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In the studies on the metapopulation system two aspects are important: cognitive and practical. The former indicates that a metapopulation is a demographic structure of a higher level than coenotic or local populations and aims at recognition of relations between particular populations of a given species. The practical aspect reflects the issues of the dynamics and/or the extinction rate in particular populations and indicates potential habitats which can be colonized. The study of the Senecio rivularis metapopulation is created by relatively abundant population of ragwort in the Roztocze Highlands, Roztocze National Park, south-eastern Poland, recognized as the source population and three other called marginal or sink populations as well as potentially suitable habitats which are distributed as islands in adjacent hydrogenic areas. The distances between particular populations range from 1.3 to 6.5 km. As a long-lived, iteroparous rhizomatous clonal plant, insect-pollinated and anemochoric one, so having adaptations both for ‘escape in time’ and ‘escape in space’, S. rivularis may be treated as the model object of the study on the metapopulation level. The following hypotheses were put forward: (1) the spatial pattern, size and life-stage structures of particular populations reflect the time of their origin in the meta-system; (2) hydrochory is a complementary or alternative way of migration of anemochoric diaspores; (3) local watercourses and hydro-technical activity affect the formation and dynamics of S. rivularis metapopulation. The multi-aspect studies of the source population were conducted in the years 1987–2007. They aimed to establish the density, spatial pattern and life-stage structure of the S. rivularis population, both at a large scale, i.e. in the whole population (three times) and at a small scale, i.e. on the level of three particular clumps (four times). The size structure of generative genets and ramets in the whole population was elaborated five times. In the greatest of the other populations in the meta-system, the size structure was elaborated twice (2002, 2007) while the study of spatial and life-stage structures was done only once, in the first period, because of the disturbance of a greater part of the population in the next years. In the two remaining localities all plants were counted thanks to small abundance of the populations. Considerable changes in the spatial organization and life-stage structure of genets in the source and sink populations exhibited that colonization in the meta-system of S. rivularis proceeds in accordance with an island model of the ‘stepping stone’ type, downstream the river. Renaturalization of water relations of river catchment areas and construction of the so-called small retention objects affect the formation and dynamics of S. rivularis metapopulation which reflects at least some dynamics phases observed at the level of the source population: progressive, stable, fluctuation and/or regressive, and extinction phases. Knowledge of the density, life-stage and size structures of plants in a population facilitates a highly reliable determination of the development phase of a given local population in the meta-system and prognosis of its future.
Weather and climatic conditions may impact on many aspects of bird populations, including population size, the timing of breeding and synchrony between these variables in local populations. We examined synchrony in population size and the laying date of two starling Sturnus vulgaris populations 25 km apart, at Ohau and Belmont, in New Zealand. Data were collected in nest-boxes in both study plots from 1970 to 2003. Additionally we investigated possible relationships with a large geographical climate index, the El Niño Southern Oscillation (ENSO). Starlings at Ohau bred significantly earlier than at Belmont. The difference in the median of year median date of laying the first egg was 3 days. Simultaneously, the percent of nest boxes used by birds was much higher in Ohau (86%, SE = 4.1) than in Belmont (52%, SE = 2.9). However, we did not find a significant relationship between median dates of laying and the percent of nest boxes used by birds in each breeding season in the two populations. Furthermore, we found no influence of ENSO on (potential) synchrony in starlings’ breeding parameters. We suggest that lack of synchrony between two close local populations, both in percentage of occupied nest boxes and time of laying, is due to starlings responding to very local conditions, like food availability. We urge future studies to take advantage of spatially close populations.
Analysis of genetic diversity of 90 Vietnamese local-colored rice accessions was carried out using 40 SSR markers. The numbers of polymorphic alleles ranged from 3 to 12 alleles per locus and average of 7.1 alleles per locus. The similarity coefficients of the rice landraces fluctuated from 0.76 to 0.93; at a genetic correlation level of 0.78. Ninety accessions of rice landraces were divided into five groups based on analysis of genetic relationships. The results have indicated that 11 markers included M250, RM302, RM10926, RM208, RM227, RM17231, RM23251, RM5647, RM1376, RM339 and RM228 which gave the unique allele. These markers can be used effectively for genetic diversity of colored rice and provided a specific database and useful materials for landraces identification, local germplasm conservation for further colored rice improvement on rice quality via rice breeding programs in Vietnam.
Studies on amphibians of permanent water bodies and marshes in the Wawer district of Warsaw were carried out in the spring of 2007. This terrain is situated on the right bank of the Vistula River, and is one of the least urbanized areas of the city. In this study, species composition, frequency of occurrence and number of individuals on breeding sites were determined. Surprisingly, only six amphibian species were found, which was two times lower than found during previous research in the left bank area of Warsaw. The most common species occurring in Wawer were: moor frog (Rana arvalis) and common toad (Bufo bufo). Only 69.2 % of permanent water bodies were inhabited by any amphibian species. To enable future comparative studies to be made on the impact of urban development and increased human activity on local amphibian populations, the precise locality of breeding sites were provided.
W pracy oceniono zróżnicowanie genetyczne 28 południowopodlaskich populacji miejscowych Phaseolus vulgaris (fasoli zwyczajnej) zebranych podczas ekspedycji terenowych, przeprowadzonych w ciągu ostatnich 20 lat. Wykonano doświadczenia z zastosowaniem kombinacji 8 starterów EcoRI i 8 starterów Msel, w celu wybrania najlepszych kombinacji starterów do analiz AFLP. Rezultaty badań pozwoliły na wybranie 12 kombinacji starterów generujących największą liczbę polimorficznych prążków na żelach poliakrylamidowych. Otrzymane wyniki rozdziału fragmentów DNA posłużyły do określenia podobieństwa badanych obiektów metodą analizy skupień w oparciu o wartości współczynnika podobieństwa Jaccarda. Uzyskane wyniki wykazały przydatność metody AFLP do odróżnienie poszczególnych populacji Phaseolus vulgaris L. i określenie ich zróżnicowania wewnątrzpopulacyjnego.
In the present study, we used 37-year long dataset on Tawny Owls from the annual monitoring of nestboxes at a sample plot in Central Lithuania. We expected that Tawny Owls responded to changes in land use practices, stemming from a change in both political and economic system, which may affect prey abundance and composition, breeding performance and demography. To analyze temporal changes in monitored parameters, we divided the study period into three phases (1978-1989,1990-2001 and 2002-2014), corresponding to different socio-economic conditions. The number of nesting pairs of Tawny Owls decreased significantly in the last 13 years of the study, but the number of successful pairs fluctuated without any trend. The clutch size and number of nestlings varied without significant trends, but nesting success improved over the last 13 years. Annual apparent survival probability of the female Tawny Owls did not vary significantly over the study period (model averaged values between 0.71 and 0.73). Owls occupied nestboxes irrespective to the distance from the agricultural land during the first two study periods, but since early 2000s, owls tended to occupy nestboxes located deeper in the forest. Birds and small mammals were similarly important as prey items by biomass. Since the 1990s, the share of Microtus voles significantly decreased in the diet, while that of birds increased. In summary, changes in the diet, improved nesting success of the Tawny Owl and tendency of nesting in forest interior may indicate ongoing complex responses to the changes in environmental conditions.
W latach 2004-2007 przeprowadzono badania z 90 nowymi genotypami pszenicy jarej T. durum pozyskanymi z ICARDA w Aleppo. Są to populacje miejscowe pochodzące z Egiptu, głównie z prowincji Al Minya, El Giza, Suhaj i Sinai. Wszystkie genotypy poddano szczegółowej ocenie w czteroletnim cyklu doświadczeń polowych z uwzględnieniem takich cech, jak: odporność na wylęganie i choroby grzybowe, długość okresu wegetacji i ważniejszych podfaz, wysokość roślin, długość osadki kłosowej, liczba kłosków w kłosie, zbitość kłosa, liczba ziaren w kłosie i kłosku, masa ziaren z kłosa, masa 1000 ziaren oraz zawartość białka ogólnego w ziarnie. Stwierdzono duże zróżnicowanie badanego materiału pod względem wszystkich analizowanych cech, przy czym w odniesieniu do liczby ziaren w kłosie i kłosku, masy ziaren z kłosa oraz zawartości białka w ziarnie można sądzić o znacznej interakcji genotypowo-środowiskowej, o czym świadczą nieistotne bądź niskie współczynniki korelacji między latami. Dla przykładu można podać, że średnia masa ziaren z kłosa wynosiła w niekorzystnym 2007 roku 1,05 g, natomiast w 2006 r. - 1,54 g. Spośród analizowanej populacji można jednak wyodrębnić szereg interesujących genotypów mających stabilną i wysoką masę ziaren z kłosa, wysoki poziom białka w ziarnie oraz charakteryzujących się odpornością na wylęganie i choroby grzybowe. Genotypy takie mogą być interesującym źródłem pożądanych cech w praktycznej hodowli pszenicy twardej w Polsce.
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