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11.
实验室条件下系统研究了磷化氢(PH3)对储物害虫嗜卷书虱Liposcelis bostrychophila卵、各龄若虫和成虫的致死作用,并选用PH3间歇熏蒸以及PH3与气调交替处理等措施对嗜卷书虱进行处理,比较了不同处理措施对嗜卷书虱种群的控制效果。结果表明,PH3熏蒸处理对嗜卷书虱各虫态有不同的致死效果。对卵而言,24、72和120 h熏蒸处理的LC50分别为0.137、0.045和0.035 mg/L;而24 h熏蒸处理对若虫的LC50在4.285~7.364 μg/L之间,对成虫的LC50为20.404 μg/L;采用25 μg/L的PH3进行24 h熏蒸处理,间隔10 d后再分别进行第2次和第3次熏蒸处理,可以完全控制嗜卷书虱的发生。采用PH3 (12 μg/L)和气调(体积比例为35% CO2,1% O2,64% N2)交替处理能够延缓嗜卷书虱种群抗性的发展,交替处理3~5次可以完全控制嗜卷书虱的发生。 相似文献
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G. DAHAL 《Integrated Pest Management Reviews》1997,2(3):139-159
Research on insect pests (including leafhoppers and planthoppers) in Nepal was initiated in 1956 by the Entomology Division and Plant Protection Units of the Department of Agriculture. More systematic work began after the establishment of a Rice Improvement Programme in 1972. Because of poor documentation and publication of research findings, it is difficult to assess the research efforts and achievements to date. The available research reports are mostly published in the proceedings of national seminars/workshops. They are used here to assess the current status of research on the occurrence and damage caused, distribution and composition, relative abundance, biology and management through chemicals. Much of past research has focused on insect surveys by light traps and sweep nets and the evaluation of insecticides and, since early 1990, some research on rice green leafhoppers (Nephotettix virescens and Nephotettix nigropictus) has begun to determine their relative abundance and population characteristics in relation to their potential as vectors of rice viruses. The challenges to pest management in general and some suggestions for future research needs are discussed, based on the present standing of agricultural research in the country 相似文献
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甘蓝多酚氧化酶的生物化学性质及其杀虫剂的诱导作用 总被引:2,自引:0,他引:2
采用时间动力学法,在研究了甘蓝多酚氧化酶的最适反应条件的基础上,对有机溶剂和杀虫剂对多酚氧化酶活性的影响进行了研究。结果表明:甘蓝多酚氧化酶反应的最适pH值为6.4,最适反应温度为55℃;丙酮和乙醇对多酚氧化酶活性有明显的激活作用;高效氯氰菊酯、灭多威和辛硫磷以及小菜蛾和桃蚜取食的胁迫会对多酚氧化酶的活性产生影响。 相似文献
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Although adult Rumex obtusifolius are problematic weeds, their seedlings are poor competitors against Lolium perenne, particularly in established swards. We investigated the possibility of using this weakness to augment control of R. obtusifolius seedlings with combinations of Gastrophysa viridula (Coleoptera: Chrysomelidae) and the rust fungus Uromyces rumicis. Rumex obtusifolius seedlings were grown in competition with L. perenne sown at different rates and times after R. obtusifolius: they competed successfully with L. perenne when sown 21 days before the grass. Sowing both species at the same time resulted in a dominant grass sward, with R. obtusifolius becoming dominant when sown 42 days prior to L. perenne. Grass sowing rate had no effect on R. obtusifolius growth or biomass. A second experiment investigated how competition from L. perenne sown 21 days after R. obtusifolius combined with damage from G. viridula and/or U. rumicis (applied at either the 3–4‐ or 10–13‐leaf stage, or at both stages) affected the growth and final biomass of R. obtusifolius. Beetle grazing at the latter leaf stage was the only treatment that reduced R. obtusifolius biomass, although rust infection at the earlier application led to an increase in shoot and root weight. The results are discussed in terms of the potential for use of these agents in the field. 相似文献
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《The Journal of Applied Poultry Research》2015,24(2):215-221
During the past two decades, food safety issues in China not only posed serious threats to Chinese consumers but also damaged the image of Chinese products internationally. In China, food safety is not only about scientific discoveries, advanced laboratories, and sanitation equipment; it is more about the role of different players in the food supply chain. The poultry meat supply chain is instrumental in the spread of the avian influenza A virus (H7N9), raising questions about how policymakers respond to such threats and whether industries need to be restructured to manage and control this epidemic so that it does not recur. As a short-term measure, to prevent the spread of this disease, government authorities enforced the closure of live bird markets (LBM) in disease-affected areas of China. However, in the long term, the poultry meat supply chain needs to be restructured. The aim of the current study was to analyze distribution channels for chicken meat in China and then describe arrangements in poultry meat sectors that incorporate small- and medium-scale producers into the supply chain while responding to shifts in LBMs. We also assessed the role of LBMs in spreading H7N9 and how these interventions affect the poultry meat supply chain in the Chinese market. 相似文献
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通过分析森林生物多样性与森林病虫害的现状及其对森林可持续发展的意义,提出了提高意识、加强管理,依靠科技手段保护生物多样性和防治病虫害等措施建议,以期可持续发展森林保护与利用。 相似文献
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The aim of this study was to develop a novel oil-in-water (O/W) emulsion as adjuvant diluents (AD) for live vaccine against classical swine fever (CSF) that could effectively enhance the immune effect of vaccine.The AD was prepared by high-pressure homogenization technique.Formulations and preparation parameters were optimized with response surface design.Its stability, particle size, polydispersity (PDI) and Zeta potential were characterized.The humoral immune response and cellular immune response of the AD were evaluated with BALB/c mice by intramuscular injection.The particle size of the AD prepared by optimized formulation and parameters was 100.4 nm, PDI was 0.147, and Zeta potential was —28.7 mV.The experiment results showed that the AD had good stability.The AD was inoculated combined with live vaccine against CSF into BALB/c mice by intramuscular injection.The results showed that the live vaccine against CSF specific immune responses could be evoked in mice by co-inoculation with AD and vaccine.The cellular immune response levels in co-inoculated groups were significantly higher than control group (P<0.05), with obvious phenomena of higher levels of IFN-γ, IL-6 and IL-4 in serum.The result revealed that cellular immune capability significantly improved with the AD.The results strongly revealed that cellular immune capability significantly improved by introducing AD for effective immune-adjuvant for live vaccine against CSF. 相似文献