PECULIARITIES OF SEA BUCKTHORN NATURALIZATION (HIPPOPHAE RHAMNOIDES L.) IN THE URALS

Успешная интродукция древесных растений сопровождается их натурализацией – внедрением видов инорайонного происхождения в природные фитоценозы. Примером натурализации древесных интроду- центов на Урале может быть образование популяций Hippophae rhamnoides L. на берегах озера Чебаркуль Челябинской области и в зольных отвалах Рефтинской ГРЭС Свердловской области. Высокая изменчивость однотипных признаков определяет приспособленность вида к меняющимся условиям среды и указывает на ослабление жесткости генотипического контроля, слабую стабилизацию фенотипа и увеличение роли внешних факторов в формировании фенотипического признака.Цель исследований – установление изменчивости плодов и листьев облепихи крушиновидной при на- турализации ценопопуляций облепихи на Южном и Среднем Урале в начале экспансии в 1999 г. и через 20 лет. Методикой работы предусмотрены маршрутное обследование интродукционных популяций облепихи на берегах озера Чебаркуль, золоотвалах Рефтинской ГРЭС и определение уровня изменчивости плодов и листьев форм, образованных при спонтанной гибридизации с начала натурализации облепихи и в на- стоящее время. Уровень изменчивости морфологических признаков оценивался по эмпирической шкале уровней изменчивости С. А. Мамаева. В чебаркульской и рефтинской популяциях преобладают плоды облепихи с овальной, шаровидной и конусовидной формой с желтой, светло-оранжевой, оранжевой, красно-оранжевой окраской. По массе 100 шт. плодов наибольшее хозяйственное значение имеют формы чебаркульской популяции, отобранные в начале расселения облепихи на берегах обмелевшего озера Чебаркуль. Посевом семян от свободного опыления нами получен ряд перспективных форм с массой 100 шт. плодов от 40,9 до 70,2 г. Некоторые чебаркульские формы облепихи не уступают по данному признаку сортам этой культуры. Отбор крупноплодных форм облепихи стал возможен в начале плодоношения чебаркульской облепихи. Натурализация данной культуры происходит за счет микроэволюционных процессов в интродукционных популяциях и формообразования за пределами естественного ареала. The successful introduction of woody plants is accompanied by their naturalization – the introduction of species of foreign origin into natural phytocenoses. The population’s formation of Hippophae rhamnoides L. on the shores of Lake Chebarkul in the Chelyabinsk region and ash dumps of the Reftinskaya SDPP in the Sverdlovsk region can be an example of the naturalization of tree introduced species in the Urals.The high variability of the same type of traits determines the species adaptability to changing environmental conditions and indicates a weakening of the genotypic control rigidity, weak stabilization of the phenotype and an increase in the external factors’ role in the formation of the phenotypic trait.The purpose of the research is to establish the variability of fruits and leaves of sea buckthorn during naturalization of sea buckthorn cenopopulations in the South and Middle Urals at the beginning of expansion in 1999 and 20 years later.The methodology of the work provides for a route survey of the introduction populations of sea buckthorn on the shores of Lake Chebarkul, ash dumps of Reftinskaya SDPP and determination of the level of variability of fruits and leaves of forms formed during spontaneous hybridization from the beginning of naturalization of sea buckthorn and at present time. The level of morphological traits’ variability was assessed using an empirical scale of levels of variability by S.A. Mamaev. In the Chebarkul and Reftinskaya populations sea buckthorn fruits with an oval, spherical and conical shape, with a yellow, light orange, orange, red-orange color prevail. By the mass of 100 pieces of fruits, the forms of the Chebarkul population, selected at the beginning of the resettlement of sea buckthorn on the shores of the shallow lake Chebarkul, are of the greatest economic importance. By sowing seeds from free pollination, we obtained a number of perspective forms with a mass of 100 fruits from 40.9 g to 70.2 g. Some Chebarkul forms of sea buckthorn are not inferior to the varieties of this crop in this respect. Selection of large-fruited forms of sea buckthorn became possible at the beginning of fruiting of the Chebarkul sea buckthorn. Naturalization of this culture occurs due to microevolutionary processes in introduction populations and morphogenesis outside the natural area.

Macrophage polarization is linked to Ca2+-independent phospholipase A2β-derived lipids and cross-cell signaling in mice

Phospholipases A2 (PLA2s) catalyze hydrolysis of the sn-2 substituent from glycerophospholipids to yield a free fatty acid (i.e., arachidonic acid), which can be metabolized to pro- or anti-inflammatory eicosanoids. Macrophages modulate inflammatory responses and are affected by Ca2+-independent phospholipase A2 (PLA2)β (iPLA2β). Here, we assessed the link between iPLA2β-derived lipids (iDLs) and macrophage polarization. Macrophages from WT and KO (iPLA2β−/−) mice were classically M1 pro-inflammatory phenotype activated or alternatively M2 anti-inflammatory phenotype activated, and eicosanoid production was determined by ultra-performance LC ESI-MS/MS. As a genotypic control, we performed similar analyses on macrophages from RIP.iPLA2β.Tg mice with selective iPLA2β overexpression in β-cells. Compared with WT, generation of select pro-inflammatory prostaglandins (PGs) was lower in iPLA2β−/−, and that of a specialized pro-resolving lipid mediator (SPM), resolvin D2, was higher; both changes are consistent with the M2 phenotype. Conversely, macrophages from RIP.iPLA2β.Tg mice exhibited an opposite landscape, one associated with the M1 phenotype: namely, increased production of pro-inflammatory eicosanoids (6-keto PGF1α, PGE2, leukotriene B4) and decreased ability to generate resolvin D2. These changes were not linked with secretory PLA2 or cytosolic PLA2α or with leakage of the transgene. Thus, we report previously unidentified links between select iPLA2β-derived eicosanoids, an SPM, and macrophage polarization. Importantly, our findings reveal for the first time that β-cell iPLA2β-derived signaling can predispose macrophage responses. These findings suggest that iDLs play critical roles in macrophage polarization, and we posit that they could be targeted therapeutically to counter inflammation-based disorders.

Variation in cone morphology and seed characters in Pinus strobus in Quebec

To investigate the patterns of variation in white pine (Pinus strobus L.), 10 natural populations from Quebec were compared using the phenotypic variation of cone and seed traits. Eight characters were measured on 10 cones collected from 30 trees in each of the 10 sampled populations. Four populations were from the Ottawa River region and four from the St. Lawrence Lowlands region, while two populations were at the margin of the natural range of the species in Quebec, from the Abitibi region and Anticosti Island. Significant differences among populations were detected for each character. Estimates of repeatability of these traits were relatively high, suggesting substantial genotypic control over them. These estimates were consistent from population to population. Results of multivariate analyses suggest that populations from the Ottawa River region are similar to those from the St. Lawrence region, with populations from these regions diverging only in cone scale length. However, populations from the St. Lawrence region were more distinct from each other than those from the Ottawa River region. The population from Abitibi deviates considerably from the other populations, suggesting habitat-selection pressures acting at the margin of the natural range of the species under continental conditions. Finally, no general geographical trend was detected in the observed variation. Key words: white pine, morphology, cone, seed, variation.