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The present studies were conducted in 1999-2001 in three apple orchards differing from each other by the system of cultivation, the type of agricultural treatments and chemical control of pests. Their purpose was to monitor codling moth (Cydia pomonella L.) in different types of apple orchards using pheromone traps, finding out the relation between the occurrence of moths and the sum of effective temperatures as well as determining the number of wintering caterpillars of this species with the use of bands of corrugated paper. The analysis of male flight of codling moth on the basis of pheromone traps makes it possible to state the occurrence of two generations in each studied year. The maximum population of the first generation was observed in the second or third ten days of June, while that of the second generation in the first ten days of August. The moths flight began when the sum of effective temperatures was 109.2-145.2°C, and the mean diurnal temperature was 12.3-17.2°C.
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.
W pracy przedstawiono szacunkowe obliczenia ładunków Cd i Pb dostających się z nawozami fosforowymi i obornikiem do gleb użytków rolnych Polski dla poszczególnych województw w latach 1955-1995. Średni krajowy ładunek Cd pochodzący z rolnictwa w tym okresie wynosił 1,9 g‧ha⁻¹‧rok⁻¹ natomiast Pb 14,2 g‧ha⁻¹‧rok⁻¹. Podano także sumaryczny dopływ tych metali z rolnictwa i depozycji atmosferycznej w latach 1955-1987 oraz udział rolnictwa w całkowitym kumulatywnym ładunku. Głównym źródłem Pb wprowadzonego do gleb Polski był jego dopływ z atmosfery. W większości województw Polski południowej i południowo- zachodniej, udział kadmu pochodzącego z atmosfery dochodził do 90 a nawet i więcej procent całkowitego ładunku kumulatywnego tego pierwiastka dostającego się do gleby. W przypadku części Polski północno-wschodniej, centralnej i północnej więcej kadmu wprowadzonego do gleb pochodziło z rolnictwa niż z atmosfery.
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.
Studies on the population dynamics of aphids Cinara juniperi De Geer on the shrubs of Juniperus communis L. in the urban conditions of Lublin were conducted in the years 2002–2004 in two types of sites: a street one and a park one. The first individuals of this species were most frequently observed at the turn of April and May, while the maximum population was found in the first half of May. The course of the weather conditions affected the population dynamics of aphids. Those insects were observed in much bigger numbers on the shrubs growing in the street site. The preying of C. juniperi caused browning and drying out of the needles and inhibition of the stem growth, which had an influence on lower decorative character of the examined plants.
Gall-inducing insects may cause multiple physiological changes in host plants, such as the loss of photosynthetic pigments and reduced photosynthetic capacity. However, the direction of these changes is usually insect species-dependent. Therefore, the objective of this research was to characterize the indirect effects of galls induced by asexual generation of Neuroterus numismalis (Fourc.) and N. quercusbaccarum L. on photosynthesis by comparing changes in photosynthetic and photoprotective pigments and chlorophyll a fluorescence in foliar tissue with and without galls in naturally growing pedunculate oak trees (Quercus robur L.). The presence of galls of both Cynipidae species caused a significant decrease of chlorophyll a, b and carotenoids contents. Moreover, photosynthetic parameters (F0, Fm, Fv/Fm, Y, qP, qN) were significantly decreased. These results provide valuable information for diagnosing the oak infections using a noninvasive method, such as chlorophyll a fluorescence and predicting the effect of infections on photosynthetic productivity.
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