Principal Component Analysis and Clustering of Cassava Germplasm based on N and K Efficiency

Abstract

The present study was undertaken at ICAR-CTCRI, Sreekaryam to identify and group N and K efficient genotypes from a pool of released varieties, pre-breeding lines and elite landraces of cassava during 2021-2022. Thirty genotypes of cassava were evaluated for their diversity based on N and K efficiency along with some of its contributing plant characters using statistical tools like principal component analysis, and dendrogram clustering. The variation existing among the selected genotypes was observed through PCA, where the first six principal components accounted for nearly 81% of the total variability. Characters like tuber yield, plant height, stem girth, tuber length and tuber girth contributed to the greater variability among the genotypes. The dendrogram analysis classified the genotypes into six clusters based on the 18 parameters contributing to nutrient use efficiency. The proportion of the variance accounted by these clusters came up to the extent of 50% displaying the association of the genotypes with similar characters in these clusters. These analyses helped to realize the wide range of variability existing among the selected genotypes for the 18 characters studied.  A simple correlation was also worked out between N and K use efficiency with root traits, which revealed that characters such as weight of storage roots, number of storage roots, and number of basal roots showed a positive correlation with both N and K use efficiency in cassava.