Selection of drought resistant materials and drought resistant index for maize in South China

Drought climate (July to August) in southern China poses tremendous threat to maize production. In this paper, drought-resistance characteristics and indexes of 12 maize inbred lines were investigated by water weight control method at seedling stage, and equivalent water supply at booting to filling stage of maize. The results show that “178” is the most drought-resistant inbred line at seedling and booting to filling stages, while “Qi319” and “S4084” are the drought-sensitive inbred lines at seedling and booting to filling stages. For drought-sensitive materials, 7 days is the longest drought duration at seedling stage， and for drought-resistant materials, 12 days is the longest duration. Seedling survival rate can be used as drought-evaluation index while photosynthetic rate and the difference between pre- and post-treatments of relative electric conductivity as well as proline and soluble sugar contents can be handy and reliable drought-evaluation index.