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An analysis of hazel pollen seasons in Sosnowiec was presented on the basis of data from the years 1997–2007. The research was conducted by means of the volumetric method using a Burkard-type spore trap. The duration of pollen seasons was determined by means of the 98% method. The research demonstrated statistically significant correlations between the average, maximum and minimum temperature, relative humidity as well as the number of days with sub-zero temperature and the beginning of the hazel pollen season. It was demonstrated that the duration of the pollen season depended on air relative humidity, insolation and precipitation during the season and the annual sum depended on the weather conditions of the year preceding pollen production and also the weather conditions two years earlier. Significant correlations were also found between weather conditions and the daily concentration of pollen grains. The daily concentration decreased when relative humidity was high and increased with high insolation and air temperature.
This paper investigates pollen seasons for Corylus spp. and Alnus spp. for the years 1997-2007 in Sosnowiec, southern Poland. The research was conducted by means of the volumetric method using a Burkard-type spore trap. The duration of pollen seasons was determined by means of the 98% method. The aim of this study was to distinguish the types of the course of hazel and alder pollen seasons using cluster analysis, including non-hierarchical clustering of multi-feature objects – k-means clustering. The pollen seasons were divided into five types because of considerable variations from one year to another. For both taxons one dominant type was found, which was characterized by a very long period of compact pollen release with low values of the pollen count and by the occurrence of several maximums divided by periods of a lower pollen count. This work contains only a preliminary analysis on the types of pollen seasons because of relatively short data set. Future research on a larger series of measurements should be proved.
The influence of aphid feeding on chlorophyll a fluorescence in the leaves of four cultivated hazel cultivars, with different levels of resistance to filbert aphid (Myzocallis coryli Goetze), was studied. The maximum effect of photosystem reaction measured on dark-adapted hazel leaves (Fv/Fm parameter) and maximum efficiency of photon energy PAR conversion to chemical energy in light conditions (Y parameter) were estimated twice, in the leaves of four hazel cultivars with different levels of resistance to filbert aphid, using a fluorometer PAM- 2000 by Walz GmbH – Germany. The analysis of changes of these parameters showed that aphid feeding caused a reaction in all tested cultivars. The most visible reduction of the Fv/Fm and Y values as a result of aphid feeding was observed in the cultivars ‘Cud z Bollwiller’ and ‘Olbrzymi z Halle’, numerously colonized by aphids. A smaller number of aphids found on the leaves of more resistant cultivars – ‘Kataloński’ and ‘Lamberta Biały’, caused a weaker response of plants and a smaller decline in the value of this parameter. ‘Cud z Bollwiller’ cultivar showed higher tolerance than other tested cultivars to stress caused by the feeding of sucking insects. The Fv/Fm and Y parameters can be regarded as reliable indexes useful in diagnosing susceptibility of hazel cultivars to aphids, helpful in determining, for example, harmfulness thresholds.
Early spring flowering plants show large differences in the start dates of pollen emission due to high weather variability in the preceding period. In the present study, the influence of meteorological conditions on the start date of the hazel pollen season in Lublin in the years 2001-2009 was investigated. The aeropalynological study was carried out by the volumetric method using a Lanzoni VPPS 2000 sampler. The start of the hazel pollen season was determined using the 98% method. The differences in particular years of the study were over two months. Hazel pollen grains were recorded earliest in 2007, since from 13 January, and latest in 2003, from 18 March. It was found that accumulated 5-day mean temperature before the season affects the onset of the pollen season. As a result of multiple regression analysis, a statistical model was derived, which shows with great accuracy the relationship of the start of the hazel pollen season with total precipitation and the number of winter days.
Symptoms of pollen allergy in springtime in Middle and Northern Europe are mainly caused by pollen grains of birch, hazel and alder. The aim of the present study was the pollen fall comparison of the mentioned taxa in Lublin (Poland) and Skien (Norway). These sites are located approximately 1,200 km away apart by air. The pollen monitoring was carried out by gravimetric method in 1999-2000. The start and end of pollen seasons were defined by the 90% method. The beginning of pollen seasons for Corylus and Betula were observed 1-3 weeks earlier in Lublin than in Skien, but pollen grains of Alnus appeared simultaneously in both towns. In 1999, annual totals of Alnus, Corylus and Betula pollen grains were considerably less numerous in Skien than in Lublin. No important differences were observed among the pollen fall amounts of the mentioned taxa in 2000. The maximum values of pollen grains were defined in different terms. The results of investigations differed as regards the years compared as well as the sites.
The study was performed during two growing seasons (2002–2003). The experimental material was collected from hazel shrubs growing in three sites in Lublin. During the laboratory rearing that involved 1 922 larvae and pupae of 5 species of mining moths [Stigmella microtheriella (Stt.), Phyllonorycter coryli Nic., Phyllonorycter nicellii (Stt.), Parornix devoniella (Stt.), Coleophora serratella (L.)], 280 imagines of parasitoids were obtained. The most numerous group was Chalcidoidea f. Eulophidae – 93.2%, other species belonged to Braconidae –6.8%. The total parasitization of mining-moth larvae and pupae was 14.6%. The ratio of parasitization on mining moths for a particular complex of parasitoids oscillated from 7.8% to 41.2%. The highest parasitization ratio of mining moths was observed for the site II (16.3%) situated near a busy road.
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