Determination of associations between three morphological and two cytological traits of yams (Dioscorea spp.) using canonical correlation analysis

Abstract

Agro-morphological traits of plants may directly or indirectly depend on cytological traits. Thus, the determination of associations between morphological traits (absence or presence of wings, number of stems per plant and wing colour of stem) and cytological traits (DNA content and ploidy level) of yams were investigated using canonical correlation analysis. This multivariate technique is used in wide fields of study to quantify the mathematical relationships between multiple sets of independent and dependent traits or properties. Canonical weights and loadings indicated that DNA content (pg) had the highest contribution to the variation of the morphological traits (presence of wings, number of stems per plant and wing colour) compared with ploidy level. It was found that cytological traits accounted for 0.09 to 0.17% of the variation in the selected morphological traits. The first and second canonical correlations exhibited 60.91 and 39.09% overlapping variance of the canonical variate sets respectively. The first and second canonical variates extracted 0.57 and 4.43% of the total variance in the cytological trait set. The study demonstrated the successful determination of complex inter-relationships between morphological and cytological traits. Key words: Canonical correlation, morphological traits, cytological traits, yam.