Seed Source Variation in Cone, Seed and Seedling Characteristic Across the Natural Distribution of Himalayan Low Level Pine Pinus roxburghii Sarg

The wide range of climatic condition in the natural distribution of chir pine is expected to result in high genetic variation within different populations of the species. The present study on the provenance variation of chir pine aims to determine the nature and extent of variation in wide range of populations with respect to 23 morphological traits of cone, seed and seedling, (at nursery stage) of 63 provenances of Pinus roxburghii. Seed sources exhibited a wide range of variability in terms of mean vales for various traits, standard deviation, variance, coefficient of variability, broad sense heritability, genetic advance and genetic gain and offer ample scope for undertaking screening for the desired traits. Genotypic variance (V_g) and genotypic coefficient of variability (GCV) for most of the parameters were found to be higher than corresponding environmental variance (V_e) and environmental coefficient of variability (ECV), except cone fresh weight, survival%, days taken for bud break and collar diameter where V_e and ECV dominated the V_g and GCV, thus indicating influence of environment on the expression of these traits. Moderate to high percentage of heritability coupled with same intensity of gain, was observed for many of the traits studied under laboratory conditions and at nursery stage e.g. for germination percentage, MGT, GV. This signifies that these traits are under strong genetic control and good amount of heritable additive genetic component can be exploited for further selection and improvement of this species.