FEATURES OF THE SEASONAL DEVELOPMENT OF CONIFEROUS INTRODUCENTS IN THE ARBORETUM OF VSUFT OF VORONEZH

The state and seasonal development of coniferous introducers in the arboretum of VGLTU was studied. Increased anthropogenic pressure on the territory of the arboretum, changes the age state of the collection, outbreaks of activity of diseases and pests of woody plants occur. In this regard, it is important to monitor the state of the plants of the collection, which includes measuring the morphometric parameters of plants, establishing the level of variation of characters, studying the seasonal growth and development of introducents. Differences in the occurrence of phenophases in different species are associated with biological characteristics and weather conditions of the year of observation. For forest-steppe zone Picea glehnii (Fr. Schmidt) Mast. begins and ends the growing season later compared to Pinus pumila (Pall.) Regel. and Abies holophylla Maxim. Seasonal shoot growth is consistent with breed biology. The regularities of individual phenotypic variability of the vegetative sphere are revealed. The most stable is the variation of characters in Picea glehnii (Fr. Schmidt) Mast. (C.V. = 6.5 - 22%). The variability of characters in Pinus pumila (Pall.) Regel. from medium to high level (C.V. = 14.6-21%). At an average - high level, the parameters of Abies holophylla Maxim change. (C.V. = 14-36%). Pinus pumila (Pall.) Regel. and Abies holophylla Maxim. are more sensitive to environmental factors in the conditions of the arboretum, this is manifested in an increase in the variation of the signs of the vegetative sphere.

Inheritance of basic density and microfibril angle and their variations among full-sib families and their parental clones in Picea glehnii

Picea glehnii is one of the most important plantation species in Hokkaido, Japan. Basic density (BD) and microfibril angle (MFA) of the S2 layer in latewood tracheid in 16 full-sib families and their six parental clones planted in Hokkaido were examined to clarify among-family and clonal variations of wood properties and their inheritance from parents to offspring. Mean values of BD and MFA in full-sib families and parental clones were 0.36 and 0.35 g cm-3 and 16.1° and 10.7°, respectively. Estimated repeatabilities of BD and MFA in juvenile wood (jW) were higher than those in mature wood. In addition, larger genetic coefficient of variation was detected for jW, indicating that improvement of jW properties is important to Hokkaido’s tree breeding program. Parent-offspring correlation coefficients were positive and significant in all properties. These results suggest that the influence of parental clones on wood properties is inheritable to offspring. Moreover, there were no significant differences between reciprocal crosses of wood properties, suggesting that plus-tree clones with good wood properties can be used as either female or male parents for producing offspring. There is a possibility of improving wood properties in P. glehnii by crossing clones with desirable properties.