Analysis of Drought Tolerance of Sixty-nine Maize Inbred Lines at Seeding Stage

Sixty-nine maize inbred lines were cultivated under simulated drought-stressed condition in greenhouse.Five physiological and biochemical indexes of these inbred lines were tested,which included SOD activity,MDA content,proline content,relative conductivity and relative water content.Two morphologic indexes were tested,which included stem diameter and root-shoot ratio.Based on the Fuzzy Clustering of five physiological and biochemical indexes,drought tolerance of the inbred lines was evaluated.And the correlation between comprehensive evaluation and morphologic indexes in lab were analyzed.The main results were summarized as follows:(1) under drought-stressed condition,the classification of the inbred lines was different and the response mechanism was different.(2) 4 inbred lines with high drought tolerance,14 inbred lines with drought tolerance,35 inbred lines with medium drought tolerance,12 inbred lines with drought susceptible,4 inbred lines with high drought susceptible were screened.(3) Because the correlation between comprehensive evaluation and morphologic indexes was very low,stem diameter and root-shoot ratio were unfit to identify drought tolerance in lab.