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1.
对新疆草地饲用植物霜霉菌进行了系统的分类研究,自新疆124份草地饲用植物霜霉菌标本上共鉴定了6属37种霜霉菌,分别寄生于14科42属的63种寄主植物,其中新种2个,新变种2个,新寄主记录10个,国内新记录种8个,从生物多样性保护和生态系统的观点出发,对新疆草地饲用植物及其霜霉菌的分布,栽培牧草与天然草地野生植物霜霉病的发生,流行程度进行了讨论。  相似文献   

2.
新疆草地药用及毒害植物的霜霉菌研究   总被引:2,自引:0,他引:2  
对新疆草地药用植物及有毒有害植物的霜霉进行了系统的分类研究,采自新疆天山及平原绿洲的97份草地药用及毒害植物霜霉菌标本,共鉴定出分别寄生于15科36属44种寄生植物上的5属34种霜霉菌,包括2个新种,7个全国新记录种有5个新寄主记录,其中寄生于26属34种草地药用植物上的霜霉菌5属25种,寄生于10属11种草地毒害植物上的霜霉菌2属10种,从生物多样性的保护和持续利用及生态系统的角度出发,在挖掘我  相似文献   

3.
孟有儒 《草业科学》2003,20(4):40-42
经调查,甘肃12种菊科牧草上发生霜霉病,由盘霜霉属的7个种、轴霜霉属1个种和首次在甘肃发现的类霜霉属2个种侵梁所致,并发现鉴定盘霜霉新组合种和变种各1个。霜霉病一般在河西地区较陇东、陇南发病严重,有的发病率高速40%以上。  相似文献   

4.
孟有儒 《草业科学》2004,21(1):22-23
甘肃紫草科Boraginaceae牧草上发现5种霜霉菌,寄生危害6种植物.除微孔草霜霉病发病率达15%以上外,其他均为零星发生.  相似文献   

5.
(一)霜霉病 牧草的霜霉病是由霜霉菌引起的,主要侵染豆科牧草如苜蓿、三叶草、草木樨等。该病发生的基本规律是病菌以菌丝侵染病草植株的地下器官越冬或者以卵孢子在病组织内越冬;翌年春季随植株生长,在地上产生孢囊孢子,侵染其他植株。致病菌主要危害牧草的叶部,病株叶子顶部萎黄,病叶向背方卷曲,叶背面生出淡紫色的  相似文献   

6.
甘肃唇形科、茜草科牧草霜霉病调查研究   总被引:1,自引:1,他引:0  
孟有儒 《草业科学》2004,21(10):54-55
报道了甘肃唇形科牧草上发生的5种霜霉菌,其中霜霉属 3种,轴霜霉属 1种,假霜霉属 1种.茜草科牧草上只发现霜霉属 2种,其中拉拉藤霜霉Peronospora galii是我国新记录种.  相似文献   

7.
正本刊讯(特约通讯员钱开胜)近日,广西作物遗传改良生物技术重点开放实验室发布消息,由广西农业科学院重点实验室葡萄分子设计育种团队与中国农业大学、北京理化测试中心、上海交通大学等单位合作,率先完成了葡萄霜霉菌全基因组遗传密码的破译工作,该研究成果已发表在国际有关刊物上,广西农科院重点实验室为该项目第一完成单位。据悉,葡萄霜霉病属鞭毛菌亚门,卵菌纲霜霉目,单轴霉属,是葡萄主要病害之一,1834年在美国野生葡萄  相似文献   

8.
木霉对草坪上2种重要土传病害生防效果的研究   总被引:8,自引:0,他引:8  
利用木霉菌Trichoderma spp.防治草坪上2种重要的土传病害--褐斑病及镰刀枯萎病.木霉菌对草坪上的植物病原真菌室内抑菌效果及木霉制剂温室和田间防效试验结果表明,在拮抗作用测定中,木霉菌对草坪镰刀枯萎病菌和立枯丝核病菌具有较强的拮抗作用,拮抗机制主要为竞争作用、重寄生作用和抗生作用;温室盆栽及田间防治试验结果表明,木霉对镰刀枯萎病的防效分别为85%和74%,木霉对立枯丝核病菌的防效分别为86%和76%,且具有防效持久、刺激植物生长的作用.  相似文献   

9.
杀菌剂拌种防治草坪草病害的研究进展   总被引:3,自引:0,他引:3  
综述了国内外用杀菌剂拌种防治草坪草病害的研究进展.现已报道,早熟禾、黑麦草和高羊茅3属草坪草常见的种带与土传真菌病害14类,病原真菌54种;其中最常见的包括立枯丝核菌、德氏霉、腐霉、镰刀菌、细交链孢和壳针孢等.常用杀菌剂福美双、甲基硫菌灵、三唑酮和甲霜灵等对草坪草主要病原真菌的室内防效明显,其中对福美双反应极敏感的病原真菌有禾谷德氏霉,对甲基硫菌灵反应极度敏感的病原真菌有禾顶囊壳、粉红粘帚霉和瓶霉菌等,对三唑酮反应敏感的真菌有串珠镰孢、禾顶囊壳、结缕草锈菌、颖枯壳针孢和立枯丝核菌,甲霜灵主要对腐霉有效.田间条件下杀菌剂拌种可提高草坪草种子发芽率和田间出苗.杀菌剂拌种时要尽量避免在防治一种病害的同时,可能会导致另一种原本不重要病害的大发生.杀菌剂应向着在植物体内、土壤、大气和水体中无残留或有微量残留也可以在短期内降解,生成无毒天然物质而向完全融入大自然的方向发展,这是草地农业生态系统可持续发展的一种必然趋势.  相似文献   

10.
霜霉病是南方葡萄产区五大病害之一,特别是近几年来南方推广大棚促成栽培及避雨栽培,揭膜后是葡萄霜霉病害极易侵染之时,侵害葡萄轻则削弱树势,影响果实品质,重则提早落叶,影响花芽分化,直接造成来年产量降低。1 病害症状 被害叶片开始为半透明油渍状病斑,淡黄至红褐色。发病4~5天后,病斑部位反面形成密集白色霜似物;继后叶片失水焦枯早落,新梢侵害后上端肥厚弯曲,白色,最后变褐色枯死;幼嫩果实侵染后果皮变灰色,表面布满霜霉。2 发生规律 霜霉病是专性寄生菌,在被寄生的葡萄组织细胞间繁殖。病菌主要以卵孢子在病残组织(以病叶为主)中…  相似文献   

11.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

12.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

13.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

14.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

15.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.  相似文献   

16.
17.
An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.  相似文献   

18.
Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein  相似文献   

19.
正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments in  相似文献   

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