Estimate the terminal drought tolerance indices in cultivars and promising lines of bread wheat in Ardabil

In order to evaluate end of season’s drought resistance indices in promising lines of Wheat in Ardabil, twenty promising varieties and promising lines of Wheat were evaluated in randomized complete block design with three replications in two conditions at the Agricultural and natural resources research station Ardebil (alaruq) in 2011-2012. In the first experiment, the irrigation of wheat cultivars as usual continued to achieve physiological stage. But In the second experiment, from Panicle emergence stages in wheat cultivars and lines, irrigation was discontinued. Results showed that, in normal circumstances, between the lines and cultivars for most traits except the number of tillers, grain weight and total Seed weight per plant, straw and total plant weight was significant. In the Terminal drought conditions between the lines and cultivars, except for tiller number, harvest index and days to heading, there was a significant difference. In the normal conditions, Line No. 3 with 8.139 tons per hectare and cultivars, the highest and line number 12 with 5.945 ton/ha were produced lowest yield compared to the other lines. In the normal conditions, the correlation of seed yield with grain weight per panicle and panicle length 0.545 and 0.430, respectively, were positive and significant. In the terminal drought conditions, the Line No. 7 with 5.528 tons per hectare yield was one of the top lines. Estimation of drought tolerance indices for the varieties and lines tested showed that TOL index for lines of 12, 5, 11, and Mihan variety (No. 2), respectively, 1.51, 1.63, 1.91 and 1.87, were most tolerant lines under drought stress after pollination. In terms of index SSI, lines number 12, 5, 7, 11 and figure homeland with their respective index values equal to 0.81, 0.78, 0.83 0.91 and 0.86 were the most tolerant lines under drought stress after pollination of wheat in this investigation Recommend the addition of STI, K2STI and K1STI indicators in lines of wheat selection under normal and drought conditions should be used. Using this indicator, line of Number 7 and Number 10, they were the best treatments of the experiment.