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Investigations were made to determine the nature and extent of variations present for 10 morphological characters of cone,seed and seedlings of 17 plus trees(PTs)of Pinus kesiya growing in eastern Himalayas(Meghalaya state) of India.The significant variations has been observed in cone weight,cone length,cone diameter,seed length,seed diameter,seed weight,number of seeds per cone,seed germination,seedling height and seedling collar diameter among different PTs of the species.Significant positive correlation(p 0.01) between seed weight,cone length and cone diameter showed that seed weight in P.kesiya depend more on the cone size.Seed germination is found positively correlated(p 0.01) with seed weight,seed diameter,cone size and number of seeds per cone in the study.Among geographical factors,latitude and altitude are found positively correlated(p 0.05) with cone weight and seed diameter,respectively.The genetic parameters for seed,cone and seedlings of PTs of P.kesiya also showed a wide range of variability in terms of variance,coefficient of variability,broad sense heritability,genetic advance and genetic gain.Seed weight,seeds per cone and seedling diameter showed high heritability values([75) coupled with maximum genetic gain.Traits with such values indicate the presence of good amount of heritable additive components and are under strong genetic control.The findings of the study revealed that PTs expressed both phenotypic and genotypic differences in the seed,cone and seedling characters,which may be attributed to the differences in genetic makeup of various PTs and environmental factors i.e.genotypic and environmental interaction.The presence of high variability in P.kesiya PTs for different characters provide further opportunities to improve the population in subsequent generations so as to establish this species as an important timber tree to be grown on less fertile and degraded soils in its distributional ranges.
Investigations were made to determine the nature and extent of variations present for 10 morphological characters of cone, seed and seedlings of 17 plus trees (PTs) of Pinus kesiya growing in eastern Himalayas (Meghalaya state) of India. The significant variations have been observed in cone weight, cone length, cone diameter, seed length, seed diameter, seed weight, number of seeds per cone, seed germination, seedling height and seedling collar diameter among different PTs of the species .Significant positive correlation (p 0.01) between seed weight, cone length and cone diameter showed that seed weight in P.kesiya depend more on the cone size. Seed germination is found positively correlated (p 0.01) with seed weight, seed diameter, cone size and number of seeds per cone in the study. Amorphous geographical factors, latitude and altitude are found positively correlated (p 0.05) with cone weight and seed diameter, respectively. genetic parameters for seed, cone and seedlings of PTs of P.kesiya also showe da wide range of variability in terms of variance, coefficient of variability, broad sense heritability, genetic advance and genetic gain. Seed weight, seeds per cone and seedling diameter showed high heritability values ([75) coupled with maximum genetic gain .Traits with such values indicate the presence of good amount of heritable additive components and are under strong genetic control. The findings of the study revealed that PTs expressed both phenotypic and genotypic differences in the seed, cone and seedling characters, which may be attributed to the differences in genetic makeup of various PTs and environmental factors iegenotypic and environmental interaction ie presence of high variability in P.kesiya PTs for different characters provide subsequent opportunities to improve the population in subsequently generations so as to establish this species as an important timber tree to be grown on less fertile and degraded soils in its distributional ranges.