[Genetic diversity and mating system Pinus brutia var. Stankewiczii sukacz. in small localities of Sudak (Crimea)].

A comparative analysis of genetic variation at 12 polymorphic isozyme loci, and the mating system has been carried out in mature trees and their seed progeny in three small localities of Pinus brutia var. stankewiczii Sukacz. near the town of Sudak--settlement of Novyi Svet in the Crimea. We found that embryos maintain the same allelic diversity as mother plants but their observed heterozygosity is lower on the average by 37.4%. The significant deviation of genotype distribution from the theoretically expected ratios caused by the deficiency of heterozygotes was observed at 8 out of 12 loci. Multilocus estimate of outcrossing rate (t(m)) in populations varied from 68.9 to 94.9% making on the average 80.7%.

[Allozyme variation of seed embryos and mating system in relict populations of Scots pine (Pinus sylvestris L.) from the Kremenets Hill Ridge and Maloe Poles'e].

Allozyme variation at ten polymorphic loci and mating system was studied in three small isolated relict populations (4.4 to 22 ha) and in three artificial stands of Pinus sylvestris from the Kremenets Hill Ridge and Maloe Poles'e. It was established that the mean heterozygosity of 130 to 140 year-old trees from natural populations (H(O) = 0.288; H(E) = 0.277) was substantially lower, compared to 30 to 40 year-old trees from artificial stands (H(O) = 0.358; H(E) = 0.330). The observed heterozygosity of seed embryos (H(O) = 0.169 and 0.180) was substantially lower than of the mature trees from populations and artificial stands, respectively. In the embryo samples, irrespectively of the forest stand origin, substantial hetedrozygote deficiency was observed (at six to eight loci), compared to the Hardy-Weinberg expectations. The proportion of cross pollination in the populations and artificial stands was low, t(m) = 0.588 to 0.721; and t(m) = 0.455 to 0.837, respectively.

[Age dynamics of population gene pool of the Crimean pine (Pinus pallasiana D. Don) in Crimea].

Polymorphism of young (14-16 years), middle-aged (70-80 years) and old (120-150 years) plants and their seed embryos has been studied using 20 and 10 allozyme loci correspondingly in the population of Pinus pallasiana D. Don from Mountain Crimea. It was revealed that the old-aged trees had significantly lower level of expected heterozygosity than the young plants. The level of observed heterozygosity of embryos of the uneven-aged plants was slightly different among the embryo samples and significantly lower than in the samples of maternal trees. Supernumerary homozygotation of the embryos is caused by low level of cross-pollination in three studied samples of plants (t(m) = 0,537-0,637).

[Population-genetic variation in Scots pine Pinus sylvestris L. from the main forest regions of Ukraine].

Using electrophoretic analysis of 22 isozyme loci controlling ten enzyme systems, we studied intrapopulation and interpopulation variation of Scots pine Pinus sylvestris L. in the main forest regions of Ukraine. In 15 of the populations examined, 76.5% of genes were polymorphic, and an average plant was shown to be heterozygous at 23.4% of the genes. The lowest and highest values of major polymorphism parameters were characteristic of respectively the relic populations of Ukrainian Carpathians and the populations from the steppe and forest-steppe zones. Nei's genetic distances between the populations varied from 0.006 to 0.031 (on average 0.016). Cluster analysis failed to show clear trends in the population distribution relative to their geographical position.

[Comparative study of allozyme polymorphism in groups of pine trees (Pinus sylvestris L.) with different seed productivity]. / Sravitel'noe izuchenie allozimnogo polimorfizma v gruppakh derev'ev sosny obyknovennoi (Pinus sylvestris L.) s raznoi semennoi produktivnost'iu.

Genotypes of 196 Pinus sylvestris L. plants from 10 natural populations of five Ukrainian regions have been determined using 19 polymorphic isozyme loci. Variability of quantity of full-grained, empty-grained and underdeveloped seeds in the cones of these plants has been studied. The basic indexes of genetic polymorphism were determined for 6 samples presented by 18-19 trees with high and low productivity of the full-grained, empty-grained and underdeveloped seeds. The maximum amount of rare alleles and genotypes as well as the highest heterozygosity (Ho = 0.285) were typical for the sample of plants with the maximum quantity of empty-grained seeds in the cones.