Variation in Cone and Seed Morphology of <I>Pinus roxburghii</I> Sargent : Effect of Population and Mother Tree

Abstract

A study was undertaken to estimate the structure of variation in cone and seed traits of Pinus roxburghii through three-level nested (hierarchical) classification model. The populations studied constituted a continuous stretch of this species. Between-population variation for the cone and seed characteristics was found to be very small as it ranged from 0 per cent to 26 per cent, depending upon the trait. The remaining 74 per cent or more of the variation in these characters was due to the between-tree within-population and the within-tree components. The study showed that if seed collectors are interested in cones of greater weight or length, they should search for trees possessing such cone or seed characteristics within their own planting region, rather than trying to find specific populations for such characteristics outside their planting region, because much of the variation in these traits is accounted for by differences between trees, rather than between populations. Else, they should search for desired stands in distantly located populations or in populations separated by some geographic barrier.