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Genetic Diversity in Salix gordejevii Populations from Different Environmental Gradients in Horqin Sandy Land, Northern China

Huang Wen-Da, Zhao Xue-Yong, Zhao Xin, Luo Ya-Yong, Feng Jing, Su Na, He Yuan-Zheng

Polish Journal of Ecology

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2019

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Vol. 67, nr 3

175--185

EN

Salix gordejevii (Salicaceae) is a climax and dominant sand-fixing shrub species native to the northern China. We assessed S. gordejevii population genetic variation in different environmental gradients in Horqin Sandy Land, Northern China using inter-simple sequence repeat (ISSR) markers, and investigated the possible existence of relationships between genetic diversity and environmental gradients. The results showed that S. gordejevii populations in general have high genetic diversity. An analysis of molecular variation (AMOVA) revealed relatively high levels (> 89.91%) of within-population genetic variation. Based on cluster analysis, the 12 studied S. gordejevii populations can be clustered into three clades. Genetic diversity and differentiation of S. gordejevii populations are affected from different environmental gradients. Genetic diversity of all populations was affected by habitat environment change, and was well-correlated with the humidity gradients. These results have important implications for restoration and management of degraded ecosystems in arid and semi-arid areas.

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Assessment of Chosen Reproductive Cycle Processes and Genetic Diversity of Salix myrtilloides L. in Wetlands of Polesie Lubelskie: The Prospects of Its Survival in the Region

Pogorzelec M., Głębocka K., Hawrylak-Nowak B., Bronowicka-Mielniczuk U.

Polish Journal of Ecology

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2015

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Vol. 63, nr 3

352--364

EN

Salix myrtilloides L. is an endangered species whose western limit of range runs through Poland. The main aim of the study was to increase the knowledge on the ecology and biology of S. myrtilloides populations in the Polesie Lubelskie region (Eastern Poland) in order to create an effective protection program. An 80% decrease in its population was found in this area. Our study was conducted to identify the mechanisms responsible for the process of withdrawal of this species from its natural stands by determining whether the processes of generative reproduction (pollen viability and germinability, seed germination ability and dynamics) in the populations occur properly and by characterizing within- and among-population genetic diversity of S. myrtilloides, using ISSR (Inter-Simple Sequence Repeat) primers. The results confirmed that S. myrtilloides pollen viability was high (84.17±8.67), and so were the seed germination ability (76% of the total number of sown seeds/24 h) and dynamics. The within-population genetic diversity was quite high for this species and the inter-population genetic variation was of medium value (ΦPT=0.148). The condition of two populations, their genetic diversity and sex ratio as well as the correctness of the investigated reproductive cycle stages altogether give prospects for their survival. It seems to be very important to start conservation involving the reintroduction and reconstruction of S. myrtilloides populations in the Polesie Lubelskie region. The proposed method for restoration of S. myrtilloides resources would be possible if ex situ cultivation and in vitro methods were used.

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Success of wild pear Pyrus pyraster (L.) Burgsd. in colonization of steep sunny slopes : an interdisciplinary study in the Bielinek Reserve (NW Poland)

Antkowiak W., Cedro A., Prajs B., Wolko Ł., Michalak M.

Polish Journal of Ecology

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2012

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Vol. 60, nr 1

57-78

EN

A local population of Pyrus pyraster was studied in dry and warm habitats: xerothermic grasslands Potentillo-Stipetum capillatae and Adonido-Brachypodietum, as well as thermophilous oak forest Quercetum pubescentipetraeae in the forest-steppe Bielinek Reserve (NW Poland). Our aims were to assess: (1) the ability of this species to adapt to extremely dry sites, as a pioneer woody plant; (2) its phytosociological position; and (3) morphological variation and genetic diversity of the local population. The pear trees in Bielinek Reserve seem to reach an optimum in shrub communities of the class Rhamno-Prunetea, but tree age clearly indicates that the grasslands were colonized by wild pear trees already before the shrub communities developed. This indicates that P. pyraster can colonize very dry, eroded sites, such as steep sunny slopes covered by xerothermic grasslands. Wild pear trees form plant communities that are a seral stage followed by forest-shrub communities or thermophilous forests. The species in xerothermic shrub communities of the reserve shows a high constancy. It is also very resistant to extreme temperatures, insolation, drought, and erosion. Its tree-ring width (on average 1.1 mm per year) was strongly related to precipitation and temperature in spring and summer. High precipitation resulted in wider tree rings, while dry years (associated with high air temperature) caused a decrease in tree-ring width. Another significant factor is precipitation in winter, which had a positive influence on tree-ring width. Microsatellite markers revealed a high level of genetic diversity in this population. Our results suggest that wild pear can be recommended for afforestation of areas affected by droughts and disturbed sites in Central Europe. It can be used to increase the heterogeneity of the landscape, e.g. by creation of forest ecotones and for planting along roads and field margins, especially considering the predicted climate change.

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Genetic diversity of populations of Brachypodium pinnatum (L.) P. Beauv. : expansive grass in a fragmented landscape

Bąba W., Kurowska M., Kompała-Bąba A., Wilczek A., Długosz J., Szarejko I.

Polish Journal of Ecology

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2012

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Vol. 60, nr 1

31-40

EN

Brachypodium pinnatum belongs to native grasses which could dramatically decrease the biodiversity of calcareous grasslands, therefore, an examination of the mechanisms of its expansion is of prime importance for their conservation. We studied the genetic structure of 12 subpopulations of the expansive grass B. pinnatum in a heterogeneous landscape with AFLP markers, aiming at determination whether spatial isolation influences the genetic diversity and the population genetic structure of this species. A high level of overall (79%) and within population polymorphic loci (38.44%) were found and 220 different genotypes were distinguished among the 252 samples analysed. No significant population structure nor isolation-bydistance were found, despite their long-time fragmentation history. This confirms that isolation of calcareous grasslands in a landscape cannot prevent the expansion of B. pinnatum grasses because of the high generative dispersal ability. Subsequent quick and extensive clonal growth of this species enables the successful establishment. In most cases mowing or grazing is sufficient to keep this species at a low density within ancient grasslands and to prevent seed and pollen dispersal, but not for restoration of species-rich calcareous grasslands.

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Demographic versus genetic (RAPD) variation between and without two populations of the clonal plant Paris quadrifolia L. (Liliaceae)

Kosiński I., Stefanowicz-Hajduk J., Ochocka R.

Polish Journal of Ecology

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2009

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Vol. 57, nr 2

303-311

EN

The two populations of Paris quadrifolia L. were studied in isolated habitats in a currently fragmented landscape. Both populations were located in deciduous forests, the first (A) - on fresh mineral and acidic soil, and the second (B) - on wet organogenic, less acidic and more fertile soil. We hypothesized that genetic variation should be higher within population of more fecund plants, and that genetic distance between the two populations that occupy different isolated habitats in a fragmented landscape should be high. Demographic characteristics of populations were studied in the 2000-2005 period. In patches of both populations, 22 permanent plots measuring 1m[^2] each were designated. For molecular testing 41 samples from both populations were selected. The share of generative shoots was higher in the population A than population B (0.35 and 0.20, respectively). However, the fecundity of ramets expressed as the number of seeds in the ripe fruit was lower in A than in the B population (15 versus 21 seeds). The germination ability was significantly higher for the seeds from A than from the B population (79% versus 44%). The survival of the juveniles was high in both populations (54 and 76%). The Random Amplified Polymorphic DNA (RAPD) analysis with the application of five primers permitted identifying 91 loci. The estimation of genetic diversity was based on polymorphic loci, the share of which was average 44%. Nei.s gene diversity (h) was higher in the A than B population (0.28 versus 0.22). The genetic diversity between the populations was not large (G[ST] = 0.14). Clonal diversity was very high, G/N ratio = 1, and cluster analysis showed intermingling between samples from both the populations. There were quite a small genetic distance (D = 0.10), and a rather high level of gene flow (Nm = 1.51) between the populations from currently isolated habitats. The obtained results indicate that the genetic diversity was lower within population of more fecund plants from more productive habitat.

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Zachowanie różnorodności biologicznej

Kośmicki E.

Przegląd Komunalny

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2003

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nr 4

21-21

PL

Różnorodność biologiczna należy do najważniejszych koncepcji ochrony przyrody, a także trwałego i zrównoważonego rozwoju. Pojęcie to stało się szeroko znane dopiero po Szczycie Ziemi w Rio de Janeiro (1992), kiedy to podpisano Konwencję o biologicznej różnorodności (Convention on Biological Diversity). Od tego czasu pojęcie to dotyczy biologicznej różnorodności istniejących gatunków biologicznych, różnorodności ekosystemów, czy wreszcie różnorodności genetycznej w obrębie określonego gatunku.