Evaluation of salt stress of Iranian wheat germplasm under field conditions

Abstract

Salinity is one of the most serious problems of crop production worldwide. In this research, a set of different wheat landraces with high diversity collected throughout Iran, advanced lines in breeding programs, and some well-known tolerant and sensitive cultivars were used to estimate genetic parameters of agronomic traits by using the restricted maximum likelihood (REML) approach. The results showed that several genotypes such as BUMI8, Salt18, BUMI1, Check cultivar and Salt25 had no reduction in grain yield under saline conditions compared with normal conditions. Minimum reductions in grain yield were related to BUMI6, Roshan and Shahpasand genotypes. High broad-sense heritability for most traits showed that they could be used to select and improve the salt tolerance of wheat germplasm in breeding programs. Grain yield had high broad-sense heritability under normal (H2b = 0.61) and saline (H2b = 0.55) conditions. Traits related to height and number of spikes per plant showed a positive correlation with grain yield. Time to heading and to maturity showed negative correlation with grain yield. Number of kernels per spike, kernel weight per spike, number of spikes per plant and spike weight showed positive correlations with grain yield under saline conditions. A significantly negative correlation was also seen between grain yield and days to heading or days to maturity under saline conditions. High variation and moderate to high heritabilities of yield and yield components in normal and salt-stressed field conditions for Iranian bread wheat germplasm are promising to enhance the narrow genetic pool of salinity tolerance.