GENETIC VARIABILITY AND AROMA STUDIES IN LANDRACES AND CULTIVARS OF ORYZA SATIVAAkhtar Sabina
Nature and magnitude of genetic variability was estimated in 116 genotypes (42 landraces and 74 cultivars) of rice. These rice cultivars/landraces were grown in replicated trials during the kharif season. Morphological traits were characterized using standard procedure of IRRI on the basis of scales (scores 0 to 9). Leaf blade colour and collar colour was predominantly green in more than 80.0 percent genotypes, while auricle colour, ligule colour and seed coat colour was desirable in most of the genotypes (54 to 90%). Flag leaf angle was erect/intermediate in nearly 60 per cent genotypes. Panicle type was compact/intermediate in nearly 85 per cent population with its threshability as intermediate to easy in about 77 per cent. Estimates of coefficient of variation (phenotypic and genotypic) was high (>30%) for leaf width, tillers plant-1 and grain yield (q ha- 1). Heritability estimates (broad sense) were high (>60%) for all the 10 quantitative traits studied. Expected genetic gain (% of the mean) was high (>30%) for all the traits except plant height and leaf length (data pooled over years). Preliminary screening of these cultivars/landraces for their kernel aroma on cooking revealed that the majority (71.6%) had no aroma, 25.0 per cent were having slight aroma while 4 landraces viz. Tilazag, Mushka budji, Larbeol and Kamad had a presence of good kernel aroma on cooking.