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151.
152.
K. B. Ireland D. Hüberli B. Dell I. W. Smith D. M. Rizzo G. E. St. J. Hardy 《Plant pathology》2012,61(2):234-246
Susceptibility to branch dieback caused by Phytophthora ramorum was tested using a detached branch assay for 66 Australian native plant species sourced from established gardens and arboreta in California. Six of these species were further tested for their susceptibility to bole cankers caused by P. ramorum using a sealed log assay. Isopogon formosus and Eucalyptus denticulata were identified as potentially highly susceptible Australian branch dieback hosts. Thirteen potentially tolerant Australian host species included Banksia attenuata, B. marginata, E. haemastoma, E. regnans, Pittosporum undulatum and Billardiera heterophylla. Eucalyptus regnans was identified as a potentially highly susceptible bole canker host, while E. diversicolor and E. viminalis were considered potentially tolerant species to bole cankers caused by P. ramorum. Phytophthora ramorum was able to infect all 66 species, as confirmed by reisolation. These results extend the known potential host range for P. ramorum, confirm it as a possible threat to Australian plant industries and ecosystems and highlight additional associated hosts that are important in the global horticultural trade, native forests and plantation forestry. 相似文献
153.
植物类菌原体系统分类研究进展 总被引:1,自引:0,他引:1
植物类菌原体(Mycoplasmalike Organism,MLO),现称Phytoplasma,是一类严重危害植物的病原原核生物,由于它难以人工培养,对其系统分类存在很大的难度,为此综述了植物类菌原体的系统分类研究最新进展。 相似文献
154.
本文报告了内蒙古中部地区吨粮田条件下,不同植物物料在覆膜和不覆膜、不同时期的分解动态规律,并对不同C/N比小麦秸秆的分解规律做了深入的研究.研究表明,覆膜有利于地温的提高,前期具有增温保墒的作用,促进了土有机质的矿化,有利于植物物料的分解.调节小麦C/N在90~301范围内,随着C/N的降低,物料矿化速率加大,降低土壤有机质含量;而C/N比为101时有利于土壤腐殖质的形成.提出了吨粮田土壤有机质平衡的途径. 相似文献
155.
转基因生物一产生就受到了世人的关注,本文通过详实的资料,阐述了它在多种限制条件下的迅速发展,并向人类展示了光明的开发和利用前景。 相似文献
156.
三重巢式PCR技术检测抗草甘膦转基因大豆深加工产品 总被引:3,自引:0,他引:3
实验以7种具有代表性的含有大豆成分的深加工产品(卵磷脂、大豆蛋白质粉、巧克力饮品、婴儿米粉、大豆粗油、大豆精炼油和大豆色拉油)作为样品进行定性检测,第一轮三重PCR均未能扩增出任何大豆成分,其灵敏度为0.5%。第二轮三重PCR可以扩增出除大豆精炼油和色拉油以外的所有深加工产品的内源基因Lectin、35S-CTP和EPSPS-NOS基因,其检测灵敏度达到0.005%,结果提示三重巢式PCR检测方法适用于大豆深加工产品的定性检测。 相似文献
157.
The Weighted Coenotic Index (WCI) is a single value that unifies total abundance, dominance structure, species richness and ecological weightings, e.g., habitat preferences and positions of species in the r/K continuum. Studies with simulated species assemblages have shown that ecological weightings and dominance structure are major components of the index; the ecological weightings must be related to the group of organisms studied and to the scope of the investigation. The WCI is a relative measure that needs a reference (control) site in each investigation for a conclusive interpretation. Compared to several diversity indexes, the WCI has a much better discriminant ability because it includes ecological weightings and a log-normal dominance structure. This index has been applied to published data from several field studies using protozoa (testate amoebae, ciliates) and earthworms. The results show that the WCI is an appropriate tool to measure changes and to monitor recovery processes in disturbed ecosystems. The index should be calculated separately for each systematic (indicator) group (e.g., ciliates, nematodes, mites) because the information will be more detailed and an overall index could, for instance, mask a high value for one group, such as ciliates, in conjunction with a low value for another group, such as nematodes. The WCI has been developed on a protozoological background owing to the authors' familiarity with this field. Mathematically and practically it is also applicable to other groups of soil and freshwater organisms. 相似文献
158.
氧化应激(oxidative stress)是指由于外界环境的刺激使机体内活性氧(ROS)增加,导致氧化/抗氧化动态平衡遭到破坏的一种应激反应。在正常情况下,动物机体内参与活性氧产生和清除的系统处于动态平衡。由于外界环境刺激或机体自身变化等原因,使ROS产生增多或其清除能力下降时,机体就会出现氧化应激(氧化胁迫)。长期或过强的氧化应激会引起水生生物生长发育缓慢、免疫机能下降、疾病发生等危害,导致水产品质量下降、营养价值降低,给水产养殖业造成严重经济损失。Nrf2-Keap1/Are信号通路在抵抗外源性或内源性氧化应激的过程中起着至关重要的作用,该信号通路在哺乳动物中得到了广泛研究,但在水生生物中的研究尚未见系统综述。作者在综合了大量文献的基础上,针对鱼类及虾蟹类等水生生物,介绍了氧化应激产生的机理、Nrf2和Keap1的分子基础、Nrf2-Keap1/Are信号通路作用方式,以及该信号通路在水生生物方面的相关研究进展等,为水生生物抗氧化应激机制的深入研究提供理论参数和相关数据支持。 相似文献
159.
Masayuki YAMAMOTO Hiroyasu MAKINO Jun-ichiro KOBAYASHI Osamu TOMINAGA 《Fisheries Science》2004,70(6):1098-1105
ABSTRACT: The abundance of food organisms and feeding habits of larval and juvenile Japanese flounder were examined during the period from May to August in 1999, 2000 and 2001 at the sandy Ohama beach, the central Seto Inland Sea. The food organisms collected with a sledge net consisted of 40 families from 18 orders, dominated by mysids, crangonids and gammarids. The mean densities of mysids, crangonid shrimp ( Crangon spp.), gammarids and fish were 2.74, 6.74, 2.91 and 0.15 individuals/m2 , respectively. The main prey of the flounder ( n = 202; range of total length 9.80–75.95 mm) was mysids and small crangonid shrimp (<14 mm in body length). Prey fish availability was low, as the density of fish was low. The small crangonid shrimp was abundant, and the large crangonid shrimp, which could prey on larval flounder, was not abundant. The crangonid shrimp was important not as a predator for the flounder but as prey. The flounder preferred epifaunal mysids, Nipponomysis ornata and Anisomysis ijimai , to sand-burrowing mysids, Iiella oshimai , and avoided crangonid shrimp. 相似文献
160.
桃溃疡病病原菌的研究 总被引:1,自引:0,他引:1
本文报导了桃树上的一个新病害。经鉴定,病原菌为Cylindrocladium scoparium Morgan.对該病所引起的症状、病原菌形态、致病性及其寄主范围作了研究。 相似文献