Study Of Correlation Coefficient And Path Analysis Among Yield Parameters Of Wheat: A Review

Wheat is third most important food crop in Nepal after rice and maize. The productivity of wheat in Nepal is lower than world productivity. The causes behind it are drought and heat stresses, genotype, climate change, global warming lack of inputs and irrigation. Yield of wheat is quantitative trait which is adversely affected by environmental factors. Therefore, only genotypic selection is not effective and selection should be based on performance of yield components and morpho-physiological characters. Correlation coefficient analysis provides the direction and degree of relationship between yield attributing characters. Path coefficient analysis helps to analysis direct and indirect effect of one variable to another. It helps in partitioning direct and indirect causes of correlation. Among agronomic trait, days to booting, days to heading and days to maturity show negative correlation to grain yield but chlorophyll content, plant height, spike/m2, number of spikelet/spike, number of grain/spike, spike length, spike weight is directly correlate to grain yield .Spike weight, spike length, thousand kernel weight, and number of spike per meter square, number of grains per spike and days to anthesis has direct positive effect on grain yield and plant height, chlorophyll content and days to heading have negative direct effect on grain yield.