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Benomyl affected populations of Tetranychus urticae by interfering with the pathogenic fungus, Neozygites floridana. Benomyl delayed but prolonged spider mite outbreaks. Few mites were infected with the pathogen when benomyl was used. Reductions in mite populations treated with fentin hydroxide were associated with a high incidence of N. floridana infection. Benomyl did not affect sporulation of N. floridana but appeared to inhibit conidial germination or growth of the fungus.
Résumé Le bénomyl a modifié les populations de Tetranychus urticae Koch en interférant avec son champignon pathogène, Neozygites floridana (Weiser & Muma). Le bénomyl retardait mais prolongeait les pullulations de l'acarien. Peu d'acariens étaient infectés par le champignon quand on utilisait du bénomyl. Les réductions des populations d'acariens traitées avec l'hydroxyde de fentine étaient associées à un haut niveau d'infection par N. floridana. Le bénomyl ne modifiait pas la sporulation de N. floridana mais semblait inhiber la germination des conidies ou la croissance du champignon.
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Based on their developmental patterns, the bony tentorium (BT) and bony falx (BF) of mammals can be classified into two types, the carnivoran type and the dolphin type. The former develops as part of the skull bones during the fetal period and is already completed at birth, while the latter is gradually formed by ossification in the tentorium cerebelli (TC) and falx cerebri (FC) during the course of aging. The BT of spider monkeys is assigned to the dolphin type.  相似文献   
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蜘蛛的物种多样性是极其丰富的,但目前只有一小部分的蜘蛛种类被描述。世界上已描述的蜘蛛种类已超过40000种,隶属于110个科。在我们居住的小范围内,可能至少有30个科的数百种蜘蛛。就中国而言,估计可能有40000种以上的蜘蛛种类,但目前也只有大约4000种被命名。本检索表首次列出了中国现有67个蜘蛛科的答定特征.以及不同科之间的相似处和不同处。  相似文献   
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中国蜘蛛物种多样性分析   总被引:1,自引:0,他引:1  
基于2011年1月更新的世界蜘蛛名录第11.5版,本文对中国蜘蛛的物种多样性进行了统计和分析:(1)目前中国共记述蜘蛛67科670属3667种,种数占世界蜘蛛的8.72%,仍有许多物种尚待发现;(2)目前中国特有蜘蛛物种共计2376种,占中国蜘蛛种数的64.79%、世界蜘蛛种数(42055种)的5.65%,表明中国蜘蛛特有物种极为丰富,为中国生物多样性的保护、环境及气候的历史演变和蜘蛛的系统演化研究起到重要作用;(3)已知蜘蛛物种数最多的省份为云南(728种,占19.85%)、湖南(612种,占16.69%)、四川(454种,占12.38%)等,一定程度上表明上述各省生物多样性丰富,但这一结果也与各地蜘蛛多样性研究不均衡有关。蜘蛛各科名录及统计数据可参见“中国蜘蛛特有物种网”。  相似文献   
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The use of continuous quantitative characters for phylogenetic analyses has long been contentious in the systematics literature. Recent studies argue for and against their use, but there have been relatively few attempts to evaluate whether these characters provide an accurate estimate of phylogeny, despite the fact that a number of methods have been developed to analyze these types of data for phylogenetic inference. A tree topology will be produced for a given methodology and set of characters, but little can be concluded with regards to the accuracy of phylogenetic signal without an independent evaluation of those characters. We assess the performance of continuous quantitative characters for the mygalomorph spider genus Antrodiaetus, a group that is morphologically homogeneous and one for which few discrete (morphological) characters have been observed. Phylogenetic signal contained in continuous quantitative characters is compared to an independently derived phylogeny inferred on the basis of multiple nuclear and mitochondrial gene loci. Tree topology randomizations, regression techniques, and topological tests all demonstrate that continuous quantitative characters in Antrodiaetus conflict with the phylogenetic signal contained in the gene trees. Our results show that the use of continuous quantitative characters for phylogenetic reconstruction may be inappropriate for reconstructing Antrodiaetus phylogeny and indicate that due caution should be exercised before employing this character type in the absence of other independently derived sources of characters.  相似文献   
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Crabs of the family Hymenosomatidae are common in coastal and shelf regions throughout much of the southern hemisphere. One of the genera in the family, Hymenosoma, is represented in Africa and the South Pacific (Australia and New Zealand). This distribution can be explained either by vicariance (presence of the genus on the Gondwanan supercontinent and divergence following its break-up) or more recent transoceanic dispersal from one region to the other. We tested these hypotheses by reconstructing phylogenetic relationships among the seven presently-accepted species in the genus, as well as examining their placement among other hymenosomatid crabs, using sequence data from two nuclear markers (Adenine Nucleotide Transporter [ANT] exon 2 and 18S rDNA) and three mitochondrial markers (COI, 12S and 16S rDNA). The five southern African representatives of the genus were recovered as a monophyletic lineage, and another southern African species, Neorhynchoplax bovis, was identified as their sister taxon. The two species of Hymenosoma from the South Pacific neither clustered with their African congeners, nor with each other, and should therefore both be placed into different genera. Molecular dating supports a post-Gondwanan origin of the Hymenosomatidae. While long-distance dispersal cannot be ruled out to explain the presence of the family Hymenosomatidae on the former Gondwanan land-masses and beyond, the evolutionary history of the African species of Hymenosoma indicates that a third means of speciation may be important in this group: gradual along-coast dispersal from tropical towards temperate regions, with range expansions into formerly inhospitable habitat during warm climatic phases, followed by adaptation and speciation during subsequent cooler phases.  相似文献   
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Five anthocyanins, cyanidin 3-(2′′-(6′′′-caffeoyl-β-glucopyranosyl)-6′′-(E-p-coumaroyl)-β-glucopyranoside)-5-β-glucopyranoside, cyanidin 3-(2′′-(6′′′-E-sinapoyl-β-glucopyranosyl)-6′′-(E-p-coumaroyl)-β-glucopyranoside)-5-β-glucopyranoside, cyanidin 3-(2′′-(6′′′-feroyl-β-glucopyranosyl)-6′′-(E-p-coumaroyl)-β-glucopyranoside)-5-β-glucopyranoside, pelargonidin 3-(2′′-(6′′′-E-sinapoyl-β-glucopyranosyl)-6′′-(E-p-coumaroyl)-β-glucopyranoside)-5-β-glucopyranoside, and pelargonidin 3-(2′′-(6′′′-E-p-coumaroyl-β-glucopyranosyl)-6′′-(E-p-coumaroyl)-β-glucopyranoside)-5-β-glucopyranoside, together with five known anthocyanins have been identified in flowers of Cleome hassleriana Queen line. One monoacylated and four diacylated cyanidin 3-sophoroside-5-glucosides were identified as the main anthocyanins in flowers with mauve colouration, while a homologous glycosidic pattern based on pelargonidin was found in the five main anthocyanins from flowers with pink colouration. The anthocyanins identified in C. hassleriana share the same glycosidic pattern as anthocyanins isolated from the genera Raphanus, Brassica and Iberis in the sister family Brassicaceae.  相似文献   
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