effect of salinity stress on some agronomic characteristics,grain yield and its components in seri/babax recombinant inbred lines wheat

to study and determine  effect of salinity on relationship between  agronomic  characteristics and grain yield, 167  of  the  seri/babax recombinant wheat inbred  lines (ril) together with two parents were evaluated using alpha latice design with two replications under two conditions (salt stress and normal), in zabol field station in 2011-12 cropping season. fourteen  traits  including: some agronomic characteristics, grain  yield  and  its  components,  were  measured  and  recorded  for  169  genotypes. results  of  simple  correlation  coefficient  analysis  indicated  a  significant  positive  correlation  between  grain  yield   with  harvest  index, biological  yield, the  number  of  spike  m-2  and  the  number  of  grain m-2 for both normal and stress conditions. stepwise regression analysis showed that biological yield, harvest index, 1000 grain weight and days to heading were of higher importance, among other grain yield components for normal condition, in determination of grain yield. whereas in stress condition, biological yield, harvest index, plant m2 and plant height were the most important. path analysis coefficients showed that the highest direct effects on grain yield were biological yield and harvest index for both normal and stress conditions. factor analysis determined four and six factors under normal and salt stress conditions that accounted for 65% and 70% of total observed variations of grain yield. these factors were yield components, quality related traits and grain yield and its components. in conclusion, the results of this study identified harvest index and biological yield as important traits in selection for high yielding wheat genotypes.