فریبا سهرابی

High temperatures during flowering and grain filling an important factor reducing wheat yields in many parts of the world, including Iran's southern regions respectively. In order to investigate the moderating role of salicylic acid in controlling the negative effects of heat stress on yield, yield components as well as some Morpho- phenological characteristics of wheat, two factorial experiments in 1393 in both normal conditions and heat stress consists of four wheat cultivars Chamran, Kuhdasht , Durum and Dehdasht and different levels of salicylic acid (zero, half and one mM) in a randomized complete block design management research training in the field of Agriculture was jam city. Morpho-phenological traits, leaf proline and total protein were measured. Normality of the data was analyzed. The combined analysis was performed in order to investigate the homogeneity of Bartlett's test pilot errors. Outcome of this experiment showed that heat stress caused a significant decrease phenological traits including days to germination (34%), days to pollination (23%), the number of days to maturity (20%), changes in the morphological characteristics, including reduced plant height (9%), peduncle length (6%), biomass (11%) and grain yield related traits such as ear length (3%), the number of florets (11 percent), the number of tillers (15%) and non-fertile (33%), number of grains per spike (23 percent), grain weight per ear and thousand kernel weight (8%), HI (7%) and yield (16%), respectively. Effect of salicylic acid 5% level was significant in reducing the number of florets (5%), tiller (40 percent), grain yield under normal conditions (6%) and an increase in stress conditions was a day-to-maturity. Therefore, the figure for direct planting in warm areas or use in breeding program to increase heat tolerance is recommended