TRANSCRIPTIONAL ANALYSIS OF MAIZE UNDER DROUGHT STRESS AND THE IMPACT OF PLANT MATURITY

Climate change related drought is projected to harm maize production. Water use strategies can help mitigate the impact of drought on crop yield. However, little is known about maize metabolic response to drought at different developmental stages. To shed light on this, drought conditions were applied to maize at the six-leaf stage (V6), twelve leaf stage (V12), and tassel stage (VT). V6 and VT took eight days to achieve a low stomatal conductance threshold, but V12 took 16 days. Differential gene expression analysis of the transcriptome indicates that V6 showed the most response with 53 impacted metabolic pathways, many of which indicated cellular damage and a reduced stress tolerance. V6 showed water conservation. Twelve and ten pathways were modulated under drought conditions at the V12 and VT stages, respectively. V12 had pathway modulation indicating water conservation and improved stress tolerance. VT responses focused on growth and development, not water conservation.