Genotypes Performance of Brassica Species under Saline Conditions using Salt Tolerance Indices

A two years (2006–2007 and 2007-2008) experiment was conducted at National Salinity Research Center, Yazd, to evaluate salt-tolerant genotypes of Brassica napus, B. rapa and B. juncea. To screen genotypes in the first growing season, 58 genotypes were grown under two irrigation water salinity levels of 2 and 12 dS m-1 in an augmented randomized complete block design with six replicated checks. Nineteen genotypes were screened based on salt tolerance indices from the first growing season. In the second growing season, these screened genotypes were arranged in a split plot experiment in three randomized complete blocks with two irrigation water salinity levels of 2 and 12 dS m-1. Stress tolerance index, arithmetic mean, geometric mean and harmonic mean correlated significantly with grain yield under stress and non-stress conditions, showing that these indices are more efficient to recognize salinity resistance. Three-dimensional and cluster plots and bi-plot analysis showed that Hyola401 and Hyola420 were the most salt-resistance genotypes following by Option501 and RGS003. In addition, CVRoby, Elite, Milena, Okapi, SLM and Zarfam had low yield performance under salt stress. In general, B. napus indicated greater resistance to salinity than other species.