Genetic diversity in mutated and non-mutated rice varieties

Area of Science:

• Agricultural Science
• Genetics
• Plant Breeding

Background:

• Mutation breeding is a key strategy for enhancing crop genetic diversity.
• Gamma radiation is a widely used mutagen for inducing genetic variations in plants.
• Understanding the impact of radiation dosage on specific crop traits is crucial for effective breeding programs.

Purpose of the Study:

• To investigate the genetic variability induced by gamma radiation (10, 15, 20 Kr) in twelve rice genotypes.
• To assess the effects of gamma irradiation on various yield and yield-related traits in rice.
• To determine the optimal gamma radiation dose for creating genetic variability in rice germplasm.

Main Methods:

• Twelve rice genotypes were subjected to gamma irradiation at doses of 10, 15, and 20 Kr.
• Mutated and non-mutated seeds were sown using a split plot design in field trials.
• Data on yield and yield-related traits, including plant height, panicle length, grains per panicle, and 1000-grain weight, were recorded.

Main Results:

• Significant genotypic and irradiation effects were observed on yield and yield-related traits (P < 0.05).
• Gamma radiation at 20 Kr resulted in minimum values for plant height, grains per main panicle, 1000-grain weight, and grain weight per main panicle in specific genotypes.
• Broad sense heritability ranged from 72.0 to 97.7%, and positive phenotypic and genotypic correlations were found between yield-related traits, indicating selection potential.

Conclusions:

• Gamma radiation, particularly at 20 Kr, effectively induces genetic variability in rice germplasm.
• Traits like grain weight per main panicle, panicle length, fertility percentage, 1000-grain weight, and plant height are valuable for yield selection.
• The study demonstrates the potential of mutation breeding using gamma rays to improve rice varieties.