Evaluation of Plant Nutrition Traits Based Genetic Variability to Identify N-P-K Use Efficient Genotypes in Cassava

Abstract

A total of 132 elite genotypes were evaluated to identify N-P-K use efficient genotypes in cassava. The genetic variation was studied through the principal component, cluster, biplot and dendrogram analysis. Principal component analysis (PCA) extracted seven principal components with a cumulative variability of 73.3% with the highest variability (24.1%) in PC1 and the least in PC7 (4.7%). Hierarchical cluster analysis resulted in eight clusters having 62, 29,13,18, 2,5,2 and 1 genotypes in clusters one to eight respectively with each cluster having genotypes with almost similar characters. Biplot indicated the characters important for each genotype and the dendrogram had eight groups with the same genotypes composition as in cluster analysis. These analyses revealed the distinct variation among these genotypes and the genotypes in clusters 1, 2, 3, and 4 were later screened as nutrient use efficient (NUE) too. These included NPK efficient genotypes viz., Acc. No. 7, 775, 788, 796 (cluster 1), Acc. No. 130, 766 (cluster 2), Acc. No. 696 (cluster 3), NP efficient genotypes viz., Acc. No. 890, 896 (cluster 1), Acc. No. 115 (cluster 4) and PK efficient genotypes viz., Acc. No. 662, 905, 906, 908 (cluster 1), Acc. No. 750 (cluster 3). Biplot analysis revealed the characters linked to the genotypes are significant for genotypes in clusters 1,2,3 and 4 which in turn were later delineated as NUE genotypes. These accessions can form a broad genetic base in breeding programmes to evolve genotypes with better NUE.