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1.
The loreyi leaf worm,Mythimna (Acantholeucania) loreyi Duponchel (Lepidoptera, Noctuidae), is a pest of gramineous crops and causes significant economic damage to maize. In field
surveys on maize to determine the parasitoid community and its impact on the pest in the eastern Mediterranean region of Turkey,
nine parasitoid species were found associated with immature stages ofM. loreyi: The hymenopteran (Braconidae and Ichneumonidae) parasitoidsCotesia (=Apanteles) ruficrus (Haliday),Chelonus oculator Panzer,Meteorus ictericus Nees,Hyposoter didymator (Thunberg),Sinophorus sp.; and the dipteran (Tachinidae) parasitoidsPseudogonia rufifrons Wiedeman,Exorista rossica Mesnil,Gonia picea (Robineau-Desvoidy) andLinnaemya vulpina (Fallen) — the last three recorded for the first time as parasitoids ofM. loreyi in Turkey.C. ruficrus was the dominant parasitoid species, being recovered from 38.5% of the larvae collected and was also the most prevalent species,
existing in 91.0% of the fields in whichM. loreyi was found. Total parasitism levels achieved by braconid species was 41.4%, by ichneumonid parasitoids 4.8%, and by tachinid
parasitoids 1.9%. In a separate field experiment, seasonal population fluctuations and natural efficiency ofC. ruficrus onM. loreyi were found to be 35.1% and 42.4%, respectively. Population levels ofC. ruficrus were closely related to fluctuations in the population ofM. loreyi, with parasitism ranging between 0 and 77.3% during the study.
http://www.phytoparasitica.org posting Aug. 28, 2005. 相似文献
2.
Weed control, an important practice in agroecosystems to protect crop production, is usually achieved with herbicides. However,
these pesticides are expensive, pose potential risks to the environment, may affect some beneficial organisms indirectly,
and decrease overall arthropod biodiversity, including pests and their natural enemies, by removing weeds that might act as
hosts or shelters for many organisms. The activity density response of important surface-dwelling arthropod predators (ground
beetles [Coleoptera: Carabidae], ants [Hymenoptera: Formicidae] and spiders [Arachnida: Araneae]) to herbicides (trifluralin
and paraquat), and to two alternative weed management practices (rye straw mulch and mechanical treatment to maintain weeds
below threshold levels, in comparison with an untreated check), was assessed using pitfall traps. The mulch treatment had
the greatest effect on activity density, reducing the number of predators trapped significantly (P<0.05). Herbicide use resulted in significant (P<0.05) reductions in the activity density of ground beetles. Most predators were trapped in the check plots — which had the
highest weed biomass, followed in turn by numbers trapped in the threshold weed control treatment, the full herbicide application
and the mulch treatment plots.
http://www.phytoparasitica.org posting July 10, 2002. 相似文献
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4.
Grown as a monoculture, peas (Pisum sativum L.) exhibit severe lodging after flowering and lodging causes yield reductions considerable. This study was conducted to investigate the effects of dose (untreated, 25, 50, 75 and 100 g a.i. ha?1) and stage (late vegetative, early blooming and early pod filling) of mepiquat chloride (MC) application on the growth, lodging control, seed yield and yield parameters of pea (Pisum sativum L.) under field conditions in Erzurum, Turkey in 2002 and 2003. Application doses of 25, 50, 75 and 100 g a.i. ha?1 significantly reduced stem height by 5.3 %, 7.2 %, 7.5 % and 6.4 % and increased stem width by 7.5 %, 12.7 %, 12.3 % and 15.7 % respectively, when compared with the untreated control, and thereby reduced the tendency of the crop to lodging. Increases of the seed yield under different application doses of MC ranged between 13.7 % and 20.1 % over the untreated control. However, in all parameters investigated, except for stem width, higher application doses of MC gave no clear advantages compared with the application dose of 25 g a.i. ha?1. Seed yield was also significantly influenced by application stage of MC and application at early blooming stage of crop, MC significantly increased seed yield by 11.4 % and 10.2 % when compared with the late vegetative and the early pod filling stages respectively. Furthermore, the interaction of application dose and stage was significant, and spraying of pea plants with 25 g a.i. ha?1 MC at early blooming stage has the most beneficial effects on the characters evaluated. 相似文献
5.
Zinnur Gozubuyuk Mesut Cemal Adiguzel Erdal Dasci 《Archives of Agronomy and Soil Science》2020,66(12):1611-1626
ABSTRACT Energy requirement increases rapidly in agriculture due to the increase in mechanization. The aim of the present study is to evaluate the energy use efficiency of silage maize under three different tillage practices (conventional, reduced, no-tillage) combined with four different irrigation levels (full and three deficit irrigations). The no-tillage and reduced tillage practices provided savings in input energy at the rate of 17.4 and 9.1%, respectively compared to the conventional tillage. The highest silage yields in all irrigation levels were obtained in the no-tillage practice. Therefore, in full and deficit irrigated silage maize, the highest energy ratio, energy productivity and net energy and the lowest specific energy values were manifested in the no-tillage practice. Energy rates in the no-tillage practice were higher by 34.2 and 22.9% than the conventional and the reduced tillage practices, respectively. Moreover, the direct and non-renewable energy requirements were the lowest in the no-tillage practice. In conclusion, the fully-irrigated no-tillage practice can be recommended to obtain the highest energy use ratio and productivity. However, no-tillage irrigated with up to 50% less water amount could be a better alternative for areas with a water shortage by improving the energy use ratio with better water and fuel savings. 相似文献
6.
Fidan I Yesilyurt E Gurelik FC Erdal B Imir T 《Comparative immunology, microbiology and infectious diseases》2008,31(6):467-475
Salmonella typhi (S. typhi) is an important pathogen which causes typhoid fever. The cytokines released from the macrophages, playing a role in the host defense against Salmonella infection, are crucial in the defense against the infection. IFN-γ provides a protection against Salmonella infection by developing macrophage activation in different mechanisms. This study was designed to investigate the effect of the recombinant IFN-γ (rIFN-γ) on the cytokines secreted from S. typhi stimulated macrophages. Macrophage isolation was done in the heparinized blood samples obtained from healthy people, and following the priming with rIFN-γ for 72 h the cells were stimulated by S. typhi and then the cytokine levels in culture supernatants were determined by enzyme-linked immunosorbent assay. It was observed that rIFN-γ reversely increased the levels of IL-1, IL-2 the levels of which were decreased by S. typhi and that it increased TNF-α levels while suppressing the levels of antiinflammatory cytokines such as IL-10 and TGF-β the levels of which were increased by S. typhi. Consequently, rIFN was observed to increase protective Th1 response by affecting the secretion of cytokine during S. typhi infection and it was considered to be a good target especially to prevent and treat invasive Salmonella infections. 相似文献
7.
Study aims to investigate the effects of vermicomposts containing oil processing wastes, dairy manure, municipal open market wastes and straw on the growth, nutrient concentrations and nutrient uptakes of corn plant. For this, there different mixtures were prepared. Vermicomposts were applied with the rates of 0, 5000, 10000, and 20000 kg ha?1 to 2 kg soil containing pots. Study was conducted in growth chamber for 2 months. Vermicompost applications increased plant growth, some plant nutrient concentrations and uptake. Also, vermicomposts showed the variation on parameters depending on their mixtures. Results showed that nutrients taken by the plant increased with the vermicompost until 10000 kg ha?1 dose. Most of the nutrient concentrations such as phosphorus, potassium, calcium, magnesium, iron, and manganese (P, K, Ca, Mg, Fe, and Mn) were not increased in plant tissues, whereas uptake of them by the plant showed a significant increase. In addition, residual soil nutrients increased with the increase in vermicompost levels. 相似文献
8.
The effects of environmental enrichment and transport stress on the weights of lymphoid organs,cell‐mediated immune response,heterophil functions and antibody production in laying hens 
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下载免费PDF全文 Erdal Matur İbrahim Akyazi Evren Eraslan Elif Ergul Ekiz Hüseyin Eseceli Mehmet Keten Kemal Metiner Deniz Aktaran Bala 《Animal Science Journal》2016,87(2):284-292
The effects of environmental enrichment and transport stress on the immune system were investigated in laying hens. A total of 48 1‐day‐old chickens were used, half of the chickens were reared in conventional cages (RCC) and the rest in enriched cages (REC). Transport stress was applied in the 17th week. Liver weight decreased, spleen and bursa of Fabricius weights, white blood cell count, CD4+ and CD8+ cell proportions increased due to the transport. Environmental enrichment significantly increased antibody production and tended to increase monocyte percentage and CD8+ cell proportion. The effect of transport on, heterophil (H) and lymphocyte (L) percentages was not significant in RCC chickens. While heterophil percentage and H:L ratio increased, lymphocyte percentage decreased in REC chickens subjected to transport. Transport stress increased heterophil functions both in REC and RCC chickens, but the increase was higher in REC hens than in RCC hens. In conclusion, although environmental enrichment did not neutralize the effect of transport on lymphoid organs, it activated the non‐specific immune system, cellular and the humoral branches of the specific immune system by increasing heterophil functions, CD8+ cells and antibody production, respectively. Therefore, environmental enrichment suggested for improving animal welfare may also be beneficial to improve the immune system of birds exposed to stress. 相似文献
9.
Davidson JM Ondrak JD Anderson AA Swinford AK Erol E 《Journal of the American Veterinary Medical Association》2011,239(12):1589-1593
10.
In the study, the effects of different training systems (Steep Leader: SL, Spanish Bush: SB and Vogel Central Leader: VCL) on quality properties and bioactive components of “0900 Ziraat” sweet cherry fruit (Prunus avium L.) were investigated. The size, color and firmness values of the fruit varied depending on training system. The largest fruit was obtained in the SB training system. The fruit on trees trained VCL and SB had higher firmness than the fruit of trees trained SL. The color values of the fruit of VCL were higher than the other systems, while the vitamin C content was lower. The lowest acidity and soluble solids content (SSC) were measured in fruit trees trained SL. The highest values for bioactive compounds as phenolics, flavonoids were measured in fruit of SL training system. In the sweet cherry fruit, the major phenolic acid was catechin. The catechin, rutin, caffeic acid, 4?hydroxybenzoic acid, 4?aminobenzoic acid and transferulic acid content of the fruit in the SL training system were higher than those of SB and VCL. As a result, it was revealed that there is an effect of the training system on fruit quality; SB training system had higher values in terms of fruit size, whereas in terms of bioactive compound content, SL training system had higher values.
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