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《Bioscience, biotechnology, and biochemistry》2013,77(8):2199-2202
Three hundred sixty-six Aspergillus strains preserved at the National Institute of Technology and Evaluation (NITE) were compared as to phylogenetic relationships (11 species-clusters) based on the DNA sequences of the D1/D2 domains of LSU rRNA and ITS regions, including the 5.8S rRNA and biological activities of their secondary metabolites. The results showed relatively well correlation between the phylogenetic distribution and the production of bioactive compounds, especially, antimicrobial activities. 相似文献
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A field study was carried out for 6 wks to assess, from both an efficiency and economic perspective, the effect of individual and integrated success of feeding and topical applications of two formulations of Bacillus thuringiensis var. israelensis (Bti) in controlling house fly (Musca domestica L.) larvae and adults in poultry houses. There was no significant difference between the 1 g and 2 g L?1 spray applications of Bti. In the absence of spray applications, no significant differences in larval mortalities were observed between the 250 mg and 500 mg kg?1 feed applications. The percentage mortality of larvae accomplished as a result of using a combination of 250 mg kg?1Bti feed and 2 g L?1 spray applications was equivalent to that obtained as a result of combining 500 mg kg?1Bti and 1g L?1 spray applications. Treatment with Bti caused significant reductions in the emergence (up to 74%) of house fly adults compared to the control. The fact that the emergence of adult house flies was affected by Bti treatments implies that Bti has sublethal effects on house fly larvae. The cost–benefit analysis (expressed in terms of mortality of larvae growing) indicated that the most effective combination for house fly larvae and adult house fly emergence control was the 500 mg kg?1 of feed and 2 g L?1 spray application combination that resulted in 67% larval mortality and a 74% decrease in adult house fly emergence. This study presents commercial users with various alternatives for possible combinations of the two Bti formulations. 相似文献
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We evaluated the performance of Coptera haywardi (Ogloblin) (Diapriidae) and Pachycrepoideus vindemiae (Rondani) (Pteromalidae), both hymenopteran pupal parasitoids of Anastrepha spp. (Diptera: Tephritidae). Performance was studied by manipulating the following environmental conditions in the laboratory: (1) soil type, (2) soil moisture content, (3) soil compaction, and (4) depth at which pupae were buried in the soil. There were two experiments: in the first, exposure time of pupae was held constant and in the second, it varied. In the first experiment, C. haywardi was significantly more effective than P. vindemiae in parasitizing fly pupae. With exposure time held constant (36 h), only soil type and pupal burial depth were significantly related to parasitism rates. While P. vindemiae only parasitized pupae located on the soil surface, C. haywardi attacked pupae that were buried up to 5 cm deep, performing better in clayey than in loamy soil. In the second experiment, exposure time (24, 36, 48, and 72 h) had no significant effect on parasitism rates, but soil type did. P. vindemiae again only attacked pupae on the soil surface while C. haywardi was also able to parasitize pupae that were buried up to 5 cm deep. We conclude that C. haywardi represents a viable candidate to replace the environmentally unfriendly P. vindemiae in augmentative biological control programs against fruit flies. 相似文献
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Angus Davison †§ Johnny D. S. Birks † Rachael C. Brookes † John E. Messenger† Huw I. Griffiths‡ 《Molecular ecology》2001,10(10):2479-2488
The flora and fauna of Europe are linked by a common biogeographic history, most recently the Pleistocene glaciations that restricted the range of most species to southern refugial populations. Changes in population size and migration, as well as selection, have all left a signature on the genetic differentiation. Thus, three paradigms of postglacial recolonization have been described, inferred from the patterns of DNA differentiation. Yet some species, especially wide-ranging carnivores, exhibit little population structuring between the proposed refugia, although relatively few have been studied due to the difficulty of obtaining samples. Therefore, we investigated mitochondrial variation in pine martens, Martes martes, in order to understand the extent to which they were affected by glacial cycles, and compared the results with an analysis of sequences from polecats, Mustela putorius. A general lack of ancient lineages, and a mismatch distribution that is consistent with an expanding population, is evidence that the present-day M. martes and Mu. putorius in central and northern Europe colonized from a single European refugium following a recent glaciation. There has also been interspecific mitochondrial introgression between M. martes and the sable M. zibellina in Fennoscandia. 相似文献
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The awareness of the importance of plant biodiversity has been considerably raised in both developed and developing countries over the last decade. Some of the debate has not been helpful in fostering collaboration or progress towards a more rational support network. The paper attempts to identify and categorize existing efforts in operation in a wide range of institutions and bodies ranging from essentially environmentally orientated to crop-based organizations. Current funding and training initiatives are discussed. 相似文献