University of Tehran perss Journal of Crops Improvement 2008-8337 19 3 2017 11 22 Evaluation of sink limitation and assimilates distribution of wheat genotypes under terminal drought stress Evaluation of sink limitation and assimilates distribution of wheat genotypes under terminal drought stress 717 732 60479 10.22059/jci.2017.60479 FA S. Javad Talebzadeh Hashem Hadi Reza Aminia 0000-0002-5865-6243 Mehdi Tajbakhsh 0000-0002-2815-5472 Mohammad Rezaie 0000-0002-3684-2053 Journal Article 2016 11 07 <strong>In order to evaluation the pattern of assimilates distribution to seed under late season drought stress, 11 promising lines of winter wheat along with Orum, Zareh, Mihan, Zarrin and Pishgam cultivars were evaluated in two levels of irrigation (full irrigation and cutting irrigation from flowering to maturity) at the Agricultural Research Station of Miandoab during 2013-2015 growing seasons. Experiments were conducted in </strong>split<strong> plot based on randomized complete block design with three replications. Results showed that water deficit stress significantly increased remobilization rate, contribution of remobilization and source restriction and decreased the amount of spike weight, peduncle weight, sink restriction by removing leaves other than flag leaf, sink restrictions by removing flag leaf, grain yield and harvest index, so that terminal water deficit stress increased remobilization by 45.45% and the total yield contribution of remobilization of 18.30% in normal conditions increased to 43.33% under stress conditions. Among the genotypes, ‘Zarrin’ and ‘Mihan’ under normal moisture conditions and ‘Mihan’ genotype under terminal drought stress conditions produced the highest grain yield. In this study under terminal drought stress conditions, there were significant positive correlations between grain yield with remobilization rate and contribution of remobilization. It can be concluded that the varieties and genotypes afforded adequate remobilization and contribution of remobilization in grain yield in both conditions are appropriate for cultivation in optimal conditions, as well as areas that are faced with terminal water deficit stress.</strong> <strong>In order to evaluation the pattern of assimilates distribution to seed under late season drought stress, 11 promising lines of winter wheat along with Orum, Zareh, Mihan, Zarrin and Pishgam cultivars were evaluated in two levels of irrigation (full irrigation and cutting irrigation from flowering to maturity) at the Agricultural Research Station of Miandoab during 2013-2015 growing seasons. Experiments were conducted in </strong>split<strong> plot based on randomized complete block design with three replications. Results showed that water deficit stress significantly increased remobilization rate, contribution of remobilization and source restriction and decreased the amount of spike weight, peduncle weight, sink restriction by removing leaves other than flag leaf, sink restrictions by removing flag leaf, grain yield and harvest index, so that terminal water deficit stress increased remobilization by 45.45% and the total yield contribution of remobilization of 18.30% in normal conditions increased to 43.33% under stress conditions. Among the genotypes, ‘Zarrin’ and ‘Mihan’ under normal moisture conditions and ‘Mihan’ genotype under terminal drought stress conditions produced the highest grain yield. In this study under terminal drought stress conditions, there were significant positive correlations between grain yield with remobilization rate and contribution of remobilization. It can be concluded that the varieties and genotypes afforded adequate remobilization and contribution of remobilization in grain yield in both conditions are appropriate for cultivation in optimal conditions, as well as areas that are faced with terminal water deficit stress.</strong> https://jci.ut.ac.ir/article_60479_effaf99c8cdbc50bfc4eba7be573bbfb.pdf