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The purpose of the studies was to observe the dynamics of number of Metopolophium dirhodum (Walk.) on rugosa rose, multiflowered rose, park rose cv. ‘Grandhotel’ and different varieties of border roses. Observations were conducted in four different sites in the green area of Lublin in the years 2001–2003. M. dirhodum was observed on all the analyzed roses. Annually this aphid colonized only the shrubs of rugosa rose and park rose ‘Grandhotel’ in all the sites. This is a host-alternating species, with the migration to the summer host of obligatory character (the colonies were observed in spring and autumn). The weather conditions had a significant effect on the date of the spring appearance and the autumn disappearance of aphids. The most numerous aphids were observed in the street site, while in the park one the population of this aphid was the lowest. Rosa rugosa was exceptionally willingly colonized by M. dirhodum. Those aphids occurred there in much higher numbers as compared with the other roses.
The aim of the study was to determine the level of threat by currant clearwing moth to black currant plantations in the vicinity of Lublin. Moth catches were performed using deltoid pheromone traps set, and the cane cutting methods were also used. Moths’ flight started at the end of May and lasted up to the first days of August. The flight dynamics was diversified on the particular plantations. The males’ catches and the cut shoots analysis showed that the economics threshold level was exceeded. The control of currant clearwing should be performed both on horticultural farms and amateur cultivations.
Studies concerning the occurrence of Anarsia lineatella on peach trees planting were carried out in the vicinity of Lublin in 2008–2009. Pheromone traps of Delta type were used to catch males. The study results revealed the presence of two generations of peach twig borer. The moth flight of particular generation was extended in time and lasted about one and a half month. Because of growing of peach and apricot cultivations, a large area of plum trees planting in our country and the possibility of occurrence of these pest on apple trees regular monitoring should be carried on.
Aphids are characterized by a specific morphology and show a high biotic potential. Most species have been described from the temperate regions of the world. The purpose of the present research was to investigate the biology, population dynamics and harmfulness of Phyllaphis fagi (L.) (Hemiptera: Aphididae: Phyllaphidinae) on Fagus sylvatica (L.) and its two varieties ‘Pendula’ and ‘Atropunicea’. Demographic parameters of this aphid were tested in field conditions. Trees as isolated elements of greenery in the urban environment were taken into the consideration. The highest density of overwintering eggs was observed in the bark crevices of forking shoots. The shortest prereproduction and reproduction periods and the highest fertility was exhibited in the second generation of aphids. Pre-reproduction and reproduction periods of successive aphids’ generations were extended while females’ fertility was reduced. Despite of varied number of aphids on F. sylvatica and its two varieties, no significant differences were stated. Feeding aphids caused leaves’ curling downwards on both sides of the mid-rib. Clear damage was visible even during the presence of few individuals on the leaf. Decorative values of trees were reduced as early as in June.
In the years 2003–2005 studies were conducted in the area of Lublin the aim of which was to study the population dynamics of aphids colonizing the trees of Juglans regia L. in the street and the park sites against the course of weather conditions. The weather in spring probably had no effect on the date of hatching of the larva of fundatrix, which was usually observed in the third 10-days’ period of May. On the other hand, the dry period, heat waves (above 30°C) and stormy rainfalls affected the break in the aphid population observed in July and August. The maximum population of P. juglandis was found in the second 10-days’ period of June, while that of Ch. juglandicola – at he turn of June and July. The highest number of P. juglandis was observed in 2004, while that of Ch. juglandicola in 2003. In 2003 the dominating species in both sites was Ch. juglandicola, while in the other years of studies it was P. juglandis.
It is commonly believed that gall inducers have the ability to control and program the host plant growth to their own benefit. The pattern of changes in the contents of reducing sugars, protein and phenolic compounds as well as the activity of chitinase and β-1,3-glucanase in galls, galled and intact leaves of Ulmus pumila were investigated during three stages of Tetraneura ulmi gall development. High protein accumulation in galls at the initial period of gall formation, increased biosynthesis of total phenolics during galling process, and the highest activity of pathogenesis-related protein at the stage of mature galls were detected. Therefore, it can be suggested that T. ulmi can manipulate the biochemical machinery of the galls for its own needs.
The choice of host plants by the phytophagous insects depends on a number of factors, including secondary metabolites which as “specific plant substances” have a significant influence not only on the physiology and behaviour of plant-eating insects but also on the chemism of plants’ defense. The present paper determined the effect of the feeding of Acrobasis advenella caterpillars on the content of flavonoids, phenolic acids and tannins in the inflorescences of two species of host plants, namely Aronia melanocarpa and Sorbus aucuparia. The content of flavonoids and phenolic acids in the extracts of both plants where caterpillars were feeding was lower as compared to the extracts from control plants. It was found out that the content of tannins in the plant material of S. aucuparia where caterpillars were feeding increased in comparison to the control material. In 2009, their content was found to be more than 1.5 times higher, reaching over 13% of DW. A reverse reaction was observed in the case of A. melanocarpa, where the content of tannins dropped significantly. The value of that parameter in 2009 decreased more than 1.5 times and it was 5.42% of DW, while in 2010 the decrease was 2-fold, reaching 2.61% of DW.
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