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Biological parameters of the onion thrips, Thrips tabaci Lindeman were studied on the following onion (Allium cepa L.) cultivars: Nasik Red Plus N-53, Onion Dr-301 (Krishna), Onion White, and Nasik Red, at 25±1oC and 65±5% RH. Signifi cant (p < 0.05) diff erences were found in the life stages and fertility life tables on diff erent cultivars except in the pupal stages. More information about the biological parameters of T. tabaci on onion cultivars can help in designing Integrated Pest Management programs for onion thrips.
An evaluation of the effect of four host plants on biological parameters of Maconellicoccus hirsutus and efficacy of Anagyrus kamali was conducted in the laboratory. Hibiscus rosa-sinensis and Hibiscus sabdariffa produced M. hirsutus with life cycles which were 1-2 days shorter than those of M. hirsutus reared on Solanum tuberosum, and Cucurbita pepo L. Egg to adult M. hirsutus survival was lowest in C. pepo (8.8%) and highest for H. sabdariffa (21.8%). C. pepo, H. rosa-sinensis and H. sabdariffa produced a more female biased M. hirsutus sex ratio from single ovisacs, than S. tuberosum. Although adult M. hirsutus females exhibited variation in size and longevity on the host plants tested, total fecundity was not significantly different. Life cycle of both sexes and offspring sex ratio of A. kamali emerging from M. hirsutus cultured on the four host plants were statistically similar. M. hirsutus infested H. rosa-sinensis and H. sabdariffa produced A. kamali with significantly higher fecundity (post emergence adult counts) and lower longevity compared to the other host plants. Females with largest femur (Mean length = 0.2950 ± 0.0053 mm) were produced by M. hirsutus infested H. rosa-sinensis. A. kamali efficacy measured by percent parasitization and percent adult eclosion was statistically similar for all M. hirsutus infested host plants tested.
The sweet potato whitefly, Bemisia tabaci (Genn.) (Biotype A: Hem.: Aleyrodidae) is one of the most important pests in Iran. The development of alternative methods that are not chemical applications, is necessary in pest management for the sake of human health and for the safety of the environment. In this research project, the effect of four herbal compounds Fumaria parviflora Lam. (Fumariaceae), Teucrium polium L. (Lamiaceae), Calotropis procera (Willd.) R. Br. (Asclepiadaceae), Thymus vulgaris L. (Lamiaceae) on the same biological parameters of cotton whitefly were compared with the insecticides azadirachtin and pymetrozin. The results showed significant differences between herbal compounds and insecticides on: egg longevity (F6, 39 = 2.96, p < 0.05), pupa longevity (F6, 37 = 4.49, p < 0.01) and adult longevity (F6, 31 = 4.47, p < 0.01); egg mortality (F6, 39 = 6.71, p < 0.001), total egg mortality (F6, 39 = 6.71, p < 0.001), sex ratio (female) (F6, 30 = 3.49, p < 0.01), oviposition period (F6,31 = 7.50, p < 0.001) and total fecundity/female (F6, 31 = 8.23, p < 0.001). These results indicated that a fumitory extract and pymetrozin had the best effect on longevity and mortality, respectively. According to the results, the fumitory had a noticeable effect on the different life stages of the sweet potato whitefly.
The quality of five commercial monocalcium phosphates (MCP) and dicalcium phosphates with natural admixtures of hydrated and dehydrated forms was assessed on the basis of their crystalline phases determined by roentgenographic irradiation, Ca and P contents, and solubility in water, 2% citric acid, 0.4% HCl, and ammonium citrate solutions. The phosphates were used in diets fed between days 1 and 35 of life to 300 Hubbard Flex male broilers, 6 replications (cages) of 10 chickens per treatment. Performance indices, Ca, P and Mg retention, and the concentration of these elements in blood and bone ash, as well as the physical parameters of femur and tibia bones were measured. The content of P in phosphates varied between 17.7% and 23%, their solubility in citric acid and HCl solutions ranged between 89–99%. The roentgenograms indicated that phosphate No. 1 contained pure MCP; No. 2, MCP with admixture of anhydrous dicalcium phosphate (DCP); No. 3, DCP with an admixture of MCP; No. 4, dicalcium phosphate dehydrate (DDCP); No. 5, DDCP with an admixture of DCP. The type of phosphate used in chicken diets did not influence body weight or feed intake. Phosphorous retention, Ca and P in serum, and some bone parameters were better in chickens fed the diet containing pure MCP (P<0.01). Lower concentrations of Ca and P in bones and worse parameters of bone elasticity were found in chickens fed diets containing DDCP with DCP. In the biological experiment, the overall best results were obtained in chickens fed diets containing pure hydrated monocalcium phosphate
In vitro coffee seedlings were exposed to an electromagnetic field (EMF) of 2 mT during 3 minutes in establishment, multiplication, and acclimazation phases. Shoot and root lengths and leaf pair numbers of treated groups increased when compared to control; in addition to SOD, CAT, and APX activities of in vitro-treated groups showed a decrease in levels. Four months after the magnetic treatment was applied, the same parameters were evaluated. Shoot lengths, root lengths, the pair of leaves numbers, and CAT activity increased in treated plants. APX activity decreased in treatment seedlings, whereas SOD activity did not show a difference between experimental groups.
The abundance of the spawning population of roach females from the coastal lakes Gardno (2 468 ha) and Łebsko (7 140 ha) located in the Słowiński National Park was estimated for the 1987-1992 period. Following bream, roach is the second most common cyprinid species in regulated fisheries catches. The size of the spawning population was estimated using Virtual Population Analysis and long-term fisheries statistics. Female roach dominated the exploited population at 62.4% in Lake Gardno and 64.3% in Lake Łebsko. During the analyzed period, more roach females were caught in Lake Gardno, which is more than twice as small as Lake Łebsko. Of the generations analyzed (1985, 1986, 1987, 1988, 1989 and 1990), more abundant years occurred in Lake Gardno. The most abundant generation in the two lakes was that of 1985, and following it, each subsequent generation was “weaker” than the preceding had been.
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A brief analysis of North Sea physics

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The current state of understanding the North Sea’s physical system is presented. First, basic phenomena like astronomical tides and general circulation will be described and analysed with respect to their physical nature and respective interactions. There will be special focus on fundamental dynamic balances. Next, some specific topics relevant to the marine ecosystem, the economy and society will be considered: among them, spreading and transport processes, the fresh water budget, the heat budget and storm surges. A separate section is dedicated to the North Sea of Tomorrow, i.e. the prospective variations of the physical environment resulting from global changes in future decades. The statements are based on the long experience of the authors and their groups and include findings that are little known if at all. The review finishes with a list of open questions and the corresponding research demands.
Many papers over recent years have demonstrated long-term temporal trends in biological parameters that can only be explained by global warming. I examined the long-term trends in the brood size of Starling (Sturnus vulgaris) in Mokrice area (north-western Croatia). I collected data from 1977 to 2007. To investigate the effect of spring temperatures on the brood size, local air temperature was used. The significant correlation (P <0.01) between mean brood size and the year (y = – 31.403 + 0.018x) indicates that brood size (mean number of nestlings per nest) increased by 0.018 nestling per year, or 0.54 nestling over the period of the study. Correlation between brood size (mean number of nestlings per nest) and mean spring temperature was also significant (P <0.05) and regression equation (y = 4.162 + 0.07x) indicates that brood size increased by 0.07 nestling per 1ºC. The correlation between mean spring air temperature and research year was significant (P <0.01). This data show that the mean May temperature has been increasing in the study area. We can conclude that Starlings in north-western Croatia are increasing their brood size and that the most likely cause is a long-term increase in spring temperatures.
W wodach pochodzących z dwudziestu jeden studni kopanych i wierconych oznaczono stężenia azotanów (V) i azotanów (III) oraz jonu amonowego. Stwierdzono, że pod względem stężenia związków azotu wody pochodzące z 58% badanych studni nie odpowiadają polskim normom.
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Estuaries of the Polish Baltic coastal zone

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Estuaries are dynamic ecosystems characterized by great and constant variability of physicochemical gradients and biological parameters. Considerable fluctuations in salinity levels, temperature, pH, concentrations of oxygen, nutrients and organic matter are quite natural in such water bodies. There are many estuarine forms at the Polish Baltic Coast, including open-sea gulfs (the Gulf of Gdansk and the Pomeranian Gulf), water bodies connected to the Baltic Sea (Lake Łebsko) and periodically closed water bodies connected to the Baltic Sea by channels or through river-mouths (Lake Jamno and Lake Gardno). The mouths of large rivers, like Odra and Vistula, also show features of estuaries. Estuaries perform a very important function of specific natural filters for a variety of chemical compounds contained in waters flowing through this area. In this way they form an effective buffer zone that prevents the penetration of toxic biological substances into seawater.
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