Application of growth traits and qualitative indices for selection of Scots pine (Pinus sylvestris l.) elite trees. A case study from Volyn region, western ukraine

Since the plus trees are selected based on phenotype, it is necessary to evaluate them in progeny test. The aim of this study is an indication of selecting elite mother trees based on the results from half-sib progeny test trials. As study sites, two Scots pine half-sib progeny tests were selected. During evaluation, the progenies had reached the age of 38 and 40 years, respectively. In both progeny trials, quantitative parameters and qualitative traits of Scots pine half-sib progenies were investigated. Based on these data, complex evaluation of half-sib families was carried out. We concluded that, Scots pine progenies at the age of 38 and 40 years in fresh and moist mixed forests are characterised by acceptable quality, with the survival being 25%–33% per progeny test trial. Based on a complex evaluation of 38- and 40-year-old half-sib progenies of plus trees, we proposed to select 31% of tested plus/mother trees as candidates for elite trees. Further, the list of candidates for elite trees was created with five plus trees from the Volyn region (26% of the total tested from the region) and four plus trees from the Lviv region (40% of the total tested from the region). With age, the share of the best and undesirable trees decreases, while the proportion of intermediate trees increases in both control trees and half-sib progenies. At the age of 38 and 40 years, the proportion of fast-growing offspring was from 0% to 36%, while the declining trend that was observed in previous years was being continued. Thus, due to the declining trend in the proportion of fast-growing offspring observed at the age of 38 and 40 years, we propose to select candidate trees for an elite group not early than after 40 years of test their progenies.

AFLP markers for analysis of genetic diversity and structure of teak (Tectona grandis) in India

Five amplified fragment length polymorphism (AFLP) primer combinations (E-AAC × M-CAT, E-AAC × M-CTG, E-ACA × M-CTC, E-ACA × M-CTA, and E-ACC × M-CTA) were employed for analysis of genetic diversity, differentiation, and structure of 96 genotypes of teak (Tectona grandis L. f.) from 10 natural locations in India. The analysis of the AFLP marker data by both versions, i.e., GST and θ, of F statistics showed a similar trend due to the outcrossing nature of teak. The primer combination E-AAC × M-CAT detected maximum polymorphism in the teak genome. The analysis of molecular variance assigned a large proportion of the genetic diversity to within sampled locations and a very small proportion to among locations. The population genetic structure resolved by the neighbor joining tree, principal coordinate analysis, and no-admixture and admixture model Bayesian-based analyses irrefutably revealed two distinct centers of teak diversity, i.e., central India and peninsular India. Furthermore, the very high proportion of genetic diversity residing within locations encourages the intensive selection and (or) collection of diverse superior genotypes (elite trees) from each location for the conservation of germplasm and the genetic improvement of teak.

Effects of the time of cuttings collection and IBA concentration on the rooting of softwood cuttings from elite trees of Cornelian cherry (Cornus mas L.) in Belgrade area

In this study, the effect of concentration of indole-3-butyric acid (IBA) (powder dip), cutting type as well as the time of taking cuttings on the rooting of softwood cuttings of cornelian cherry was examined. Four types of cuttings were used: basal cuttings, terminal cuttings, basal cuttings with 2-year-old wood and terminal cuttings with 2-year-old wood. The obtained results showed that IBA concentration, cutting type and time of collecting have significant effect on rooting. The best results were obtained using 1% IBA and cuttings collected in the second term (in mid-July) had a higher rooting percentage. Terminal cuttings treated with 1% IBA (powder dip) should be used for optimum results. In that case the rooting percentage was very high (over 90%) in both terms of cuttings collection.

A Novel Gel-based Method for Isolation of Stigmas During Controlled Pollination Experiments

In forestry, controlled pollination (CP) allows the combining of genetic material of selected elite trees to produce high quality, and consequently high value, seed. The aim of the present study was to develop a novel isolation method that would allow the technique to be conducted without expensive and time-consuming bagging, making CPs on small-flowered eucalypts commercially viable. We compared the current method of isolating inflorescences using exclusion bags to a novel method which uses sodium alginate gel. Sodium alginate was effective in keeping external pollen away from the stigma, since no seed was produced in those treatments that were not manually pollinated but isolated in this way. In addition, flowers hand-pollinated and isolated with sodium alginate produced progeny that were 100% outcrossed with the applied pollen. The exclusion bags, on the other hand, were not as effective in protecting the stigma as seed was produced in those treatments that were isolated with an exclusion bag without being handpollinated. Sodium alginate isolation also increased the efficiency of control-pollinations as the gel was naturally shed, removing the need for operators to return to the tree to remove the isolation material.