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排序方式: 共有307条查询结果,搜索用时 8 毫秒
1.
海洋真菌分类鉴定方法探析 总被引:1,自引:0,他引:1
详细介绍了海洋真菌现代分类鉴定方法。先考察其在不同盐度条件下的生长情况,检验分离自海洋的真菌是否为海洋微生物,然后从形态特征、生理生化特征、基因水平3方面指标综合考虑将海洋有丝真菌鉴定到种属水平,确定其系统分类地位。 相似文献
2.
A H Dye 《African Zoology》2013,48(2):201-205
Diurnal vertical migrations of meiofauna were observed in an estuarine sand flat and these were related primarily to desiccation and temperature. The migrations, which occurred in the top 10 cm of the sediment, had a mean range of 5 cm and were most strongly exhibited by the interstitial flatworms, polychaetes and oligochaetes, followed by the nematodes and harpacticoid copepods. It is concluded that vertical migrations are restricted to areas experiencing some degree of desiccation and would not be significant in waterlogged areas such as mud flats. 相似文献
3.
Masoud Shahram Robin A.J. Nicholas Roger J. Miles Ann P. Wood Donovan P. Kelly 《Research in veterinary science》2009,87(3):364-366
Mycoplasma mycoides subsp. mycoides Large Colony (LC) type is a pathogen of goats causing contagious agalactia and respiratory disease, found on all continents where small ruminants are kept. It shares close genetic characteristics with M. mycoides subsp. capri. Substrate oxidation by 22 strains of M. mycoides subsp. mycoides LC from nine countries was compared with that of eight strains of M. mycoides subsp. capri from five countries. There was considerable similarity in the substrates used, but substrate saturation coefficients (Ks) varied for different substrates. Substrate utilization patterns and Ks values did not (1) significantly differentiate the LC strains from each other, (2) show any correlation with geographical origin, or (3) distinguish the LC strains from the capri strains. These results support previous studies justifying the reclassification of these subspecies as a single species. 相似文献
4.
Dantas-Torres F 《Veterinary parasitology》2008,154(1-2):94-97
An abbreviation system for genus names of ticks of the world is proposed. This abbreviation system adopts two letters (typically, the first two), as previously proposed for Culicidae and more recently for Phlebotominae. I hope this abbreviation system will be useful for anyone interested in tick taxonomy and related areas. 相似文献
5.
6.
Newly recorded species of the genus Isohypsibius (Tardigrada; Hypsibiidae) from China 总被引:9,自引:0,他引:9
This paper reports two newly recorded species, lsohypsibius lunulatus Iharos, 1966 and lsohypsibiusprosostomus Thulin, 1928, of the genus lsohypsibius (Tardigrada; Hypsibiidae) from China. The specimens of lsohysibius lunulatus were collected from Taibai Mt (34°18′N, 107°42′E) at 2,500 m a.s.1, and those oflsohypsibius prosostomus from Taibai Mt (34°10′N, 107°35′E) at 2,000 m above sea level. All specimens are deposited at the College of Life Sciences, Shaanxi Normal University, China. A key to the Chinese species of lsohypsibius was also given. 相似文献
7.
思茅松研究现状的探讨 总被引:13,自引:0,他引:13
本文从区系地理、生物特性、生态特点和开发利用等方面对思茅松的研究现状和存在问题作了系统的总结。认为思茅松是个重要的森林树种、在起源及分布上都与云南松和卡西亚松有联系,从理论到生产实践,都需要开展深入细致的研究。 相似文献
8.
S.L. Jackson A. Maxwell T.I. Burgess G.E.StJ. Hardy B. Dell 《Forest Ecology and Management》2008,255(12):3931-3937
Eucalyptus globulus is the predominant exotic hardwood plantation species in Western Australian (WA), and is often planted adjacent to native eucalypt forests. The increase in number of Mycosphaerella species associated with Mycosphaerella leaf disease (MLD) in E. globulus plantations in WA in the past decade has raised concern about the possible movement of pathogens between the native forests and plantations. In order to determine whether the introduction of new E. globulus genetics into WA may have further exacerbated this situation, juvenile and adult foliage were taken from a genetics trial near Albany, WA consisting of 60 full-sib families and Mycosphaerella species identified using morphological and molecular tools. Eleven species of Mycosphaerella were identified from one plantation: Mycosphaerella fori (Pseudocercospora fori) and Mycosphaerella ellipsoidea are new records for Australia; Mycosphaerella tasmaniensis (Passalora tasmaniensis) and Mycosphaerella suttoniae (Kirramyces epicoccoides) are new records for WA; and Mycosphaerella nubilosa, Mycosphaerella cryptica, Mycosphaerella marksii, Mycosphaerella molleriana, Mycosphaerella lateralis, Mycosphaerella aurantia and Mycosphaerella parva, previously recorded for WA. The most frequently isolated species from juvenile foliage was M. marksii (77%) followed by M. nubilosa (33%). M. nubilosa was most frequently isolated from adult leaves (88%) followed by M. parva (7.5%). Three species, M. molleriana, M. lateralis and M. cryptica, were only isolated from adult leaves while M. ellipsoidea was only isolated from juvenile leaves. These records increase the number of known Mycosphaerella species from eucalypts in WA from 10 to 13. The increase in the number, distribution and impact of Mycosphaerella species contributing to MLD in WA is of concern both to the potential productivity of the plantations and the biosecurity of native WA Eucalyptus species. Continued monitoring of the plantation estate is required to understand the dynamics of the host–pathogen interactions. 相似文献
9.
CONFUSACRISVIRIDISSP.NoV.(FIGS-l-5)Ma1eBodysmaller,headshort,lengthshorterthanpronotum.Vertextri-angle,withdistinctmediancarina.Foveolaeabsent,fronsseeninprofileverysloping.Frontalridgedistinct,withashal-lowgrooveinaIlthelength.Eyesoblong,itsverticaldiameterl.4otimesthehorizon-taldiameter,l.l7timesthelengthofsubocularsuture.Antennanarrowensiformandlonger,itslengthl.74timesthelengthofheadandpronotum;thelengthofmiddlejointl.83timesitswidth.Anteriormarginofpronotumstraight,posteriorma… 相似文献
10.
现代技术在昆虫分类中的应用 总被引:3,自引:0,他引:3
介绍形态学、行为学、遗传学、生物化学及分子生物学等几种分类方法在昆虫分类中的应用。 相似文献