Drought Tolerance Evaluation in Maize Germplasms: A Field Study.

Drought stress severely limits plant productivity and causes extensive economic loss to US agriculture. Understanding drought tolerance mechanisms in crop plants is crucial to alleviate the negative impact of drought stress on plant growth and development, especially on the reproduction tissues and crop yield. Maize inbred lines vary greatly in drought tolerance. To study the mechanisms contributing to drought tolerance in maize, eight maize inbred lines that vary in their drought tolerance levels were selected to conduct detailed physiological, biochemical, and genetic analyses at three irrigation levels. Parameters of water potential and photosynthesis were measured at different stages of drought treatments. Leaf samples were collected for metabolic measurement. Gene expression profiles are being conducted for selected inbred lines. The long term goal for this study is to identify drought tolerance mechanisms in maize, generate mapping population, identify major QTLs associated with drought tolerance, and select molecular markers for marker-assisted-selection of drought tolerant varieties in maize breeding program.