Half-sib family variation in shoot and root traits of seedlings of Pterocarpus angolensis (family: Fabaceae; syn. Papilionaceae)

Abstract

Phenotypic and genetic variation in shoot and root traits occurs between half-sib families from Malawi. Heritability was high for shoot height and root collar diameter (h ² ≤ 0.90) while that for shoot and root traits was low to moderate. High phenotypic (r = 0.82–0.91) and genetic correlations (r_g = 0.70–0.90) existed between shoot traits and between shoot and root traits. Root length was poorly correlated to the other traits. The heritability for shoot and root traits obtained in this study indicates that a large proportion of the phenotypic variance can be explained by genetic variance. Selection for genetic improvement in seedling growth and survival can successfully use shoot height or root collar diameter. Early selection focusing on families is possible and substantial genetic gains may be achieved through selection for progeny evaluation, assuming a good correlation between juvenile and mature traits exists.