柑橘溃疡病拮抗芽孢菌株的筛选及其控病作用

从柑橘根际土壤中获得192个细菌分离物,通过平板拮抗测试,筛选出对柑橘溃疡病菌（Xanthomonas axonopdis pv. citri）有较强拮抗作用的6个芽孢菌株,抑菌圈直径达12.0～25.0mm,其中菌株G32对柑橘溃疡病菌抑制效果最好,稳定性高;温室控病试验表明,菌株G32的控病效果最佳,提前喷施拮抗菌其预防效果达60.7%,接种溃疡病菌后喷施的治疗效果为53.2%;根据其形态特征、培养性状、生理生化特性及16S rDNA序列比对分析,将G32鉴定为枯草芽孢杆菌Bacillus subtilis。     

一株桑树内生拮抗菌的分离鉴定

从经过严格表面消毒的桑树根、茎、叶中分离获得内生细菌76株。以金黄色葡萄球菌(Staphylococcus aureus)作为指示菌进行拮抗菌的筛选,其中5个分离株具有抑菌活性,复筛选出抑菌活性及热稳定性最强的G21菌株。进一步研究表明G21菌株对家蚕病原真菌球孢白僵菌(Beauveria bassiana)、绿僵菌(Metarhizium)均具有较强的拮抗作用。该菌株的形态及部分生理生化特征为:革兰阳性,杆状,产芽孢,接触酶阳性,好氧。16S rDNA序列分析表明该菌株与芽孢杆菌(Bacillus)的同源性达到99.8%。综合以上鉴定结果确定G21菌株为芽孢杆菌。     

火龙果茎腐病拮抗细菌的筛选和鉴定

摘要：寻找1-2株对火龙果茎腐病具有拮抗作用的细菌菌株。通过对黑龙江、江苏、浙江、海南等地的土壤中的细菌进行分离纯化,得到细菌菌株206株。采用平板对峙法筛选出对火龙果茎腐病菌具有强烈拮抗作用的菌株1株,PCY－67。菌株能够显著抑制火龙果茎腐病菌菌丝生长,抑菌圈直径分别可达30mm。通过形态特征、生理生化特性及16S rDNA序列同源性比较,鉴定该菌株均为类芽孢杆菌（Paenibacillus polymyxa Ash, Priest & Collin）。     

香蕉枯萎病拮抗内生细菌的筛选及鉴定

对健康香蕉植株体内的内生细菌进行了分离纯化,得到63株内生细菌菌株。采用平板对峙法筛选出2株对香蕉枯萎病具有强烈拮抗作用的菌株。这两株菌均能够显著抑制FOC菌丝生长, 抑菌率均在55%左右。通过生理生化、形态特征及16S rDNA序列同源性比较,鉴定均为枯草芽孢杆菌（Bacillus subtilis）。     

奇异根串珠霉菌拮抗放线菌的筛选与鉴定

本实验以奇异根串珠霉菌（Thielaviopsis paradoxa）为目标菌,通过平板梯度稀释法从槟榔根系土壤中分离获得放线菌,利用平板对峙法筛选对奇异根串珠霉菌具有抑菌活性的菌株,并通过发酵液复筛出4株抑制效果达90%以上的菌株,编号为D2-3、G1-12、D2-9和G9-4。通过培养特征、形态特征、生理生化特性及16S rDNA序列分析对抑制率99.76%的菌株D2-3进行分类鉴定,初步鉴定该菌株为一株链霉菌,与桑树链霉菌（Streptomyces samsunensis）16S rDNA序列相似性为99.41 %。     

两株紫花苜蓿根际芽孢杆菌的筛选及生防效果研究

从紫花苜蓿根际土中分离出2株芽孢杆菌(Bacillus spp.)菌株CYY-6和CYY-42,并评价了其对尖孢镰刀菌(Fusarium oxysporum)的抑制作用,及其对由尖孢镰刀菌引起的苜蓿根腐病的防治效果。经过形态观察、16S rDNA序列分析和生理生化鉴定,确定菌株CYY-6为地衣芽孢杆菌(Bacillus licheniformis),CYY-42为短短芽孢杆菌(Brevibacillus brevis)。同时检测发现这2株芽孢杆菌均能不同程度地合成嗜铁素。在平板对峙实验中,2株菌株均能对尖孢镰刀菌产生拮抗作用,并产生抑菌带,抑菌率分别为49.3%和56.3%。且其发酵液可以致使尖孢镰刀菌菌丝及孢子生长异常,出现菌丝扭曲、断裂、破碎,孢子数量明显减少等现象。在盆栽实验中,2株菌株对由尖孢镰刀菌引起的紫花苜蓿根腐病的相对防效分别为57.55%和64.03%,在紫花苜蓿根腐病防治方面具有较好的应用潜力。     

圆孢芽孢杆菌A95的分离与鉴定

从茶树根际土壤中分离获得一株对多种家蚕病原真菌具有强烈拮抗作用的细菌。经培养特征观察以及生理生化指标测定、16S rDNA碱基序列测定和同源性分析,鉴定该菌株为圆孢芽孢杆菌,定名为Bacillus globisporusA95。该菌株的16S rDNA序列已在GenBank注册(登记号:AY387584)。     

番茄细菌性叶斑病菌的拮抗菌筛选、鉴定及其拮抗性能评价

采用含菌平板抑菌圈测定法,从120株高寒草地牧草内生细菌中分离筛选到一株对番茄细菌性叶斑病拮抗能力较强的菌株264ZY7,其抑菌圈直径为1.22 cm。264ZY7菌体短杆状,大小为1.534 μm×0.571 μm~3.210 μm×0.781 μm,革兰氏阳性菌,根据形态特征,并结合16S rDNA和gyrB基因序列相似性分析,将菌株264ZY7鉴定为解淀粉芽孢杆菌Bacillus amyloliquefaciens。通过室内盆栽防效试验,结果表明该菌株对番茄细菌性叶斑病的防效达69%,此外,该菌株对8种病原真菌具有抑菌能力,说明抑菌谱较宽,且抑菌率均大于30%,对番瓜根腐病菌(Fusarium sp.)效果最明显,抑菌率为52.84%。该研究结果为高寒草地紫花针茅内生细菌264ZY47的进一步开发利用提供了依据。     

三株优良促生菌的16S rDNA序列初探

百脉根根际分离出根瘤菌2株(LC15、LC20)与白三叶根际中分离出根瘤菌RW183基因组DNA经PCR扩增16S rDNA序列、阳性克隆检测、质粒提取测序,并与GenBank中已知序列比对,结果表明,菌株LC15与LC20的16S rDNA序列与多株克雷氏菌属(Klebsiella sp.)的16S rDNA核苷酸序列的同源性均超过99.00%,RW18与勒克氏菌属中的Leclercia adecarboxylata (HQ242722)核苷酸序列同源性为99.79%,结合各菌株的主要生理生化特征,将菌株LC15与LC20初步鉴定为Klebsiella sp.,将菌株RW18鉴定为Leclercia sp.。     

几株桑天牛成虫肠道优势细菌的分离与鉴定

为了研究桑天牛成虫肠道微生态环境,探索破坏桑天牛营养利用等功能的生物防治新途径,对健康桑天牛成虫肠道的优势细菌进行分离鉴定。选择平皿上出现3个以上的菌落作为肠道优势细菌进行分离纯化,共获得6个菌株。6个菌株均呈杆状,革兰染色和氧化酶反应均呈阴性,在25～35℃、pH 5.5～9.5的环境中生长良好,但各菌株的菌落形态及多种生化性状有差异。通过菌体形态观察、染色反应、生理生化特征分析及16S rDNA碱基序列测定与同源性分析,鉴定1、2、3号菌株分别为产酸克雷伯氏菌(Klebsiella oxytoca)、大肠埃希氏菌(Escherichia coli)、荧光假单胞菌(Pseudomonas fluorescens),4、5、6号菌株分别属于不动杆菌属(Acinetobacter)、沙雷氏菌属(Serratia)、肠杆菌属(Enterobacter)。     

商会自治的基石——商会自治规范研究

在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

猪毛色遗传的研究进展

本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.     

不同样本商品蜂蜜中硒含量的测定

用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10～0.82μg/g。表明:蜂蜜应视为天然富硒营养品。     

乳酸杆菌益生作用机制的研究进展

乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分（表面蛋白、脂磷壁酸和肽聚糖）与肠道受体（Ｃ型凝集素受体、Ｔｏｌｌ样受体和 Ｎｏｄ样受体）,阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。     

中华人民共和国农业部公告 第267号

为贯彻落实《兽药生产质量管理规范》(简称《兽药GMP》),进一步推动兽药GMP实施进程,我部制定了《兽药生产质量管理规范检查验收办法》,现予公告。本公告自2003年6月1日起施行。附件:兽药生产质量管理规范检查验收办法二○○三年四月十日第一章 总则 第一条 为推动《兽药生产质量管理规范》(以下简称兽药GMP)的实施,规范兽药GMP检查验收工作,制定本办法。 第二条 农业部负责全国兽药GMP管理和检查验收工作;负责制修订兽药GMP检查验收管理规定;负责兽药GMP检查员队伍建设和监督管理工作,负责国际兽药贸易中GMP互认工作。 …     

鸡败血支原体垂直传播模式及其阻断方法

以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。     

Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF

Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo.