Field Evaluation and Molecular Analysis of Three Early Flowering Canola Mutants under Natural Salinity-Stressed Environment

Abstract

Mutagenesis is a good way to create new plant lines having desirable traits. Therefore, this study was conducted to evaluate three gamma ray-induced early flowering canola mutants, their parent (Serw4) and chick verity (Serw6). Some agronomic traits were evaluated at M6 and M7 generations, under natural saline conditions. The results revealed that all the mutants were earlier and had more seed yield production than their parent and the chick in both two generations and combined. Otherwise, the mean performance of the other studied traits is significantly decreased. Furthermore, the ability of the mutants for salt stress tolerance was evaluated in vitro by treating seedlings with different concentrations of NaCl. All the mutants were the most salt tolerant. On the other hand, genetic diversity and similarity relationships among all genotypes were measured by inter simple sequence repeat (ISSR) molecular marker. The percentage of polymorphism was 50%, while the highest similarity was 0.90 between Serw4 and Serw6, but the lowest similarity (0.79) was detected between Serw6 and M11-4-1 mutant. Moreover, the dendrogram classified all the genotypes into two main clusters, the mutant's parent and the chick variety were gathered in one cluster, while all the mutants were collected in the other one. These induced earlier flowering mutants having higher seed yield production and salinity tolerance, suggested that these mutants could be new great promising mutant lines.