Determination of transpiration efficiency effects on drought and yield relationships at durum wheat (Triticum turgidum L.var. durum)

This study was carried out to determine the response of drought stress for early and late flowering wheats in which grow genotypes in semi controlled greenhouse of Dicle Ünivesity Agricultural Faculty, Diyarbakır, Turkey. In this study, the methods of exposing dry down and vapour pressure difference (VPD) methods were used to measure transpiration related traite. An additional group of the genotypes was performed to measure the yield of all the genotypes. The transpiration breaking point which determined by FTSW and NTR values estimated under increasing drouht stress. The highest transpiration breaking point was obtained at Tbt16-9 and Kunduru 1149 genotype For that, these genotypes saved more water in the soil under the stress conditions. Transpiration from the plants increased as long as VPD increased. The elevated transpiration of the genotypes in raising BBF conditions where soil water is not restricted is advantageous for cooling themselves. The highest transpiration in rising BBF was optained the Svevo and Bağacak of early flowering genotypes under greenhouse and controlled condition, while late flowering of Kunduru 1149 had highest transpiration rates at both conditions. Fırat-93 and Hacımestan were the best performing genotypes at the normal conditions. It could be stated that the genotypes of Çeşit-1252 and Tbt16-9 were more resistant to drought considening FTSW and VPD.