Variance Components of Some Quantitative Characters in 16 Varieties of Rice (Oryza sativa L.) influenced by Different Nitrogen Fertilizer Levels

Abstract

Heritability and phenotypic estimates of some quantitative traits and its influence on different nitrogen fertilizer levels give the room for recombinants which become a prerequisite for any breeding study. Genetic variation in quantitative traits for the development of a new variety of crop plant with different nitrogen fertilizer levels. Based on this background, the study was conducted in order to evaluate the quantitative traits from advanced blast-resistant rice varieties in order to establish relationship between yield and yield components using genetic variances. To achieve this objective, two field studies were carried out in Malaysia during the cropping season 2017/2018. Sixteen advanced blast-resistant rice genotypes were studied in order to find out phenotypic correlation and heritability in some quantitative characters to determine the effect of various levels of Nitrogen fertilizer. The field experiment was conducted in a split-plot design replicated three times in a plot of 35 × 28.5 m2. The planting distance was 25 × 25 cm and the plot size was 2 × 1.5 m2 unit for genotype in each replication. There was a highly significant variation among the genotypes in response to nitrogen levels, high PCV, GCV, heritability, relative distance and genetic advance which indicated that different quantitative traits especially tonnes per hectare (Tha), grain weight per plot (GWTPP) and kilogram per plot (kgplot) significantly influence the yield trait. Similarly, high heritability (>60%) was observed indicating the substantial effect of additive genes more than the environmental effect. Yield per plant showed strong to low positive correlations (𝑟 = 0.99 - 0.09) at phenotypic level for grain weight per plot (GWTPP), number of tillers per hill (NTH), number of panicle per hill (NPH) and kilogram per plot (kg/plot).