Evaluation of some vegetative traits, percentage of stem borer, blast disease and leaf sheath blight incidences in rice mutant genotypes

To evaluate some agronomic traits and resistance to diseases and pests in some local rice (Hassani, Anbarboo and Tarom Mahalli) mutants, field experiments were conducted in two locations (Amol and Goldasht) under a randomized complete blocks design with three replications in 2019. Plant material included eight mutant genotypes along with Tarom Mahalli and Shiroodi cultivars as control varieties. Measurements were made on seedling height, plant height, number of fertile tillers, percent of dead heart, leaf blast and sheath blight at vegetative stage. Results showed that at transplanting, five genotypes had lower seedling height than Tarom Mahalli but all genotypes had higher seedling heights than Shiroodi cultivar. The number of tillers in mutants varied between 16.5 to 18.5. The percentage of stem borer damage (dead heart) was 1.7 percent for Tarom Mahalli, which was not significantly different from that of the mutant genotypes. The highest percentage of leaf blast incidence was 5.7% which belonged to mutant 215 and the lowest one was 0.74% in Shiroodi and mutant 3200. The highest percentage of leaf sheath blight among the mutants was 3.5% that belonged to mutant 2310 and was not significantly different from other mutants except for mutants 1120 and 215. Plant height and leaf sheath blight percentage were not affected by location, but number of tillers per plant and blast disease percentage were higher in Goldasht than in Amol. As a result, the relative tolerance of mutants to important pests and diseases was acceptable.