Morphological characterization of asiatic cotton (G. arboreum) germplasm of India

Abstract

A set of 816 accessions of desi cotton (G.arboreum) were evaluated in augmented design 1 during Kharif 2015-16. Traits namely 
stem color, leaf size, leaf lobbing, leaf shape, leaf color, petal color, bract size, boll shape, boll size, leaf nectaries, and plant type 
were recorded. Principal Component Analysis (PCA) identified five principal components were accounted for a cumulative 
variation of 86.36%. The first principal component accounted for 40.37%, second for 17.43%, third for 11.32%, fourth for 9.75% 
and fifth for 7.50% of total variation. First principal component (PC 1) was correlated with boll shape (0.94) and bract size 
(0.10). Second principal component (PC 2) was associated with leaf shape (0.98) and bract size (0.11). PC 3 was correlated with 
bract size (0.74) and boll size (0.24). Forth PC (PC 4) was associated with nectarines (0.82) and bract size (0.57). Fifth PC (PC 5) 
was related with leaf lobbing (0.97). Maximum diversity index was recorded for the trait stem color (6.70). The trait leaf shape 
showed lowest diversity index (6.472), followed by boll shape (6.492) and nectar (6.570). Lower the diversity index 
discriminated the accessions in higher order.  Principal Component Analysis (PCA) based on qualitative traits revealed that traits 
namely boll shape, leaf shape and bract size distinguished all genotypes in higher order than other traits. Convex of the hull 
occupied by the genotypes namely A 32, AC 30, AC 32, AC 543, AC 544 and 78/1A, these genotypes showed the highest point 
among the factors. All the genotypes were grouped into six distinguished clusters.