Estimation of genetic parameters on growth characteristics of a 35-year-old Pinus koraiensis progeny trial in South Korea

The effects of genetic and environmental factors on Pinus koraiensis growth were studied based on a35 year-old progeny trial composed of open-pollinated offspring of twenty-one plus trees.Height,DBH and volume of the offspring was analyzed using restricted maximum likelihood/best linear unbiased prediction in mixed model analysis.Significant site and family effects on the three traits were observed.The distinct growth of offspring by site with disparate climates corroborated the importance of planting species in suitable conditions.Growth differences by family was significant,emphasizing the importance of identifying families with either superior or inferior performance.The parental ranking was assigned in the sites,inferring the breeding value of each plus tree.The estimates of individual heritability(h_(i)^(2))of height,DBH and volume growth were 0.169-0.645,0.108-0.331 and 0.129-0.343 respectively,with higher h_(i)^(2) of the height than DBH on each site.Coefficient of variance of genetic effect was higher with DBH in some cases,indicating the scope for selection is larger for this trait despite the lower heritability compared to height.For the variation between families in terms of the performance stability across sites,consideration of the genotype by environment interaction is required in selecting materials to be used in reforestation with Korean pine.A few families with either superior or inferior performance retained their parental ranking for at least a decade.Other families with increased growth on a particular site were identified,indicating their high breeding value and low stability.Differences in the genetic performance of the families by site requires delineation of the breeding region of the species.

Variability in pod and seed traits of Pongamia pinnata Pierre ecotypes in North Karnataka, India

An evaluation of 30 naturally available candidate-plus trees（CPTs） of Pongamia pinnata was carried out to elucidate the genetic variability and relationship of pod and seed traits and progeny growth traits to select the best planting material with higher productivity. Significant variations were observed in pod and seed characteristics,oil content, and during the progeny trial studies. The highest values were found in 100-pod weight（410.4 gm）and 100-seed weight（195.92 gm） and the phenotypic and genotypic variance was found maximum in 100 pod weight（4364.71 and 4289.93） and 100 seed weight（813.8 and768.93）, respectively. Estimates of the phenotypic coefficient of variance were higher than the genotypic coefficient of variance for all the pod and seed traits and progeny growth traits, which depict the predominant role of the environment. Approximately 99 % of broad-sense heritability was revealed in oil content, followed by 100-pod weight（98.28 %）, and canopy growth（96.93 %）. Pod thickness shows the highest genetic advance of 56.61 %,followed by pod width（53.43 %） and canopy growth（49.3 %）. Pod and seed traits have proven a positive correlation between each other and with progeny growth traits,except a few negative values. Hierarchical clustering by Ward＇s minimum variance cluster analysis showed phylogeographical patterns of genetic diversity. K-means clustering revealed that trees from different geographical regions were grouped together in a cluster where as trees from the same geographical area are placed in a different cluster. Seven Pongamia ecotypes（GRP-8, 9, 13, 14, 18,28, and 29） are found superior in traits, namely 100-pod weight, 100-seed weight, oil content, germination rate,plant height, canopy growth, and collar diameter. The traits100-pod weight and 100-seed weight are highly correlated with the progeny growth traits and even have higher heritability and genetic advantages.