口服少孢节丛孢菌孢子对家畜粪便中线虫幼虫的杀灭研究

对捕食线虫性真菌——少孢节丛孢菌（Arthrobotrys oligospora）菌株进行了临床杀家畜寄生性线虫幼虫作用的研究。结果表明：培养的少孢节丛孢菌分生孢子经口饲喂动物后，对粪便中线虫幼虫的杀虫率分别可达96.3％（羊）、96．5％（牛）和97．4％（马）。说明少孢节丛孢菌菌株分生孢子可通过家畜消化道，并保持了其捕食寄生性线虫的能力。研究结果为捕食线虫性真菌的临床应用奠定了重要基础。     

捕食线虫性真菌-少孢节丛孢菌理化特性研究

研究了捕食线虫性真菌一少孢节丛孢菌(Arthrobotrys oligospora)的染色特性、分生孢子对外界理化因素的抵抗力以及菌丝对线虫第三期幼虫的吸引作用等。结果表明少孢节丛孢菌用革兰氏、瑞氏、姬姆萨氏液染色都能很好的着色；分生孢子对高温敏感，对抗生素不敏感，高浓度的氢离子或氢氧根离子能杀死分生孢子：但分生孢子耐低温，因此可用低温冷冻法保存捕食线虫性真菌分生孢子，其方法简便易行。首次解决了国内外在捕食线虫性真菌菌种保存中的难题。研究显示菌丝对线虫第三期幼虫无明显吸引力。     

高原地区少孢节丛孢菌超微结构观察

采用玉米粉琼脂培养法,从高原地区(海拔2 000~3 000 m)土壤分离得到一株捕食线虫性真菌,根据其菌丝形态、分生孢子和捕食器官形态等结构特征,鉴定其为少孢节丛孢菌(Arthrobotrys oligospora)。为了进一步了解少孢节丛孢菌形态学特征,对少孢节丛孢菌进行了超微结构观察,结果发现该菌有隔膜,主干菌丝上隔的分布较密集,分布距离不等,分生孢子梗不分支。菌环是由瘤状突起延伸形成弧形而形成,多个菌环接连形成菌网,线虫幼虫是被捕食器菌环或菌网捕获致死。     

捕食线虫性真菌--少孢节丛孢菌体外杀寄生性线虫幼虫的研究

对捕食线虫性真菌——少孢节丛孢菌(Arthrobotrys oligospora)菌株体外粪便捕杀马寄生性线虫幼虫进行了研究。结果表明：菌株可以在体外粪便中发育并发挥其捕食作用。在实验室条件下，其对寄生性线虫第一、二期幼虫的作用与对第三期幼虫的作用相比较．捕获致死速度快。菌株对马粪便中线虫幼虫的杀虫率高达98．7％；与对照组相比有显著差异。而且加入粪便的分生孢子数量在达到一定阈值后，再加入分生孢子，则杀虫率不再增加。此结论对捕食线虫性真菌今后临床的应用具有实际指导意义。     

新疆乌鲁木齐地区捕食性真菌圆锥节丛孢菌的分离鉴定

为了给动物线虫病的防治工作提供适应本地生存的候选捕食性真菌菌株，对新疆乌鲁木齐地区采集的土壤进行筛选，采用土壤撒布法，以秀丽隐杆线虫(Caenorhabditis elegans)作为诱饵线虫对土壤中的捕食性真菌进行分离鉴定，成功分离出具有捕食线虫功能的真菌1株。通过形态学观察，该菌捕食器官为黏性菌网，分生孢子无色，呈圆锥形，中央有一分隔，形态结构与节丛孢属相符。分子生物学分析显示，该分离株的ITS2基因序列与圆锥节丛孢菌(Arthrobotrys conoides)的同源性为99%～100%,判定该菌为圆锥节丛孢菌的新疆分离株。在实验室条件下，利用该菌株进行捕食线虫活力测定，结果发现该菌株在CMA培养基中对马圆形线虫三期幼虫的捕食率为97.47%,具有较强的捕食效率，可作为新疆地区动物线虫病生物防治工作的候选菌株。     

新疆石河子地区捕食线虫性真菌的分离鉴定

以山羊捻转血矛线虫第三期幼虫作为诱饵线虫,利用撒布分离法对新疆石河子地区土壤中的捕食线虫性真菌进行分离,并对所分离的捕食线虫性真菌进行了形态学及分子生物学鉴定.结果成功分离出了9株捕食线虫性真菌,其形态学符合少孢节丛孢菌.将分离株5.8S rDNA和ITS2基因序列与国内外已知少孢节丛孢菌菌株的对比分析,证明少孢节丛孢菌新疆分离株具有区域性特征,其捕食活性高于报道的菌株.分离出适合本地区生态环境的当地菌株对以后家畜线虫病的生物防控尤为必要.     

捕食线虫性真菌——少孢节丛孢菌CIMH1株捕食特性研究

本研究首次对国内土壤中分离出的捕食线虫性真菌—少孢节丛孢菌ＣＩＭＨ１株（Ａｒｔｈｒｏｂｏｔｒｙｓｏｌｉｇｏｓｐｏｒａｓｔｒａｉｎ：ＣＩＭＨ１）捕食马线虫第３期幼虫的活性、效力及杀虫机理进行了试验。结果表明菌株生长环境对其捕食活性有很大影响。在２０℃、有氧条件、玉米粉浓度相对较低（０．４ｇ／Ｌ）、菌丝生长较稀疏的ＣＭＡ培养基中,捕食活性最佳。捕食线虫时,在虫体运动刺激及虫体内部某些物质诱导下,菌株会产生一些特殊捕食性结构,如粘性菌丝（Ｓｔｉｃｋｙｂｒａｎｃｈｅｓ）、粘性菌环（Ｓｔｉｃｋｙｒｉｎｇｓ）和粘性菌网（Ｓｔｉｃｋｙｎｅｔｗｏｒｋｓ）等。通过这些功能性构造,菌株将线虫捕获并杀死消化。少孢节丛孢菌ＣＩＭＨ１株在最佳条件下,对马线虫第３期幼虫的平均捕食效力为７８．１５±３．８％。     

少孢节丛孢菌超微结构的观察研究

观察了捕食线虫性真菌——少孢节丛孢菌的超微结构，以探讨捕食线虫性真菌的杀虫机理。结果显示，少孢节丛孢菌属于隔膜类真菌，隔膜中央有孔，菌丝细胞一般呈长形竹节状；菌株的捕食器为黏性菌环和菌网，形成捕食器的菌丝细胞结构不同于一般的营养菌丝，胞质中含有许多电子密集体，呈大小不等的黑色类圆形颗粒状，多数排列在捕食器菌丝细胞的边缘区域，这是捕食线虫性真菌捕食器菌丝细胞的一个重要特征。     

节丛孢属食线虫真菌对体外奥斯特线虫幼虫的捕食效果

本文在国内首次报道了几株节丛孢菌食线虫真菌（５株寡节丛孢菌和２株葡萄串状节丛孢菌）在体外对山羊奥斯特线虫第３期幼虫的捕食效果。结果表明：７株真菌对奥斯特线虫幼虫的捕获率分别在７５．０％￣９６．４％之间,具有较高的捕杀线虫能力,食线虫真菌对线虫的作用方式主要是通过在线虫周围形成菌网。     

少孢节丛孢菌的分离鉴定及捕食线虫活性研究

为研究新疆地区捕食线虫性真菌的生物活性,本实验采用玉米粉琼脂培养基(CMA)培养分离自新疆不同地区的捕食线虫性真菌,通过对分离株纯培养物的形态学观察和18S rDNA基因序列分析,鉴定4株少孢节丛孢菌,分别命名为XA3、XA6、XD1和XD4。18S rDNA基因遗传进化分析表明,XA3、XA6、XD1和XD4新疆分离株之间同源性较高,与GenBank登录的少孢节丛孢菌CBS289.82株同源性最高,分别为99.6%、99.5%、99.1%和98.9%,与形态学鉴定结果一致。捕食线虫活性测定试验表明,4个分离株在CMA中的捕食率为92.8%～97.6%;体外对绵羊粪便中线虫幼虫的捕食率为90.7%～95.4%,均具有很强的捕食活性。本研究为研究绵羊消化道线虫生物防控制剂奠定基础。     

捕食线虫性真菌18S rDNA基因序列与种系发生关系研究

对捕食线虫性真菌——少孢节丛孢菌A1分离株(Arthrobotrys oligospora A1)的18S rDNA基因序列进行了研究。结果表明：其18S rDNA全基因序列为1769bp，在进化树上与同种国外分离株A．oligospora var oligospora 1最为接近，同源性为94．7％。这与二者都具有捕食性结构—菌网的特点相一致。证实捕食线虫性真菌的捕食性结构与捕食线虫性真菌种系发生有关。从少孢节丛孢菌3个分离菌株(Arthrobotrys oligospora A1、A．oligospora 1、A．oligospora2)的进化树及同源性来看。不同国家地区的丛孢菌属(Arthrobotrys)分离株确实存在差异。     

Efficacy of an Arthrobotrys oligospora N mutant in nematode-trapping larvae after passage through the digestive tract of sheep

For oral applications, biocontrol of animal parasitic nematodes in ruminants, ion beam implanted nematode-trapping fungi must have the capacity to survive the passage through the digestive tract and be efficient in reducing infective larvae of nematodes in the faeces.Ion beams induced mutation in the spores of nematode-trapping Arthrobotrys oligospora. Mutants with genetic stability were bred. The fungi were cultured in bottles with corn kernels as growth media, and spores of different doses were, respectively, administered orally to each group of sheep naturally infected with gastrointestinal nematodes. The control group did not receive fungi. The faeces of these experimental animals were collected and faecal cultivations carried out. The fungal germination, growth, reproduction and predation of livestock parasitic nematode larvae were tested in laboratory. The efficacy of an A. oligospora N mutant in nematode-trapping larvae after passage through the digestive tract of sheep was tested. The results indicated that the ion beam implantation induced mutation of the nematode-trapping fungi is a positive mutation. The mutant spores through the digestive tract of sheep can kill livestock parasite nematode larvae in vitro. These results indicate the potential of the A. oligospora N mutant as a biological control agent for sheep nematodes.This study showed that such biotechnology could be explored for improving the effectiveness of the use of fungal infections to control livestock parasitic nematodes. This work represents the first application of nematode-trapping fungi in eukaryotic microorganisms.     

Induction of nematode-trapping organs in the predacious fungus Arthrobotrys oligospora (Hyphomycetales) by infective larvae of Ostertagia ostertagi (Trichostrongylidae)

Laboratory experiments were designed to study the influence of temperature, concentrations of nematodes, oxygen tension, light, and nutrient levels, on the induction of nematode-trapping hyphal nets in the predacious fungus Arthrobotrys oligospora. When induced by infective Ostertagia ostertagi larvae, a maximum number of nets was produced at 20 degrees C, at which temperature nets in surplus were produced at larval concentrations up to 1,000 larvae per cm2. A. oligospora did not produce nets in an anaerobic atmosphere containing 21% CO2 (v/v), and net induction was suppressed to a certain degree by exposure to light. The composition of the medium had an important influence on the saprophytic growth and the net-forming capability of A. oligospora as a maximum number of nets was induced at a relatively low concentration of corn meal supporting the relatively sparse mycelium. It was shown that a proportion of trapping nets in A. oligospora maintained their trapping potential for more than 7 weeks when the temperature was below 25 degrees C. Induction of nematode-trapping organs in A. oligospora is discussed in relation to control of infective nematode parasite larvae in cow pats.     

The ecology of nematode-trapping hyphomycetes in cattle dung from three plateau pastures

This paper investigated the influence of season and altitude on the occurrence of nematode-trapping fungi in cattle faeces. Six hundred and sixty samples of cattle faeces deposited on three plateau pastures with different altitudes in the west of Yunnan Province, China, were examined in 2004. A total of 17 species of nematode-trapping hyphomycetes were isolated from these samples. The predominant species from all three plateau pastures were Arthrobotrys oligospora, A. musiformis, Monacrosporium ellipsosporum, and M. thaumasium. Species with adhesive networks were the most frequently isolated. Overall, species diversity index was negatively correlated with altitude and was different among seasons within the same site. Levels of diversity were highest in the summer, followed by autumn, spring, and winter. The conidia of the hyphomycetes isolated here germinated normally on medium containing cattle faeces, with species developing adhesive networks having the highest rate of germination. However, the rate of conidial trap (CT) formation was lower in species with adhesive networks than those in other species.     

少孢节丛孢菌捕食器表面聚合物的诱导与提取方法研究

为研究捕食线虫性真菌——少孢节丛孢菌(Arthrobotrys oligospora)捕食器表面聚合物的生化性质与作用,建立一种高效的表面聚合物诱导与提取方法尤为关键。试验首先用大豆蛋白胨液体培养基在氨基酸诱导作用下,产生大量含捕食器菌丝,然后分别用了5种不同化学性质溶液提取表面聚合物,经透析和浓缩后,测定了其中蛋白质的含量及其对线虫幼虫的毒性作用,同时还进行了提取液对真菌菌丝生长及其捕食作用的研究。通过综合分析得出,用5 mol/L LiCl溶液提取表面聚合物最为有效,其提取的表面聚合物溶液对线虫没有明显的杀线虫活性,但与捕食性真菌黏附捕获线虫过程密切相关;并通过比较源自含捕食器菌丝和普通营养菌丝的表面聚合物物质之间的差别,找到了参与黏附捕获线虫过程的物质,这为今后深入开展对捕食线虫性真菌表面聚合物的研究,进而阐明其作用机理提供了有价值的资料。     

内蒙古红豆草黄萎病菌的分离鉴定及其生物学特性

依照柯赫氏法则,利用形态学结合分子生物学的方法首次对内蒙古自治区呼和浩特市中国农科院草原研究所沙尔沁基地红豆草疑似黄萎病的病样进行分离和鉴定,利用蘸根接种法对病原菌的致病性进行测定。同时,首次在室内条件下对病菌的生物学特性,如生长最适温度、酸碱度以及碳源、氮源对病原菌生长速率和产孢量的影响进行了研究。结果表明,引起沙尔沁基地红豆草黄萎病的病原菌为大丽轮枝孢菌,菌株具有较宽的温度和酸碱度适应范围,最适于菌株生长和产孢的温度均为25℃,最适于菌株生长和产孢的pH值范围分别为7~10和5~6。在碳源选择上,大丽轮枝孢菌在可溶性淀粉上的生长速度最快,而蔗糖最有利于其产孢。在氮源选择上,大丽轮枝孢菌在牛肉膏和L-脯氨酸上的生长速度较快,且L-脯氨酸最有利于其产孢。     

Minimal nitrogen requirements of Corynebacterium renal strains

Corynebacterium renale strain 10849 was grown in a chemically defined medium containing glucosamine, ammonium sulfate, and 5 amino acids as possible nitrogen sources. Although glucosamine was slightly stimulatory, its omission from the medium had a minimal effect on growth, and washed cells introduced into glucosamine-free medium grew readily through 10 serial transfers, demonstrating that this compound was not required for growth. Individual omissions of isoleucine, valine, methionine, and glutamine resulted in lengthened lag periods and reduced growth rates in initial transfers, but recovery occurred in subsequent serial transfers so that by the 3rd or 4th transfer, growth rates and cell crops were only slightly less than in control cultures in complete medium. Omission of cystine resulted in a permanently low growth rate and reduced cell crop, but this was remedied by substituting various nonnitrogenous compounds containing reduced sulfur. Strain 10849 and 6 additional strains were then serially cultured in a minimal defined medium in which sodium thioglycolate provided reduced sulfur and ammonium sulfate served as sole nitrogen source. Since only ammonium ion was required as the nitrogen source, it could be concluded that C renale, which rapidly hydrolyzes urea, should find an adequate source of nitrogen for growth in the urinary tract of animals.     

食动物线虫真菌的分离和鉴定I.从土壤中分离捕食线虫真菌

以山羊捻转血矛线虫第三期幼虫作为诱饵线虫,利用撒布分离法,对土壤中的食线虫真菌进行了分离和鉴定。结果从不同的土样中分离到了棣属于２个属,７个种的２６株捕食线虫真菌。７个真菌种分别为寡孢节丛孢菌（Ａｒｔｈｒｏｂｏｔｒｙ ｏｌｉｇｏｓｐｏｒａ）,指状节丛孢菌（Ａ．ｄａｃｔｙｌｏｄｅｓ）,蠕虫节丛孢菌（Ａ．ｖｅｒｍｉｃｏｌａ）,圆锥节丛孢菌（Ａ．ｃｏｎｏｉｄｅｓ）,白色单顶孢菌（Ｍｏｎａｃｒｏｓｐｏｒｉ