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31.
兰科Orchidaceae植物金线莲Anoectochilus roxburghii(Wall.)Lindl是一种在中国广泛使用的中草药.本文首次报道两种迟眼蕈蚊属害虫危害金线莲,即Bradysia impatiens(Johannsen,1912)和Bradysia ocellaris(Comstock,1882).... 相似文献
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SALMAN A. AL‐SHAMI JANI HEINO M. R. CHE SALMAH A. ABU HASSAN A. H. SUHAILA MADZIATUL R. MADRUS 《Freshwater Biology》2013,58(6):1126-1137
1. There has recently been increasing interest in patterns of beta diversity but we still lack a comprehensive understanding of these patterns in various regions (e.g. the tropics), ecosystems (e.g. streams) and organism groups (e.g. invertebrates). 2. Our aim was to investigate the patterns of beta diversity of stream macroinvertebrates in relation to key environmental (i.e. stream size, pH and habitat degradation) and geographical variables (i.e. latitude, longitude, altitude) in a tropical region. We surveyed a total of 8–10 riffle sites in each of 34 streams (altogether 337 riffle sites were sampled) in Peninsular Malaysia to examine variation in macroinvertebrate community composition at within‐stream and among‐stream scales. 3. Based on test of homogeneity of dispersion, we found that the streams studied differed significantly in within‐stream variation in community composition (i.e. among‐site variation of within stream beta diversity). The patterns were similar based on Bray–Curtis coefficient on abundance data, Sorensen coefficient on presence–absence data and Simpson coefficient on presence–absence data. We also found that within‐stream beta diversity was significantly related to stream size, pH and latitude, with each of these variables individually accounting for around 20% of the variation in beta diversity in simple regressions, while the total variation explained by the three significant variables amounted to around 50% in multiple regressions. By contrast, habitat degradation, longitude and altitude were not significantly related to beta diversity. We also found that the factor drainage basin accounted for much of the variation in beta diversity in general linear models, suppressing the effects of environmental variables. 4. We concluded that within‐stream beta diversity is mainly related to a combination of the identity of a drainage basin and stream environmental factors. Our findings provide important background for stream environmental assessment and conservation planning by emphasising that (i) macroinvertebrate communities within streams are not homogeneous, but show considerable beta diversity, (ii) streams differ in their degree of within‐stream beta diversity, (iii) stream size and water pH should be considered in applied contexts related to within‐stream beta diversity and (iv) historical effects may be different in different drainage basins and may affect present‐day patterns of within‐stream beta diversity. 相似文献
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报道巴基斯坦角顶叶蝉亚科1新纪录属Changwhania Kwon和1新纪录亚属Limotettix(Scleroracus)Van Duzee,并记述2新纪录种Changwhania ceylonensis Baker,1925 n.rec.和Limotettix(Scleroracus)cacheolus n.rec.。 相似文献
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CHANG Guobin CHANG Hong LIU Xiangping YANG Zhangping CHEN Guohong ZHAO Wenming JI Dejun XUE Yan HUANG Feng HASSAN Hussein 《中国科学C辑(英文版)》2006,49(2):172-181
Genetic coadaptability of wild Japanese quail, wild Common quail and Domestic quail populations in China was studied using
7 microsatellite DNA markers and Monte Carlo method to test genetic disequilibrium. The molecular effects of genetic coadaptability
were analyzed through a new statistical model of neutral site. The results showed that genetic coadaptability dominated the
genetic disequilibrium of the three quail populations, and totally 16.67%, 9.66% and 10.05% of non-allelic combinations were
in the genetic disequilibrium in wild Japanese quail, wild Common quail and Domestic quail populations, respectively. Genetic
coadaptability existed at almost all the tested sites. In the molecular point of view, genetic coadaptability plays an important
role of keeping lots of polymorphisms in natural populations. Therefore, it is another key factor to the genetic disequilibrium
in the population except for linkage. The results enrich the conceptions and connotations of genetic disequilibrium, and help
us know more about genetic coadaptability and its effects, and lay a foundation of evaluation and protection of wild quail
genetic resources in China. 相似文献
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JUSTIN N. OKOLLE MASHHOR MANSOR ABU HASSAN AHMAD 《Insect Science》2006,13(5):381-389
Spatial distribution of immatures of the banana skipper (Erionota thrax L.) and their parasitisms from three major parasitoids were studied in a Cavendish banana plantation from April 2004 to December 2004. Infestation levels and parasitism of E. thrax life stages were recorded from bunched plants (BP), flowering plants (FP), preflowered plants (PF), broad leaf followers (BLF) and narrow leaf followers (NLF), as well as on well managed and poorly managed plants. Mean numbers of the immatures and numbers parasitized from the nine blocks in the plantation were fitted to four dispersion indices. Significant numbers of E. thrax immatures and those parasitized by Ooencyrtus erionotae, Cotesia erionotae and Brachymeria albotibialis were recorded from BLF and PF; no eggs were found on BP and FP. Although infestation was higher on well managed plants, only larval parasitism was significantly different. Three of the four indices indicated that eggs and larvae were random while all the indices showed pupae to be clumped. Parasitized eggs and pupae were clumped (4/4 indices) while 3/4 indices revealed a random pattern for parasitized larvae. 相似文献
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HASSAN A. MOHAMED GEORGE A. INGRAM DAVID H. MOLYNEUX 《Medical and veterinary entomology》1992,6(3):217-224
Lectins that agglutinate red blood cells (RBC) were demonstrated in Anopheles gambiae mosquito haemolymph and gut extracts. No apparent differences in haemagglutinin titres were detected between male and female mosquitoes and overall agglutinin levels were not increased following a bloodmeal. Titres were highest in the haemolymph and midgut extracts versus human AB, horse, chicken and goat RBCs and in hindgut against human AB, chicken and sheep; foregut extract gave relatively low titres. Adsorption of haemolymph and gut extracts with selected RBCs coupled with carbohydrate inhibition and the use of enzyme-treated RBCs revealed the presence of multiple (hetero-) agglutinins. An.gambiae lectins were specific for (1-1)-, (1-4)- or (1-6)-linked glucose based disaccharides, glucose and its (1-2) or (1-3) linkages with fructose and, to a lesser extent, aminated or N-acetylated glucose, or galactose and its deoxy derivatives. This study presents the first report of the occurrence of heterogenous anti-RBC agglutinins in haemolymph and gut extracts of the mosquito An.gambiae, together with the sugar-binding specificities of these lectins. 相似文献
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The spatial distribution and density of scientists can have important implications for key aspects of scientific processes, such as innovation, networking, rates of knowledge exchange and success in large competitive grants. In this paper, we examine the research output of different research organizations and universities in Australia, with the aim of identifying hotspots of ecological research and how these hotspots have changed over the last 20 years. We used publications from 10 reputable peer‐reviewed international journals as a measure of research output. We identified a number of ecology hotspot clusters. Some clusters have developed significantly over the last 20 years, while others have declined in output over time. The University of Sydney, University of Queensland, James Cook University and Melbourne University had the largest output levels among universities. Results also showed large increases in output over the last 5‐year period (2006–2010), possibly because of the impending introduction of the Excellence in Research for Australia. 相似文献
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