Identification and genetic assessment of transgressive segregants for yield and its contributing traits in wheat (Triticum aestivum L.)

Abstract

Two crosses viz., K 1006 x LOK 1 and PBW 343 x HUW 234 derived from four diverse parents were examined during Rabi 2018-19 and 2019-20 at Agricultural Research Farm, Institute of Agricultural Sciences, BHU in order to identify and assess the robust transgressive segregants (TS) in the segregating F2 and F3 population for yield/plant and its contributing traits respectively. Findings reveal that individuals transgressed beyond the parents in both the crosses for grain yield/plant (9 to 9.52 %). The maximum frequency of TS are found for AL (74.29%) in the PBW 343 x HUW 234 and it was higher for 1000 grain weight (72%) in the K 1006 x LOK 1 cross. The highest number of simultaneous TS for grain yield/plant was found in the F2 for the PBW 343 x HUW 234 (89.5%) followed by K 1006 x LOK 1 (79.0%). The frequency of simultaneous transgression for grain yield coupled with SLPS, GPS, 1000 GW in K 1006 x LOK 1 cross along with NET and AL in PBW 343 x HUW 234 cross was found very frequently. Hence, it is presumed that either grain yield is dependent on these traits or there may be linkage drag among the genes for such traits so that responsible gene(s) could be inherited together. The most promising TS tagged in F2’s were plant No. 36 in the K 1006 x LOK 1 and plant No. 30, 68 and 100 in the other cross. Based on high frequency of TS, it is inferred that transgressive breeding could be used as an excellent tool to improve the crop yield and other desirable traits by recovering the transgressive segregants.