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The karyotypes of six species of Solms-laubachia and one each of Parrya and Desideria (Brassicaceae) from the Himalayan-Hengduan Mountains (Tibet, Sichuan and Yunnan provinces) were investigated. Chromosome counts of S. xerophyta , S. lanata, S. platycarpa and D. baiogoinensis are reported for the first time and found to be diploid with 2 n  = 14. Diploid counts were also made of S. retropilosa , a species previously known to be a tetraploid. The karyotype formulae of D. baiogoinensis , S. eurycarpa , S. pulcherrima , S. retropilosa , S. xerophyta and S. platycarpa are 2 n  = 14 = 6 m + 6sm + 2st, whereas those of S. lanata and P. nudicaulis are 2 n  = 14 = 6 m + 2sm + 6st and 2 n  = 14 = 8 m + 4sm + 2st, respectively. Karyotypes and counts of S. eurycarpa and S. pulcherrima are in agreement with prior studies. The relationships within Solms-laubachia and among the three genera are discussed. Speciation within Solms-laubachia may have been the result of primarily intrachromosomal variation at the diploid level, and the genus probably evolved within the Himalayan-Hengduan Mountains instead of migrating from other regions.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 77−86.  相似文献   
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从土壤中分离纯化真菌并鉴定为烟曲霉L-3。以菌株L-3作为固定化载体,将地衣芽孢杆菌固定在真菌上组成固定化体系。研究了混菌菌丝球,菌丝饼,发酵混合液,粗漆酶液对刚果红染料废水的降解情况并对染料废水进行毒性试验。结果表明,菌丝球对染料废水的降解效果最显著,降解率高达99.96%,菌丝饼仅用20 s降解率为91%,发酵混合液与粗漆酶液的处理效果并不显著。该体系对染料废水的去毒率较明显,尤其是菌丝球的去毒率可达到78%。可见,固定化体系对染料废水不但有较高的降解能力,也有较高的去毒率。  相似文献   
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Poisoned protein baits comprise a recognized method for controlling tephritid fruit flies in the form of a ‘lure‐and‐kill’ technique. However, little is known about how a fly's internal protein and carbohydrate levels (i.e. nutritional status) might influence the efficacy of this control. In the present study, the relationships between the internal levels of protein (as measured by total body nitrogen) and carbohydrate (as measured by total body carbon) of the fruit fly Bactrocera tryoni (Froggatt) (Diptera: Tephritidae) are investigated, as well as its foraging behaviours in response to protein, fruit and cue‐lure (a male‐specific attractant) baits. Small cage behavioural experiments are conducted using flies from cultures of different nutritional status and wild flies sampled from the field during the fruiting cycle of a guava crop. For female flies, increasing total body nitrogen is correlated with decreased protein foraging and increased oviposition activity; increasing total body carbon levels generate the same behavioural changes except that the oviposition response is not significant. For males, there are no significant correlations between changes in total body nitrogen and total body carbon and protein or cue‐lure foraging. For wild flies from the guava orchard, almost all of them are sexually mature when entering the crop and, over the entire season, total body nitrogen and total body carbon levels are such that protein hunger is unlikely for most flies. The results infer strongly that the requirements of wild, sexually mature flies for protein are minimal and that flies can readily gain sufficient nutrients from wild sources for their physiological needs. The results offer a mechanistic explanation for the poor response of male and mature female fruit flies to protein bait spray.  相似文献   
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S. M. HAQ 《Journal of Zoology》1965,144(2):175-201
The development of Euterpina acutifrons is described from observations of individuals reared in the laboratory. The characteristics which enable the various stages to be identified have been listed and the feeding mechanism of the larvae described. Differences from the usual developmental pattern of the Harpacticoida are noted and it is suggested that these are related to the pelagic habit of Euterpina . Dimorphism in the male is described and the course of development of the dimorphs is shown to differ from schemes previously suggested for other copepods. Dimorphism, which is manifested at the moult of the third copepodid, is shown to be independent of temperature.  相似文献   
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