[Changes in phenolic acids during maturation and lignification of Scots pine xylem].

The content and fractional composition of alcohol soluble phenolic acids (PhA) in cells with different degree maturation and lignification in the course of early and late timber formation in the pine (Pinus sylvestris) during vegetation were studied. Phenolic compounds (PhC), extracted by 80% ethanol, were divided into free and bound fractions of PhA. In turn, the esters and ethers were isolated from bound PhA.

[The changes in contents and composition of phenolic acids during cell xylem growth in scots pine].

The contents and composition of alcohol soluble phenolic acids were studied during cell xylem growth in the course of wood annual increment formation in the stems of Scots pine. The cells of cambium zone, of two stages of expansion growth and the outset of secondary thickening zone (before lignification) were successively gathered from the stem segments of 25-old pine trees in the period of earlywood xylem formation with constant anatomical and histochemical control. The contents of free and bound forms of phenolic acids, isolated by 80% ethanol from tissues, as well as of their ethers and esters were calculated both per dry weight and per cell.

[Effect of the complex of technogenic and recreational loads on development of trunk tissues of Scotch pine in the Krasnoyarsk forest-steppe].

The morphometric parameters of trunk tissues of Scotch pine in suburban pine forests of Krasnoyarsk are studied, which grow under the long-term impact of technogenic and recreational loads in comparison with the background. Technogenic and recreational loads decrease the intensity of work of the cambium, especially towards the xylem, its duration, the cell size, and the structure of storage tissues. In pine stands of the Krasnoyarsk forest-steppe, the effect of the complex of anthropogenic stressors is weakening and degradation of forest stands and inhibition of production process at the cell and tissue levels are taking place.

[Seasonal development of phloem in Siberian larch stems].

The seasonal development of phloem in the stems of Siberian larch (Larix sibirica Ldb.) was studied over two seasons on 50-60-year-old trees growing in a natural stand in the Siberian forest-steppe zone. Trees at the age of 20-25 years were used to study metabolites in differentiating and mature phloem elements, cambial zone, and radially growing xylem cells in the period of early and late wood formation.

[Seasonal development of phloem in Scots pine stems].

The formation of phloem was studied for two years in stems of 50 to 60 year old trees of Scots pine (Pinus sylvestris L.) growing in nature. The development of phloem of the current year begins 10 to 20 days before the xylem formation and is completed with the termination of shoot growth in the end of June.