Drought tolerance evaluation of new maize hybrid combinations in the oasis irrigation areas

Objective To screen out the new hybrid combinations of maize with high yield and strong drought resistance.

Methods The drought resistance of 76 maize hybrid combinations was evaluated by the weighted drought resistance coefficient method, and the yield was analyzed.

Results Compared with normal irrigation treatment, the different character indexes of 76 maize hybrid combinations showed a decreasing trend after drought stress, and the decrease was between 2.61% and 31.21%. The yield decreased by 35.39% and ASI increased by 0.27 d. Six traits including plant height, row number per ear, ear length, ear diameter, ear weight and grain weight were selected for comprehensive evaluation of drought resistance in this study. The weighted drought resistance coefficients of 76 hybrid combinations ranged from 0.6764 to 1.0418, among which 9 combinations were grade 1 drought resistance, 10 combinations were grade 2 drought resistance, 36 combinations were grade 3 drought resistance, 11 combinations were grade 4 drought resistance and 10 combinations were grade 5 drought resistance. After drought stress, the yield of 22FP146, 22FP221, 22FP037 and LD888 hybrid combinations were 16546.66, 16168.00, 15289.43 and 15152.37 kg/hm², respectively. Compared with the normal irrigation treatment, they decreased by 8.93%, 13.02%, 30.48% and 15.79%, respectively, and showed strong drought resistance.

Conclusion Four hybrid combinations of 22FP146 (Ludan 9226), 22FP221 (7854×lx209), 22FP037 (9258×lx206) and LD888 (Ludan 888) with high yield potential and strong drought resistance were selected, which could be promoted in arid and semi-arid areas and water-saving agricultural areas with similar conditions as Hexi Oasis irrigation areas in Gansu Province.