Screening of Rice Genotypes against Blast Disease in Blast Screening Nursery at Parwanipur, Bara

Abstract

: Various rice genotypes received from National Rice Research Program, Hardinath, Dhanusha were tested against leaf blast disease at DoAR, Madhesh province, Parwanipur, Bara in 2020 and 2021. During 2020 four hundred and seven rice genotypes including susceptible and resistant check were evaluated whereas four hundred and sixty four rice genotypes including checks were evaluated in the year 2021. Sesbania bispinosa (Dhanicha) was planted around screening nursery to augment the diseases. Rice nursery was sown in single row of 1 m length designated for one entry and rows to rows distance maintained at 0.15 m. The disease scoring was done at 25 days after seeding using 0-9 scale for rice. During 2020, out of 407 evaluated genotypes; 32 genotypes were immune, 102 genotypes were resistant, 225 genotypes were moderately resistant, 38 genotypes were moderately susceptible, and 10 genotypes were susceptible against rice blast disease. During 2021, out of 464 genotypes evaluated 266 genotypes were immune, 161 genotypes were resistant, 35 genotypes were moderately resistant, and 2 genotypes were moderately susceptible against rice blast disease. The immune and resistant rice genotypes can be used as source of blast resistance for developing improved rice cultivars in future breeding program.