Multivariate Analysis Of Potato Genotypes For Genetic Diversity

Abstract

Sustainable production of food crops relies on germplasm improvement and genetic diversity that helps to identify appropriate parents, which is very important step in breeding of genotypes having high yield potential for future use. This study was conducted to investigate the extent of genetic diversity using multivariate technique on the basis of qualitative and quantitative traits. An experiment was comprised of 74 exotic genotypes and started at National Agriculture Research Center Islamabad, Pakistan during autumn 2017-2018 and 2018-2019. Data was recorded on qualitative and quantitative traits by following standard procedures and Biplot analysis was used to calculate the significance among the studied quantitative traits to exhibit the strength of relationship between traits. Results showed significant diversity in qualitative traits and quantitative traits. Red, yellowish, brown, light yellow, light brown color tubers were produced. Alike, genotypes produced yellow, cream and white flesh color tubers. Genotypes had oval, round, oblong, elliptic and reform with medium, small and large size tubers. Alike, brown, light brown, dark red and yellow eyes color was noted. In case of quantitative traits, genotypes had high variance regarding plant height, leaf area and number of tubers per lane. Genotypes had very high genetic variance for weight of tuber per plant and weight of tuber per lane while low variance was recorded for germination, number of stem per plant and number of eyes per tuber. Significant positive correlation was observed between number of tubers per plant (TPP) with number of eyes on tubers (r = 0.241) and number of tubers per lane (TPL) (r = 0.349). But negative correlation was noted between number of tubers per plant (TPP) with plant height (r = - 246), leaf area (-0.529) and germination (r = -0.283). Plant height was found significantly positive correlated with leaf area (r= 0.456), germination percentage (r = 0.255) and weight of tubers per plant (r = 0.307). Leaf area (LA) showed positive significant correlation with number of tubers per plant (r = 0.466) and weight of tubers per plant (r = 0.263)., yield and harvest index (r = 0.798, 0.755, 0.255). Weight of tubers per lane (WTL) showed positive correlation with weight of tubers per plant (r = 0.387). Regarding the interrelation between the traits and genotypes, the first two principal component axes (PC1, 24.83% and PC2, 23.46%) accounted for about 48.29% of the total variability reflecting the complexity of the variation between the plotted traits of genotypes.