Abstract:

Drought is one of the important factors affecting the yield stability of maize (Zea mays L.) in China and some other areas in the world. In order to provide materials and academic basis for maize drought resistance breeding, 84 elite main inbred lines were grown at Hainan and Gansu provinces in China in 2002 and 2003. Two levels of drought treatment were imposed, well-watered and water-stressed. Experiments were arranged in a complete random block design with three replications. Each genotype was grown in one row of 10 plants, 3 m long and 0.67 m apart. The drought resistance of the materials was evaluated according to drought coefficient and drought index. Based on the drought coefficient, 12 genotypes, S22, Zheng 22, Shen 5003, K10, Longkang 11, Hai 014, Chang 3, Ji 853, Shuang 741, Danhuang 02, Xi 502 and D978 were with high drought resistance; 15 genotypes, Ye 478, Ben 7884, Ye 8112, Dong 237, Tian 77, B73, Chang 72, Hai 1134, Wu 109, Yan 812, Nan 21-3, Q1261, Mo 113, Luyuan 92 and D892 were with medium drought resistance. Based on the drought index, eight genotypes, Zheng 22, K10, Chang 3, Ye 8001, Danhuang 02, K22, Xi 502 and D978 were with high drought resistance and high yield; 17 genotypes, Ye 478, Ji 444, Ben 7884, Huangyesi 3, Cheng 200B, Qi 319, Za C546, Tian 77, B73, Tie 7922, Chang 72, Dan 9064, Wu 109, Yan 812, K14, Ye 5237 and D863 were with medium drought resistance and high yield. The results showed that there existed inbred lines with different types of drought resistance and of high yield and drought resistance, which were the important germplasms for drought resistant breeding in China. Among the inbred lines some showed drought resistance in both middle and later period of growth, some only in one period. The high yield with high drought resistance was realized through different ways, some through higher index of kernel number and 100-kernel weight, some through higher index of kernel number and others through higher index of 100-kernel weight. It is possible to get elite cultivars with both high yield and high drought resistance by using different inbred lines above in the breeding for drought resistance.

Key words: Zea mays L., Inbred lines, Drought resistance