В 30-летнем клоновом архиве на научном стационаре «Кедр» Института мониторинга климатических и экологических систем СО РАН изучены фенология, продуктивность, интенсивность газообмена и устойчивость к биотическим факторам у климатических экотипов кедра сибирского (Рinus sibirica Du Tour) с широтного (от лесотундры Западной Сибири до низкогорий Западного Саяна) и долготного (от Урала до Северного Прибайкалья) профилей. Установлено, что для кедра сибирского характерен высокий уровень наследственно обусловленной эколого-географической дифференциации по продуктивности и устойчивости к биотическим факторам (вредителям и болезням) при выращивании вегетативного потомства на юге лесной зоны. Главным фактором различий между экотипами является теплообеспеченность вегетационного периода в местах их происхождения. С севера на юг она увеличивается значительно сильнее, чем с востока на запад, поэтому различия между широтными экотипами значительно больше, чем между долготными. Интенсивность дыхания в большей степени, чем интенсивность фотосинтеза, зависит от климата, в котором сформировалась данная популяция. У экотипов из холодных местообитаний значительно выше наследственно обусловленные затраты на дыхание. Это является важным фактором снижения их продуктивности в более теплом климате. Будучи ослаблены дисбалансом между фотосинтезом и дыханием, они повреждаются вредителями и болезнями, что становится важным фактором дальнейшего снижения продуктивности. В условиях глобального потепления экотипы из более теплого климата не уступают местному экотипу по устойчивости и превосходят его по продуктивности, поэтому их рекомендуется активно использовать в селекционной работе. The phenology, productivity, intensity of gas exchange and resistance to biotic factors in climatic ecotypes of Siberian stone pine (Рinus sibirica Du Tour) from latitudinal (from the West Siberian forest tundra to the low mountains of the Western Sayan) and longitude (from the Urals to the Northern Baikal region) profiles were studied in the 30-year clone archive at the scientific field station «Kedr» of the Institute for Monitoring of Climatic and Ecological Systems, Siberian Branch of the Russian Academy of Sciences. It has been established that Siberian stone pine is characterized by a high level of hereditarily determined ecological and geographical differentiation in productivity and resistance to biotic factors (pests and fungi diseases) when growing vegetative progeny in the south of the forest zone. The main factor of differences between ecotypes is the heat supply of the growing season in their places of origin. It increases significantly more from north to south than from east to west. Therefore, the differences between latitudinal ecotypes are much greater than between longitudinal ecotypes. The intensity of respiration depends more than the intensity of photosynthesis on the climate in which a given population was formed. Ecotypes from cold habitats have significantly higher respiration costs. This is an important factor in reducing their productivity in warmer climates. Being weakened by the imbalance between photosynthesis and respiration, they are damaged by pests and diseases which becomes an important factor in further reducing productivity. In conditions of global warming, ecotypes from warmer climates are not inferior to the local ecotype in terms of resistance to biotic factors and surpass it in productivity. Therefore, they are recommended to be actively used for breeding.

On the example of Siberian stone pine, seed productivity was analysed in two stands that differed in origin and formation conditions. The cone yield was analysed in years with different levels of seed production in the period from 2016 to 2019. In terms of the number of cones per tree, the sub-settlement Siberian stone pine forest was 2-3 times superior to the taiga Siberian stone pine forest. The level of individual variability in the number of cones in the near-settlement Siberian stone pine forest was significantly lower than in the taiga forest. There is reason to believe that the high level of variability is likely related to a more pronounced differentiation of the stand by crown size. The number of dead ovules in the Siberian stone pine forest in settlement is 60-70% higher than in the taiga forest. Due to high “mortality” of ovules and high variability of this trait, the number of filled seeds in the near-settlement Siberian stone pine forest is much lower, and variability in the number of complete seeds is much higher than in taiga Siberian stone pine forest. When there are few filled seeds in a cone, the size of each of them increases. Therefore, the average weight of one filled seed is higher in the subsettlement Siberian stone pine forest than in the taiga forest. Thus, the quality of the cones in the years of average and especially high yield in the near-settlement Siberian stone pine forest is much lower, and the level of variability of the traits that characterise it is much higher, and the distribution of the traits is characterised by a pronounced negative kurtosis. Obviously, these peculiarities of the near-settlement Siberian stone pine forest are related to human interference in the course of its development, which disturbed the course of natural selection and deformed the genotypic composition of the population.

The structure of the reproductive function in four species and many geographic ecotypes of stone pines is studied on natural and experimental (clone archive and test progenies) objects. In Siberian stone pine in the south of the forest zone in Western Siberia, the dynamics of cone production is determined by weather conditions in the year of pollination. Seed productivity is declining due to late spring frosts and higher temperatures in September. Over the past 30 years, the directional change of these factors has determined a significant decline in cone production. The productivity and stability of the species and geographic ecotypes of stone pines is determined by the correspondence of their need for warmth to the climate of the test site. Under the conditions of climate change, the local ecotype in terms of growth and cone production is often inferior to more thermophilic species and ecotypes.

The hybridization zone on the northern border of the overlapping ranges at the junction of the Prilensky Plateau with the Stanovoy and Aldan highlands is studied using the analysis of the genotypes of adult plants of dwarf Siberian pine, Pinus pumila (Pall.) Regel, and Siberian stone pine, Pinus sibirica Du Tour, based on allozyme (nuclear codominant markers with biparental inheritance) and mtDNA data. We obtain evidence of modern hybridization of these species, as well as past hybridization events. Our study reveals that, in the conditions of Southern Yakutia, hybridization takes place mainly unidirectionally with an asymmetric flow of genes between species. The replacement of the mitochondrial genomes of Pinus sibirica with the genomes of Pinus pumila is noted in most of the studied samples from the sympatry zone. This phenomenon can be adaptive and contribute to the expansion of the distribution range of Siberian stone pine.

The genetic structure and differentiation of 12 Siberian dwarf pine populations from Chukotka, the Kamchatka Peninsula, Sakhalin Island and Kunashir Island were studied using 28 allozyme loci (Adh-1, Adh-2, Fdh, Fest-2, Gdh, Got-1, Got-2, Got-3, Idh-1, Lap-2, Lap-3, Mdh-1, Mdh-2, Mdh-3, Mdh-4, Mnr-1, Pepca, 6Pgd-2, 6Pgd-3, Pgi-1, Pgi-2, Pgm-1, Pgm-2, Skdh-1, Skdh-2, Sod-2, Sod-3, Sod-4). In total, 26 of the studied loci (92.9

Mutational witches’ broom (WB) is a local system of tree shoots with abnormally dense branching and slow growth that visually differs from the normal crown and is presumably caused by a dominant somatic mutation. In this study, we compared the growth of the mutant and normal clones from the same trees growing on different rootstocks and on different branches of the same rootstock to determine how a mutational WB affects a normal tree crown if they have the same starting position. We measured graft length, crown width, and stem diameter at the base of the graft in five pairs of 20-old mutant and normal clones originating from the same trees grafted on normal rootstock. The intrinsic capabilities of a witches’ broom are very limited. Single WB clones had 2.0–3.8-fold shorter stems, 1.5–2.0-fold lower crown width, and 1.2–2.0-fold lower stem diameter than single normal clones. When the mutant and normal clones grew together on a double-stem rootstock, mutant clones had approximately the same growth rate but easily suppressed normal crown clones. In this case, WB clones had 1.4–1.8-fold taller stem height, 3.0–4.0-fold higher crown width, and 2.5–4.0-fold higher stem diameter than normal crown clones due to the abnormally high attracting capacity of a WB. The more pronounced the specific traits in WB clones, such as reduced growth and increased branching, the more aggressive they behave relative to the normal crown to more quickly and strongly suppress growth. Characteristics of the WB, such as growth abnormality, aggressiveness relative to the normal crown, and reduced level of differentiation, make it more similar to a benign neoplasm.

The dynamics of Siberian stone pine sexual reproduction in the South-Eastern part of the West Siberian Plain was studied by 13-year stationary observations. The stand age was 160–180 years, the average tree height was 22 m, and the average diameter of the trunk at breast height was 53 cm. On average, 50–60 trees were analyzed annually (in different years from 25 to 100). Cones were counted and samples were collected annually from August 10 to August 20. The resercher (usually the author of this paper) climbed each tree, knocked down the cones with operating tools (a bat and a rod), and then their number was counted on the ground. A sample of 10–15 cones was taken from each tree. Afterwards, a complete morphological analysis was performed: the number of sterile and fertile scales, and underdeveloped and developed seeds were counted. Developed seeds were analyzed by the X-ray method. To determine the weight, only perfectly full seeds selected by the X-ray pattern were used. Information on weather conditions was used according to data from the Tomsk station of Roshydromet. The main factor in the cone initiation was the amount of precipitation during 2 years before the start of this process: with an increase in the amount of precipitation, the number of cones increases. However, the final seed productivity depends to a greater extent not on the number of initiated cones, but on the success of their further development. The most important stage in the cone development was spring in the year of pollination and the main negative factor was late frosts. The degree of their negative impact is determined by the sum of the effective (above 5 °C) mean daily temperatures at which the return of frost with temperature from –3 to –4 °C occurred. Complete abortion of cones occurred only when the sum of effective temperatures was 150–180 °C. The same frost at the accumulated temperature sum of 100–150 °C killed a significant part of the cones, and the rest strongly disrupted the development. When the sum of accumulated temperature was about 50 °C, a strong frost significantly increased the loss of seedbuds at all stages of their development, thereby reducing the number of full seeds. The average temperature of September in the pollination year was an important factor in seed production. The loss of seedbuds increased significantly with its increase. The only important trait that is formed in the year of cone maturity is the weight of full seeds: it increases with the amount of precipitation from April to June of the current year.

RUSSIAN JOURNAL OF FOREST SCIENCE, 2021, No. 5, P. 451–459 THE EFFECT OF THE AGE OF SIBERIAN PINE ON THE GROWTH AND MORPHOGENESIS OF VEGETATIVE PROGENY S.N. Velisevich, S.N. Goroshkevich Institute of Monitoring of Climatic and Ecological Systems SB RAS 10/3, Academichesky Ave., Tomsk 634055, Russian Federation. E-mail: velisevich@imces.ru Received 03 June 2021 The purpose of this work is to investigate the influence of the donor tree age on the variability of the morphological structure of shoots and crown using the example of 7-year vegetative progeny of Siberian stone pine trees of a wide age range. We analyzed clones of juvenile donor trees (j, 5-7 years old), immature (im, 28-56 years old), generative (g, 227-376 years old) and senile (s, 449-639 years old). The cuttings for grafts were sampled in the uneven-aged (5-700 years) stone pine forest (north of the Ob-Tom interfluve). Cuttings were grafted onto a uniform 5-year rootstock of local origin and planted at clone seed orchard. It was found that with increasing age of the donor tree, the number of lateral shoots and their length decreased, but the proportion of latent buds increased and their role in the formation of branching systems increased, the degree of dominance of the terminal shoot over the lateral shoots increased. The observed differences in growth and branching trends of grafts contributed to the formation of an age-specific habit of the grafts crown: juveniles slowly grew but actively branched, immature actively grew and actively branched, generative actively grew, but branched worse, senile equally poorly grew and branched. It has been suggested that the age of the donor tree determines, first of all, the character of grafts branching. Elongation of shoots presumably depends on the age of the donor tree, and on the influence of a young stock. Keywords: Siberian stone pine, Pinus sibirica Du Tour , age, graft, morphogenesis, growth. 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Рассмотрены мутационные «ведьмины метлы» -фрагменты кроны дерева с замедленным ростом, обильным ветвлением, сниженным апикальным доминированием и часто с обильным плодоношением.Мутация в целом негативно влияет на качество шишек и семян.На примере клонов из мутантной и нормальной частей кроны одних и тех же материнских деревьев показано, на каких стадиях развития семян повышаются потери у мутантов, а также сделаны заключения относительно их причин.Показано, что число семяпочек в шишках мутантных клонов в среднем в 1,4 раза меньше, чем у нормальных, семена у клонов «ведьминых метел» мельче, а их качество в целом хуже, чем у клонов из нормальной части кроны тех же деревьев.Установлены сниженное качество семян и низкая семенная продуктивность по сравнению с нормальными клонами у двух третьих частей мутантов, хотя отдельные клоны «ведьминых метел» были почти равны нормальным клонам по семенной продуктивности.Определено, что потери семян происходили по разным причинам и на разных стадиях развития, но у мутантов было значительно больше

The influence of scions donor tree age on the morphological variability of needles, shoots, and branching pattern was studied in 7-year-old grafted scions of Siberian stone pine (Pinus sibirica Du Tour). We analyzed clones of four age groups: seedlings (4–7 years), young trees (38–62 years), mature trees (238–376 years), and old trees (549–700 years). The results showed that during the first 7 years after grafting, the age of the scion donor tree greatly affects branching patterns and leaf morphology of grafted trees. The age of the scion donor tree also significantly affects the growth of grafts in length, albeit to a lesser extent. Grafts derived from seedlings, young, mature, and old trees had different ratios of shoot elongation and branching: weak growth and abundant branching, strong growth and abundant branching, strong growth and medium branching, weak growth and branching, respectively. The degree of needle xeromorphy, the level of apical dominance, and the number of epicormic buds increased significantly with the age of scion donor trees. Premature (late summer and autumn) growth of dormant buds was typical only for grafts derived from seedlings and, to a lesser extent, from young trees. The closer the scion donor tree is to the ontogenetic growth peak, the more elongated and abundant the branching of the grafts derived from it.

Carbon dioxide gas exchange and the pigment content of the photosynthetic apparatus of the Siberian stone pine Pinus sibirica Du Tour ecotypes vegetative scion from the West Siberian latitudinal transect grown on the geographical grafting plantation in the south of the Tomsk Region were studied. The latitudinal transect was represented by three ecotypes: Tomsk, the southern border of the range; Strezhevoy, middle taiga; Urengoy, northern border of the range. The age of the grafted trees was 20 years. It was shown that the photosynthesis intensity did not differ between ecotypes significantly, respiratory activity increased significantly from south to north, and the differences were 79 % between marginal ecotypes. The results of the experiment revealed that the respiration / photosynthesis ratio was twice as high in northern than in southern ecotype, which indicates a lower plant productivity of the northern ecotype. The results of measuring stomatal conductance and the intercellular CO2 concentration showed that these values did not differ between ecotypes significantly. Research has revealed the tendency towards the decrease of green pigment contents in the middle taiga ecotype and the significant decrease those in the northern ecotype. The Chl a/b ratio increased from south to north from 2.7 to 3.2. On the contrary, the Chl/Car ratio decreased between marginal ecotypes from 6.2 to 5.7 due to the reduce of green pigment contents in the northern ecotype. The obtained data indicate the photosynthetic acclimation when ecotypes were moved to the warmer climate. The photosynthetic pigment synthesis and respiratory activity are largely regulated by hereditary factors (the ecotype origin).

Mutational witches' brooms (WB) spontaneously arise in the tree crown. There are no male cones in Pinus sibirica WB and pollination always occurs with normal pollen. We studied 2-year-old seed progeny obtained from open-pollinated cones of WB and normal crown (NC) pines. There were significant morphological differences in two pairs of WB and NC families, while the third family pair studied showed barely pronounced differences. Segregation analysis of WB seed progeny based on needle length (growth trait) and total bud number (branching trait) revealed that about half of seedlings had a normal phenotype, while mutants were from 15.6 to 35.7 %. The rest seedlings could not be unambiguously identified, because they have not yet fully demonstrated the phenotype. Looking normal seedlings from WB families differed not only from mutants but also from NC progeny. Therefore, the mutation had some effect on both mutant seedlings and seedlings with a normal phenotype. Moreover, the denser was maternal WB the more differences were observed between WB and NC progeny.

The complete nucleotide sequence of Pinus sibirica Du Tour chloroplast genome (cp DNA) was determined in this study. The cpDNA was 116,635 bp in length, containing a pair of 473 bp inverted repeat (IR) regions (IRa and IRb), which were separated by large and small single-copy regions (LSC and SSC) of 63,908 and 51,781 bp, respectively. The cpDNA contained 113 genes, including 81 protein-coding genes, 4 ribosomal RNA genes, and 28 tRNA genes. The majority of these genes were single copy genes, while 4 genes existed as double copies, including 2 protein-coding genes (psbA and ycf2), 2 tRNA genes (trnAP and trnS). The overall GC content of P. sibirica cpDNA is 38.7%, while the corresponding values of the LSC, SSC, and IR regions are 38.0, 39.7, and 37.8%, respectively. The phylogenetic analysis confirmed clusterization of P. sibirica in Strobus subgenus.

Mutational witches’ broom represents a fragment of the tree crown with slower shoot growth, abnormally dense branching, decreased apical dominance and often with abundant cone-bearing compared with a normal crown. Mutational witches’ broom is a major source for the majority of ornamental dwarf conifer cultivars with abundant branching. Pinus sibirica is also capable of forming mutational witches’ brooms. The species has valuable edible seeds, and therefore, dwarf cultivars with abundant cone-bearing could be used to establish cone crop plantations. To reveal how the mutation causing witches’ broom affects the quality of cones and seeds, we carried out a comparative analysis of cone size, cone structure and seed quality in six grafted clones with witches’ broom and normal clones from the same trees, determining seed losses at the different developmental stages. Cones from mutant clones had 1.5–2.9 times smaller size than normal clones. Cones from 50% of the normal clones were more elongated in shape. In mutant clones, the numbers of fertile scales and ovules were 1.4 times lower than in normal clones. Seeds had a smaller size in all mutant clones, and seed quality and seed efficiency were lower in two-thirds of the clones compared with normal clones. Seed losses were observed at different developmental stages, but there were significantly more losses before pollination and during embryo development in mutants. Therefore, the majority of mutants had small cones and therefore a rather ornamental value because of reduced seed efficiency and small seeds. At the same time, individual mutant clones had a seed efficiency and the number of filled seeds close to those of normal clones. They could therefore be promising as cone-bearing cultivars for the commercial production of pine kernel.

Mutational witches' broom (WB) is a fragment of tree crown with abnormal morphogenesis, including slow growth, abundant branching, reduced apical dominance and often abundant seed production. Mutational WBs are the main source of ornamental dwarf grafting conifer cultivars. Siberian stone pine, like other conifers, is capable of forming mutational WBs. In order to reveal how the mutation affects the development of WB cones an analysis of the cone yield and cone size and structure in 20 WB clones was made, and they were compared with a mean normal Siberian stone pine cone with length 9 cm, width 6 cm, 57 seeds per cone and the proportion of the medial fertile zone 39.1-60.3% of the total number of scales. WB clones had a different number of cones. Thirteen-year old clones had 13 cones in average. All cone traits varied greatly among the WB clones. Three clones had shortest cones, their length was less than 3 cm. Two of the clones also had the smallest diameter, 2.3 and 2.2 cm, respectively. Four clones had relatively large cones, longer than 4 cm, and diameter 3.4 cm. The fertile zone in the cones of WB clones was from 27.8% to 55.6% from the total number of scales, i.e. only slightly smaller than that in normal cones. The cones contained 40-60 ovules, which gave rise to less than 20 seeds in 20% of the clones, and more than 40 seeds per cone in 15% of the clones. which is a third less than that in normal Siberian stone pine trees. The number of aborted seeds after pollination in cones was almost not high for all clones, however, for some, the proportion of aborted seeds was up to 30% of the total number of seeds per cone. Thus, the cones in WB clones were 2-3 times smaller, and they were generally inferior to normal Siberian stone pine cones, but the yield in WB clones was quite high. At the same time, the WB clones were highly variable in yield and cone quality. Only individual clones with good yield and relatively large cones can be promising for breeding as nut-bearing cultivars. Due to the negative WB crown density on the number and size of their cones. in most cases, the presence and abundance of cones can only serve as an additional feature that enhances the ornamental value of dwarf graft cultivars of Siberian stone pine. At the same time, all WB clones were fertile and could be used for cross-breeding and further selection work.

Inheritance of the age-specific traits of the Siberian stone pine crown structure by vegetative progeny was analyzed. Studies were carried out on 25-year-old grafts onto the same species seedlings as rootstocks. Scions for grafting were sampled from two groups of trees: young-mature (YM) and old growth (OG) trees in the southeast of the West Siberian Plain. The analysis of graft development showed that the YM trees had a significantly higher and thicker trunk, and their crowns were broader and denser due to a larger number of shoots. They multiplied by means of the branching feature due to the predominance of axes 2-3 branching orders. The OG trees formed small and transparent crowns that visually resembled separate branches from the upper parts of the crown of ontogenetically old trees. It was suggested that in the vegetative progeny of trees of a different ontogenetic state, the growth potential was epigenetically inherited.

The study was performed on 25-year-old grafted progeny of young and mature generative trees of the Siberian stone pine Pinus sibirica Du Tour. The Siberian stone pine forests in the south of Western Siberia, grafted on a young tree stock, the influence of the age of the mother tree on the vegetative and generative crown structure of the grafters and the degree of epigenetic inheritance of age- specific features of morphogenesis were studied. The analysis of the results showed that the differences between the grafting of young and mature trees according to the generative structure of the crown are expressed by an order less than in the vegetative structure. Ontogenetically, older grafts of mature trees with smaller crown sizes were superior to those of young trees due to the efficiency of generative processes in terms of the unit volume of the crown. According to the level of growth, which was estimated by the size of the stem and crown, they were significantly inferior to the grafts of young trees. The most interesting result is a noticeable difference in branching between the two groups of trees. The grafts of young trees were branched in accord with older axesformed mainly from the buds of regular renewal, due to which the total number of shoots in the crown increased substantially and, as a result, its density increased threefold. The share of latent buds in the grafts of mature trees increased substantially, and branching was developing mainly due to the first and second branching axes; as a result, the crowns of the grafting of mature trees visually resembled separate branches from the upper parts of the crown of ontogenetically old trees The results obtained imply that in the vegetative progeny of trees of a different ontogenetic state, the growth potential is primarily epigenetically inherited. Qualitative transformations in morphogenesis, including sexual reproduction, should be considered as secondary phenomena, as markers of epigenetic inheritance of growth potential.