Abstract
Phenotypic variability in agronomic important traits is prerequisite for the genetic improvement of crop plants. The generation
and phenotypic characterization of mutants are helpful to select genotypes with improved agronomic traits. The present study
was planned to evaluate the phenotypic variability among mutants for their agronomic important traits in first and second
mutagenic generation of super basmati against ethyl methane sulphonate treatments. Data recorded at maturity were
statistically concluded using principal component analysis under ten different parameters (germination, number of
spikelet/plant, tiller/plant, panicle length, yield/plant, 100 paddy weight, plant height, paddy length, paddy width and paddy
length width ratio). The results showed that EMS doses up to 1.5% are the best for generating mutant genotypes of super
basmati. Number of spikelet/plant, yield/plant, tiller/plant and 100 paddy weight demonstrated the highest variation in both
mutagenic generations of super basmati. Significant correlation and the greatest contribution in total variability were existed
among number of spikelet/plant, tiller/plant and plant height during both mutagenic populations of super basmati. First two
principle component of bi-plot explained 52.62% and 54.50% of total variance in first and second mutagenic population of
super basmati, respectively. It is concluded that ethyl methane sulphonate treatments up to 1.5% might be initiated a
considerable level of genetic variability in mutant lines of super basmati. This genetic variability should be used for advance
study such as for selection of rice mutant genotypes in mutation breeding program.
