Heritability, Genetic Gain, Correlation and Principal Component Analysis in Introduced Willow (<I>Salix</I> Species) Clones

Abstract

Juvenile growth traits were studied in the recently introduced clones of Salix species from twelve countries including Croatia, Sweden, Italy, Hungary, Turkey, Japan, Yugoslavia, UK, Belgium, New Zealand, Germany and USA which were screened in the nursery by applying 'augmented completely randomized design' with three check clones (SI-64-017, SI-63-007, Kashmiri willow). Significant differences were recorded for morphological traits among test clones and test verses check clones except in leaf length among test clones and volume index, leaf length and petiole length among check verses test clones. The clones SI-63-016, J-799, PN-722, NZ-1002, PN-733, PN-731, SN-2, S × 61, 194 and 084/03 were found superior to check clones for the growth traits viz., plant height, basal diameter and volume index. Heritability in broad sense (91.08 %) and genetic gain (75.24 %) was found highest for leaf breadth and volume index, respectively. Maximum positive and significant correlation coefficient (0.959) was recorded for basal diameter with volume index. Principal component analysis through correlation matrix revealed that three out of eight components contributed 85.03 per cent of the overall variation out of which the first principal component (λ=3.086) explained 38.57 per cent of the variance weighted maximum (0.937) by volume index. These promising clones selected under the present study will be further tested under multi-location trials to study the genotype x environment interaction at different sites for analysis of suitability of clones.