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Huaping Zhao Zhipeng Cui Yucheng Gu Yuxiu Liu Qingmin Wang 《Pest management science》2011,67(9):1059-1061
Natural tetramic acid derivatives have attracted a great deal of interest of chemists because of their structural features and the broad range of biological activities. This paper focuses on five naturally occurring tetramic acid derivatives reported to have phytotoxicity and discusses their common structural characteristics. Copyright © 2011 Society of Chemical Industry 相似文献
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2006年来,宁波出入境检验检疫局植检实验室曾多次从进境木质包装中首次截获并报道非洲伞滑刃组(africanus group)线虫,它们分别为非洲伞滑刃线虫(Bursaphelenchus africanus Braasch, Gu, Burgermeister, Brandstetter &; Metge, 2006)、伯氏伞滑刃线虫(B. burgermeisteri Braasch, Gu, &; Brandstetter, 2007)和欧斐切伞滑刃线虫(B. obeche Gu, Braasch, Zhen, Burgermeister &; Lin, 2008)。这些线虫均为作者最先截获。非洲伞滑刃组线虫的主要鉴定特征是:侧线4条;尾乳突7个(第3对和第4对靠近并位于交合伞起始处,第3对略位于第4对前并更靠近腹面);交合刺较直,中部有横纹,冠状体愈合(基顶和喙突不明显),远端无盘状突;后阴子宫囊约占肛阴距1 /2。目前尚无关于该组线虫媒介昆虫及致病性的报道。 相似文献
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AG-A belongs to the binucleate Rhizoctonia (BNR) anastomosis group (AG) of the Ceratobasidium teleomorph, which parasitizes the roots of many plant species. Ninety nine isolate species of AG-A were obtained from Tibet,
Sichuan, and Yunnan Province in China. All isolates were divided into three types based on their cultural characteristics.
Type I: abundant aerial mycelia, dense hyphae, loose sclerotia; Type II: abundant aerial mycelia, no sclerotia. Type III:
sparse aerial mycelium and no sclerotia. All of the isolates infected the seedlings of Chinese mustard and Chinese cabbage,
causing the formation of lesions on the stem and a brown discoloration of the roots. Sequence analysis of the 5.8S rDNA-ITS
showed a similarity of 98–100% among the isolates. Inter Simple Sequence Repeat (ISSR) was used to detect genetic variation
in binucleate Rhizoctonia spp. Forty two AG-A isolates were amplified using 15 random primers. From a total of 164 bands, 144 bands (87.8%) were polymorphic
in the 42 tested isolates. A dendrogram showing genetic relationships between the isolates was constructed using unweighted
pair-group averages based on genetic distances. According to the dendrogram, the 42 tested isolates could be aligned into
three clusters with a genetic similarity coefficient of 0.29, the first clusters including 27 isolates with III of culture
characteristics on PDA; the second clusters included eight isolates with I of cultural characteristics on PDA; the third cluster
included seven isolates with II of cultural characteristics on PDA. The results of ISSR analysis showed an association between
the hosts of these isolates. Our results showed that ISSR analysis can reveal more molecular variation among isolates of AG-A
than sequence analysis using the 5.8S rDNA-ITS. 相似文献
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