Genetic performance of medicinal landraces in comparison with improved cultivars for nutritive and grain quality traits in rice (Oryza sativa L.)

摘要

Rice (Oryza sativa L.) is the most important food crop in South and South East Asian countries, particularly in developing countries like India. The nutritive and grain qualities cooking of the rice is one of the most serious problems in many rice producing areas of the world. The experimental material used were four traditional medicinal land races and six improved high yielding varieties of Tamil Nadu raised in Randomized Block Design during Kharif 2012-2013. Observation were recorded and analysedforvariability parameters moderate values of PCV, GCVwere observedfor L/B ratio (mm), L/B ratio after cooking (mm), kernel length after cooking (mm), volume expansion ratio, kernel breadth (mm) and amylose content (%) while high PCV, GCV recorded for biochemical characters viz., magnesium (mg/WOg), calcium (mg/lOOg), copper (ppm), zinc (ppm) and crude protein (%) indicated large extent of genetic variability for these traits in the materials studied. The estimates of genotypic variances showed a considerable range of variation for most of the characters. High values of heritability coupled with high genetic advance as per cent of mean were observed for L/B ratio (mm), L/B ratio after cooking (mm), volume expansion ratio, kernel length after cooking (mm),kernel breadth (mm) and amylose content (%) along with high values of all the biochemical traits indicating involvement of additive gene action for these traits and phenotypic selection based on these traits in the future generations would likely to be more effective. When compared with the high yielding varieties, the landraces Veeradangan and Kavuni recorded very high nutritive values viz., calcium, iron and zinc content.