL-1127, INRC-3021 and WGL-1121 were observed to posses Gm4 and Gm8 genes. One rice culture i.e., RP2068-18-3-5 was observed to be double positive for gm3 and Gm4 genes. This research successfully identified gall midge resistance genes in 73% of the rice cultures tested using functional markers. These results will aid in the creation of new rice varieties resistant to gall midge, enhancing crop yields and food security in impacted areas. Some of the promising rice cultures may be utilized as donors in breeding programs for development of pyramided lines with durable gall midge resistance.