Screening of high volume breeding lines of hexaploid wheat for drought tolerance usii cluster analysis based on kernel yield and STI.

摘要

Late season drought stress either due to high temperature or shortage of water in irrigated wheat farms causes a significant reduction in quantity and quaUty of kemel yield in Iran. In order to find wheat varieties tolerant to late season shortage ofwater; this study was done in breeding program of temperate region. In this study 280 advanced breeding lines of hexaploid wheat were planted in two field trials; one under normal irrigation and another one stressed for that. The normal trial received6 times fiirrow irrigation from May 3 until June 21; 2002 while the water stressed trial received only one irrigation in Spring at anthesis stage. Drought resistance indices including SSI; TOL; MP; STI and GMP were calculated for all investigated entries. Using cluster analysis based on normal yield; stressed yield and STI; approximately four genotype groups A; B; C and D were determined. With this method we selected 51 promising breeding lines to be evaluated in multilocation tests in next season. We also found STI and GMP as the better indices than other three for screening of drought tolerant wheat varieties.