Genetic Variability and Relative Importance of Nine Phenological and Physiological Characters Studied in Spring Wheat (Triticum aestivum L.)
Abul Awlad KHAN
Pages: 181-186
Summary
Experiment was designed to establish a more definitive relationship of phenological and physiological traits with yield in wheat using twenty five spring wheat genotypes. Because many of these traits are interrelated, correlation coefficient, path analysis and principal component analysis were used to expose these relationships more clearly. Experiment was conducted at the Wheat Research Center, Bangladesh Agricultural Research Institute, Gazipur during the Rabi season of 2009-10. The analysis of variances showed highly significant variations among the genotypes for all the traits studied. The results revealed that moderate to high heritability along with moderate genetic advances for ground coverage, biomass, grain filling duration and grain filling rate offer chances of expected response to selection. The association of phenological traits with grain yield suggests selecting the genotypes with early maturity and relatively long grain filling duration for the development of high yielding wheat cultivars. Significant negative correlation of physiological maturity and canopy temperature with biomass, grain filling rate and grain yield revealed that early maturing genotypes having high biomass can change their physiology to suit with variable environments to attain a high grain yield. Path analysis confirmed physiological maturity, grain filling duration and grain filling rate as major contributing characters for improvement of wheat grain yield through their direct effects. The rest of the traits contributed indirectly either via grain filling duration or grain filling rate. The latent vectors obtained from principal component analysis also identified grain filling attributes, biomass and physiological maturity as major contributors to the differentiation of studied genotypes. Screening of wheat genotypes on the basis of these traits may be more fruitful and may have long lasting effect to supplement empirical breeding approach.
Keywords
phenological and physiological traits, variability, path coefficient, principal component analysis, spring wheat
Full Text: PDF