Genetic variability studies in rice (Oryza sativa) genotypes of Assam for ratooning ability and perennation

Abstract

An experiment was conducted at the research farm of Assam Agricultural University, Jorhat, Assam during 2020–22 to assess the genetic variability among 50 rice (Oryza sativa L.) genotypes with respect to ratooning ability and perennation. Out of 50 genotypes, only 30 genotypes showed different degree of ratoon production and ratoon yield. All the genotypes showing better ratooning ability mainly belonged to photo-insensitive group and only few were slightly photosensitive. True perenniation as expressed by formation of rhizome (O. longistaminata) was not observed in any of the genotypes. However, stolen formation as in O. rufipogon was observed only in 1 genotype Terabali. ANOVA result suggested the presence of statistically significant variability among all the genotypes in both main and ratoon crop. Genotypes, viz. Binadhan-11, Sayjihari and IR-64 were found to be best performing for all the desirable ratoon crop traits. High heritability coupled with high genetic advance was estimated for all the ratoon crop traits except for days to ratoon maturity indicating the involvement of additive gene action in the expression of the traits.