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11.
铆钉菇菌丝体液体培养条件及产胞外多糖的研究   总被引:3,自引:0,他引:3  
[目的]为食用菌液体培养和胞外多糖的研究提供基础。[方法]研究铆钉菇菌丝体的最佳液体培养条件,并对其产胞外多糖的情况进行测定。[结果]铆钉菇菌丝体深层发酵适宜的培养基组成为:蔗糖20 g/L、酵母浸膏2 g/L、K2HPO40.5 g/L、MgSO40.5g/L、Vc 0.001 g/L,适宜培养温度28℃,pH值7.0。铆钉菇菌丝体液体培养7 d,菌丝体干重为28.0 g/L,胞外多糖产量为3.27 g/L。[结论]铆钉菇菌丝体液体培养可很好地生长,并产生较多的胞外多糖。  相似文献   
12.
Abstract –  The effectiveness of a pool-and-weir fish pass in the regulated river Laarse Beek (Belgium) was assessed for bullhead ( Cottus gobio ), perch ( Perca fluviatilis ) and roach ( Rutilus rutilus ) from August 2002 to April 2003. Fish were caught by electrofishing downstream, within and upstream of the fish pass. They were marked with visible implant elastomer tags and released downstream of the fish pass. Our results suggest that the fish pass is ineffective for the bullhead because none of the 1270 tagged bullheads were recaptured in the upstream study area. Passage failure most likely resulted from excessive water velocities in the fish pass. On the contrary, 8% of the tagged perch and 29% of the tagged roach were recaptured in the upstream study area. Several management strategies are proposed to allow free upstream passage of the endangered bullhead at the fish pass under study.  相似文献   
13.
The Caspian roach (Rutilus rutilus caspicus) is regarded as one of the most important commercial species in the Caspian Sea. Despite the commercial and conservation importance of the species, information on genetic relationships and diversities at the molecular level in Rutilus rutilus caspicus is scarce. Six microsatellite loci were analysed to study the genetic variation in two major populations of Caspian roach in the Iranian waters of the Caspian Sea: the Anzali Wetland and Gorgan Bay. The Fst value between populations was 0.07, suggesting that the genetic differentiation was significant (P<0.01). Both the studied populations deviated from Hardy–Weinberg equilibrium proportions at a number of loci, mostly due to the deficiency of heterozygosities. The genetic distance between populations was 0.29, which indicates that the genetic difference among the studied populations is pronounced. The differences between both populations were not statistically significant (P>0.05), neither for average number of alleles per locus nor for observed heterozygosities. The data generated in this study provide useful information on the genetic variation and differentiation in populations of Caspian roach.  相似文献   
14.
通过单因素试验和正交试验优化了超声-乙醇法提取血红铆钉菇(Chroogomphus rutilus)子实体中总黄酮的工艺。结果表明,血红铆钉菇中总黄酮最佳提取条件为70%乙醇,料液比1∶30(m/V),超声时间30 min,最佳工艺条件下总黄酮提取率为5.91%。  相似文献   
15.
16.
Abstract – We compared fish microhabitat use patterns in the littoral zone of a lake using a new direct method (point abundance sampling by scuba, PASS) and the widely used point abundance sampling by electrofishing technique (PASE). We collected microhabitat data for age 0+ roach ( Rutilus rutilus L.), perch ( Perca fluviatilis L.), and pike ( Esox lucius L.). The two methods yielded different results for fish assemblage structure and microhabitat patterns. Using PASE, fish were mainly found in "shelter habitats" such as shallow waters and dense vegetation. It is likely that this behavior is caused by the disturbance of the observer stamping around. Using PASS, fish escapement behavior was rarely observed. Therefore, we concluded that this direct and nondestructive sampling technique can be used to provide an accurate microhabitat estimation of a fish community and is assumed to be more suitable than PASE for fish habitat studies.  相似文献   
17.
[目的]优化血红铆钉菇菌丝体液体的发酵条件。[方法]采用液体发酵培养血红铆钉菇菌丝体,先用单因素试验分别考察培养时间和培养基起始pH值等因素对菌丝体产量的影响,然后通过正交试验确定适于血红铆钉菇菌丝体液体发酵生产菌丝体的培养条件。[结果]血红铆钉菇菌丝体的最佳培养时间至少为6 d,液体种子接种量应在10%以上,培养基的pH值以8.5为最好,装液量为200ml/500 ml三角瓶对菌丝体的生长较为有利,最适转速控制在180 r/min。通过正交试验优化的血红铆钉菇菌丝体液体发酵条件为:培养基初始pH值为9.0,装液量为200 ml/500 ml三角瓶,液体种子接种量为12.5%,培养时间为7 d,培养温度为28℃。在此条件下,菌丝体产量可达(9.320±0.151)g/L。[结论]该研究为获得最高产量的血红铆钉菇菌丝体提供了科学依据。  相似文献   
18.
文中介绍了血红铆钉菇的分布、形态特征、生态特性、化学成分及药理功能,并结合国内开发利用现状与出现的问题对长白山野生血红铆钉菇的发展前景进行展望。  相似文献   
19.
Understanding the forces that drive habitat selection of species in communities is important in both ecology and evolution. In nature, species face variation in competition, predation and physical characters among habitats. Vendace (Coregonus albula (L.)) is a specialised zooplanktivorous fish predominantly using deeper water in lakes during summer, while roach (Rutilus rutilus (L.)) uses mainly the shallow littoral zone as well as the upper layer of the pelagic zone. To understand mechanisms behind habitat use of these species, I first conducted a predation experiment to investigate their sensitivity to predation by perch (Perca fluviatilis L.). Second, I performed a foraging experiment using different temperature and light treatments. I then used metabolic calculations to estimate energetic costs when foraging. I found no difference between species regarding sensitivity to predation. Vendace was the most efficient forager on zooplankton but also swam faster spending more energy compared to roach. Roach had a comparatively high metabolic rate in the lowest temperature, where their foraging efficiency was lowest. The energy gain ratio at 6°C was highest for vendace, while it was lowest for roach. In the highest temperature (18°C) and the lowest light level (1 lux), both species were similar in their energy gain ratio. The relative energy gain ratio provides a mechanism to explain habitat distribution for the two species. An increased understanding of the role of metabolism in combination with biotic interactions and habitat use may help to foresee effects of environmental change for different species.  相似文献   
20.
血红铆钉菇对土传病原菌抑菌性研究   总被引:5,自引:0,他引:5  
在24种培养基上对血红铆钉菇子实体进行分离培养,对分离的菌种与病原菌立枯丝核菌、茄孢镰刀菌、链格孢、终极府霉、根癌菌在PDA平板上进行对峙测试,结果对病原菌立枯丝核菌能够重寄生,对茄孢镰刀菌产生抑菌带,对链格孢也有一定的抑制作用。能够控制病原菌的繁殖器官形成。同时进行了液体培养基的筛选,其培养滤液对病原细菌A.t产生抑菌圈,血红铆钉菇液体菌剂及其代谢物对病原细菌抑制作用比病原真菌强。室内盆栽试验表明,在灭菌土上血红铆钉菇对茄孢镰刀菌引起的猝倒病有一定防效,田间处理试验效果不明显。  相似文献   
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