Study on ethyl methane sulfonate (EMS)-induced variability in morphological traits of rice and identification of mutant lines with high yield potential

Induced mutation is one of efficient methods for improvement of qualitative and quantitative traits in crop plants. A research was conducted to study on variability of morphological traits in rice after application of ethyl methane sulfonate (EMS). Neda cultivar was treated by 0.1% EMS mutagen and then variability of qualitative and quantitative morphological traits were evaluated in 212 M2 mutants. On the basis of visual observations, stem color and its angle were altered in two and five mutant lines, respectively and two aromatic lines was identified based on aroma test. Also, mean of plant height and heading date, showed significant decrease and relatively significant increase, respectively. Twenty two mutant lines were selected based on further tillering and vigor and along with original cultivar were evaluated in some quantitative traits. ANOVA showed that there were very significant differences between the studied genotypes in all evaluated traits. The effect of this selection was desirable on most studied traits, so that highest effect was observed on filled kernels/panicle (41.3%), total kernel number (37.4%), tiller number (29.4%, plant yield (25%), plant height (-5%) and lowest effect was observed on 100-kernel weight (-0.05%) and heading date (2.4%). Seven lines produced significantly higher yield than original cultivar, that in most of them total kernel number and filled kernels showed a significant increase relative to original cultivar. Based on mean comparison three mutant lines viz. MT-A, MT199 and MT44 were identified as high-yielding lines. On the basis of the results of this research it can be concluded that mutation technique is a suitable tool for inducing genetic variability in different rice traits and that visual selection in M2 generation is efficient for identification of high-yielding mutant lines.