Exogenous DCPTA ameliorates the soil drought effect on nitrogen metabolism in maize during the pre-female inflorescence emergence stage

摘要: 2-(3,4-Dichlorophenoxy) triethylamine (DCPTA) regulates many aspects of plant development; however, its effects on soil drought tolerance are unknown. We pre-treated maize (Zea mays L.) by foliar application DCPTA and subsequently exposed the plants to rewatering conditions during pre-female inflorescence emergence stage. Exogenous significantly alleviated drought-induced decreases in yield, shoot root relative growth rate (RGR), leaf water content (RLWC), net photosynthetic (Pn), stomatal conductance (Gs) transpiration (Tr), nitrate (NO3-), nitrite (NO2-), soluble protein contents, reductase (NR), (NiR), isocitrate dehydrogenase (ICDH), alanine aminotransferase (AlaAT) aspartate (AspAT) activities; increases intercellular CO2 concentration (Ci), ammonium (NH4+) free amino acid glutamate (GDH) protease activities. Simultaneously, exogenous improved spatial temporal distribution roots increased hydraulic conductivity (Lp), flow root-bleeding sap NO3- delivery rates. Moreover, protected chloroplast structure from injury. Taken together, our results suggest that mitigates repressive N metabolism enhances stage maize.