Molecular mapping of transpiration-leaf temperature relations in maize under drought conditions

The need for the development of the water use efficient cultivars for the crops consuming too much water such as maize has emerged as a result of global warming and decreasing water resources. This research aimed to investigate the responses of maize plant (Zea mays L.) to water stress in terms of leaf temperature and some other traits and to determine the genomic regions controlling the measured traits. The research was conducted at 2016, 2017 and 2018 maize growing seasons under İzmir Bornova ecological conditions. In the first year of the research, 80 different maize inbred lines were cultivated in augmented block design. Canopy temperature depression (CTD), chlorophyll content (SPAD), leaf relative water content (LRWC), single plant yield and thousand grain weight (TGW) traits were measured under control and water stress treatments. Besides, two inbred lines Ames26783 and NSL30869 which were determined as the contrasting genotypes in terms of CTD trait were crossed. The F1 generation was grown under field conditions in the second year of the research. F2 individual plants were grown under field conditions in the third year of the study. Pre anthesis water stress treatment was applied to the F2 population. CTD, SPAD, plant height, leaf number, first cob height, TGW and plant yield traits were measured on F2 individual plants and population was genotyped with the SSR markers. According to the results, water stress affected the CTD and SPAD traits significantly. Also the SSR marker umc1165 was found highly related with the CTD trait in F2 population under water stress. Additionally, the SSR markers related with plant height, first cob height, leaf number, TGW and SPAD were determined.