适宜黄绿木霉T1010生长培养料筛选

木霉广泛存在于土壤、根际及其它基质中,对植物土传病原真菌具有拮抗作用。扩大生防因子黄绿木霉(Trichoderma aureoviride)T1010培养料范围是利用生产地资源扩大生产、大面积应用的前提。本试验通过测定黄绿木霉T1010的菌丝生长和分生孢子生长,黄绿木霉T1010在固体基本培养基上生长,最佳碳源为淀粉;优化了培养条件,确定最适宜种子培养用PD培养基,摇瓶培养,生长时间3d后,菌丝生长量为5.75g/ml;最经济适宜扩大培养基为玉米15g/L,豆粉5g/L,摇瓶培养3d后,菌丝生长量为5.83g/ml;最适宜的、经济的固体发酵培养基为麦麸∶醋渣∶水=2∶1∶3.3,发酵产物孢子量为2.46×1010cfu/g。本文研究确定黄绿木霉T1010腐解培养料的能力为多方面扩大生产黄绿木霉制剂提供了科学依据。     

基于响应面法优化莱氏绿僵菌SZCY200812的液相发酵条件

为提高莱氏绿僵菌菌株SZCY200812液相发酵时孢子萌发率和生物量，为固相发酵产孢提供高质发酵液，本研究采用单因素及Box-Behnken试验设计结合的方法对该菌液相发酵过程中培养液种类、装液量、pH、摇床转速及培养温度等条件进行优化，确定最佳的液相发酵培养条件。结果表明，通过单因素试验初步确定利用SDY培养液、装液量100/250mL、pH7、摇床转速180r/min及温度25℃，第120h每10mL液态发酵生物产量为0.8433g。通过响应面法建立了莱氏绿僵菌SZCY200812液体发酵培养菌丝生物量与自变量回归模型，根据模型所得结果得出装液量为100.82/250mL，摇床转速178.85r/min，温度24.80℃，pH6.73条件下为理论最佳液态发酵培养条件。为便于生产，得出该菌株SZCY200812在SDY培养液中最佳的培养条件为：装液量101/250mL、pH6.7、摇床转速179r/min以及温度25℃，第120h每10mL液相发酵生物产量达0.8637g。综合以上结果，影响莱氏绿僵菌SZCY200812液相发酵的因素由强至弱依次为pH（D）、温度（C）、摇床转速（B）和装液量（A）。     

葡萄霜霉病菌拮抗放线菌PY-1发酵条件优化

为探讨暗黑链霉菌Streptomyces atratus PY-1液体摇瓶发酵条件,提高其活性次级代谢产物的产量,以菌体生物量和发酵液抑制葡萄霜霉病菌Plasmopara viticola活性为指标,采用单因子试验和正交试验对菌株PY-1的最适发酵培养基成分及发酵条件进行优化。结果表明,菌株PY-1最适发酵培养基为玉米粉50 g/L、葡萄糖5 g/L、蛋白胨5 g/L、氯化铵5 g/L、氯化钠 0.5 g/L;最佳发酵培养条件为培养温度28 ℃、培养时间5 d、初始pH 7.0、250 mL三角瓶装液量90 mL、接种量体积分数5%、摇床转速180 r/min。在最佳发酵培养基和培养条件下,菌株PY-1发酵液抑菌率达到99.26%,抑菌能力提高8.35%。     

木耳菌糠培养球孢白僵菌的条件筛选及优化

白僵菌是一种虫生真菌,目前在农林害虫防治中取得了明显的效果。为了进一步促进白僵菌农药的发展,开发低成本的白僵菌发酵方法或优化其发酵条件是不可缺少的一环。本文尝试以木耳菌糠作为主要培养基液体发酵球孢白僵菌,通过单因素试验和正交试验确定菌糠培养基配方并优化发酵条件。结果表明,废弃菌糠适宜作为球孢白僵菌的主要培养基,当料液比为1:4,补充0.3%硫酸锰、0.5%硝酸铵,接菌量10%,培养温度为25 ℃,培养时间为4 d时,球孢白僵菌的产孢量达到了2.0×10⁹个孢子/mL。研究证实了木耳菌糠培养球孢白僵菌的可行性,希望为低成本发酵其他生防菌提供新思路。     

木霉Tr-92菌株厚垣孢子发酵条件的优化

利用单因素试验、正交试验方法对木霉Tr-92厚垣孢子发酵培养基及培养条件进行优化,筛选获得了适合此菌株厚垣孢子产生的最佳培养基组成为:草炭2.5%,玉米浆4.5%,葡萄糖2%,酵母膏0.5%;最佳培养条件为:接种量3%,装液量75mL/250mL,转速为180r/min,初始pH 5.0,温度28℃,培养时间7d。在此培养条件下,木霉Tr-92菌株厚垣孢子产量达到3.01×108个/mL。与优化前相比,厚垣孢子产量增长130.80%。通过培养条件优化确定了适合木霉Tr-92菌株产生厚垣孢子的条件,为高效木霉厚垣孢子生防菌剂的研制奠定了基础。     

‘赞皇枣’黑腐病菌拮抗芽胞杆菌的筛选及发酵条件优化

以‘赞皇枣’黑腐病主要病原菌链格孢菌［Alternaria alternata (Fries) Keissler］为靶标,对具有较强抗真菌活性的10株芽胞杆菌进行室内多重筛选,并采用二次回归正交旋转设计和单因素试验对筛选获得的目标菌分别进行发酵培养基优化和最佳发酵条件确立。结果表明：芽胞杆菌B07对靶标菌拮抗作用良好,活体拮抗抑菌带宽度达(8.00±0.50)mm,无菌发酵滤液抑菌圈直径为(24.44±1.37)mm,且有良好的持久性,具有开发应用价值;B07发酵的最优培养基为：红薯粉2 g/L,牛肉膏10 g/L,NaCl 10 g/L,MnSO4 ?0.02 g/L;最佳发酵条件为：种子液浓度1.5×107~2.0×108 cfu/mL时,接种量5%（V/V）,装液量40 mL/250 mL,原始pH7.0,发酵温度32 ℃,时间72 h。     

贝莱斯芽胞杆菌YL2021高产嗜铁素的摇瓶发酵工艺优化

贝莱斯芽胞杆菌Bacillus velezensis YL2021是一株对多种植物病原菌具有良好防治效果的生防菌,其基因组中含有完整的儿茶酚型嗜铁素合成基因簇,在缺铁条件下能产生具有抑菌作用的嗜铁素。为了提高贝莱斯芽胞杆菌YL2021嗜铁素的产量,采用摇瓶培养发酵,通过Plackett-Burman(PB)试验、中心组合试验(central composite design,CCD)和响应曲面法(response surface methodology,RSM)分析,优化菌株YL2021高产嗜铁素的发酵培养基成分和培养条件。结果表明,菌株YL2021高产嗜铁素的最优培养基配方：葡萄糖19.43 g/L、NH₄Cl 1.93 g/L、KH₂PO₄ 9.02 g/L、谷氨酸钠6.00 g/L、Mg SO₄ 1.75 g/L和Ca Cl₂0.08 g/L;最优培养条件为：温度30℃、初始p H值7.0、接种量5%、培养时间36.5 h、转速200 r/min和装液量75 m L(25...     

对斜纹夜蛾高致病性莱氏野村菌Nr19固体培养条件的优化

经前期生物测定,莱氏野村菌Nomuraea rileyi(Nr19)菌株能使斜纹夜蛾Spodoptera litura(Fabricius)幼虫大量感病及死亡,为了提高分生孢子产量,本文采用单因素试验,对影响菌株Nr19生长的固体发酵工艺条件进行了优化。结果表明,大豆与麦麸混合物是菌株Nr19的理想发酵基质,适量麸皮的加入,能有效提高产孢量。培养期间温湿度的分段控制对产孢的影响也较大。优化后的培养条件为:大豆、麸皮混合比例为85:15,液体种子种龄5 d,接种量15.0%,连续光照,期间控制前3 d相对湿度为85%,之后降为60%,而培养温度则采用前2 d与后11 d保持在25℃,中间升温至28℃的分段控温方式培养16 d。此条件下产孢量比优化前提高近2倍,为(6.045±0.061)×10⁹孢子/g,而活孢率可达(93.770±0.278)%,可为后续高侵染力杀虫制剂的研究提供较充足的试验材料。     

响应面法优化贝莱斯芽胞杆菌YC11的液体发酵培养基

为提高对烟草黑胫病具有良好防治效果的贝莱斯芽胞杆菌Bacillus velezensis YC11菌株的芽胞产生水平,通过Plackett-Burman试验筛选出影响YC11摇瓶发酵芽胞产量的3个显著因子：玉米粉、酵母粉和硫酸镁;再结合最陡爬坡试验、Box-Behnken(BB)响应面法拟合显著因子与芽胞产量的非线性方程求解,得到优化的YC11菌株发酵产胞培养基配方。结果表明,优化后的最佳配方为玉米粉13.74 g/L、鱼粉15.00 g/L、酵母粉15.73 g/L、玉米浆5.00 g/L、硫酸镁0.59 g/L和磷酸二氢钾0.30 g/L,此时模型预测发酵液芽胞最佳产量为114.4亿芽胞/m L,验证值为116.6亿芽胞/m L,预测值与验证值之间吻合较好,较优化前芽胞产量（70.8亿芽胞/m L）提高了64.7%。采用500 L发酵罐进行发酵验证,菌株YC11的芽胞产量为150亿芽胞/m L。盆栽试验结果表明,菌株YC11发酵液对烟草黑胫病的防效可达到100%。     

八角炭疽病生防菌株筛选及发酵条件研究

为获得八角炭疽病高效生防菌, 利用组织分离法从八角叶片分离出芽胞杆菌菌株, 通过与八角炭疽病病原菌哈锐炭疽菌Colletotrichum horii对峙培养筛选出拮抗菌株L0517?利用拮抗菌株的发酵滤液来验证其对八角炭疽病的防治效果, 并研究菌株的发酵条件?结合形态学?生理生化及 16S rDNA 和 gyrB序列分析, 将菌株L0517鉴定为贝莱斯芽胞杆菌Bacillus velezensis?菌株L0517发酵滤液可显著抑制哈锐炭疽菌菌丝生长, 并引起菌丝形成囊泡状结构?用含0.1%吐温-80和10% L0517发酵滤液处理八角叶片可显著降低哈锐炭疽菌的致病能力, 且对八角安全无致病性?发酵条件研究表明, 当发酵温度为25℃, 培养液pH为7, 碳源和氮源分别为麦芽糖和酵母粉时菌株生长最快, 其发酵液的抑菌活性也最强?     

Investigation of the Mode of Action of Nematode Neuropeptides

The neuropeptide AF2 has a complex set of actions on the dorsal muscle strip of Ascaris suum, including a potentiation of the acetylcholine-stimulated muscle contraction. Caffeine at 100 μm and 5 mm inhibited this potentiation, as did 100 μm theophylline in two out of six studies. The cyclic-AMP-potentiating compounds IBMX, dibutyryl cAMP and forskolin had no effect on the AF2-induced potentiation of the acetylcholine-stimulated muscle contraction. These preliminary data suggest that the potentiating action of AF2 is not mediated by a cAMP pathway.     

厚朴病虫害种类的初步调查

采用标准地法和线路调查法,对湖北恩施市新塘乡双河厚朴基地的厚朴病虫害进行了系统调查,记录主要虫害13种,其中叶部害虫9种,枝干害虫2种,根部害虫2种。厚朴主要病害5种。藤壶蚧、厚朴枝角叶蜂和厚朴新丽斑蚜为湖北省首次报道,小绿叶蝉为厚朴新寄主记录种。同时记录了藤壶蚧的天敌6种,其中寄生小蜂2种,瓢虫4种;厚朴新丽斑蚜的天敌昆虫8种。对藤壶蚧、厚朴枝角叶蜂和厚朴苗木根腐病等重要病虫害的发生规律进行了初步调查,同时提出了防治建议。     

Effects of timing and method of application of Penicillium oxalicum on efficacy and duration of control of Fusarium wilt of tomato

The effects of timing and method of application of Penicillium oxalicum on the control of fusarium wilt of tomato were investigated. Application of P. oxalicum to tomato seedlings in seedbeds reduced disease caused by Fusarium oxysporum f.sp. lycopersici in a growth chamber by 45–49% and in glasshouse experiments by 22–69%. Disease suppression was maintained for 60–100 days after inoculation with the pathogen in the glasshouse. No disease reduction was observed in tomato plants where P. oxalicum was applied to seeds. Treatment with P. oxalicum did not affect the population of F. oxysporum f.sp. lycopersici in the rhizosphere.     

棉花黄萎病菌致病型的AFLP分析

 选用41个棉花黄萎病菌(Verticillium dahliae)代表菌系,在温室条件下,对4个棉花品种鄂荆1号(感)、中棉所12(耐)、文-5(抗)和唐棉2号(抗)进行致病性测定,结果可将供试菌系分为落叶型与非落叶型2类。选取8对AFLP引物PCR扩增的结果中,统计带型稳定、清晰且有多态性的条带,共169条作系统聚类分析,将上述菌系分为2大类,第一类为非落叶型菌系,包括10个非落叶型菌系和1个过渡菌系;第二类为30个落叶型菌系。根据聚类分析建立树状图,发现菌系与地理来源存在一定的相关性,而依据菌系致病力强弱分类则相关关系不大。选用25对EcoRⅠ和MseⅠ引物组合,对供试的41个V.dahliae进行AFLP扩增,筛选到2对引物E64(GACTGCGTACCAATTCGAC)、M53(GATGAGTCCTGAGTAACCG)和E49(GACTGCGTACCAATTCCAG)、M65(GAT-GAGTCCTGAGTAAGAG),能分别扩增出433bp和110bp2条仅为V.dahliae非落叶型菌系独有的特异片段,可将落叶型与非落叶型菌系分开,这2条特异片段被命名为EM₄₃₃和EM₁₁₀。     

Mode of action of etoxazole

The mode of action of the 2,4-diphenyl-1,3-oxazoline acaricide/insecticide etoxazole has been argued to be moulting inhibition, but experimental results supporting this hypothesis are lacking. This study investigated the effect of etoxazole on chitin biosynthesis in the fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae). Etoxazole induced moulting defects in fall armyworm larvae similar, if not identical, to those caused by benzoylphenylureas, a well-known class of insecticidal chitin biosynthesis inhibitors. Furthermore, in contrast to untreated larvae, the chitin content in the integuments of larvae several days after treatment did not differ from that in freshly ecdysed individuals, thus suggesting strong chitin biosynthesis inhibition in vivo. A more detailed investigation of the inhibitory potential by incubating cultured integument pieces from larvae of S. frugiperda with [14C]N-acetyl-D-glucosamine, a radiolabelled chitin precursor, revealed I50 values of 2.95 and 0.071 microM for etoxazole and triflumuron respectively. The incorporation of radiolabel into potassium hydroxide-resistant material was inhibited by etoxazole in a dose-dependent manner. Based on these results, it is concluded that the acaricidal and insecticidal mode of action of etoxazole is chitin biosynthesis inhibition.     

青稞种子带菌检测及杀菌剂消毒处理效果

为了研究青稞种子外部和内部携带真菌情况,比较不同杀菌剂对青稞种子的带菌消毒效果和对幼苗生长的影响,为青稞种子播前包衣处理和种传真菌病害防控提供依据,采用离体平皿法对云南迪庆‘云青1号’、‘云青2号’和‘短白青稞’3个主栽品种进行带菌检测,并对种子进行拌种或浸种处理测定6种杀菌剂对种子消毒效果,分析杀菌剂对种子发芽和幼苗生长的影响。结果表明:供试青稞种子表面携带的优势菌群为青霉(Penicilliumspp.)、镰刀菌(Fusariumspp.);种子内部寄藏的真菌主要为镰刀菌、核腔菌(Pyrenophoraspp.)、附球菌(Epicoccumspp.)、丝核菌(Rhizoctoniaspp.)、链格孢(Alternariaspp.)和木霉(Trichoderma spp.)。青稞不同品种的种子表面及内部携带的真菌种类差异较大。致病性测定表明,镰刀菌对种子萌发和幼苗生长影响最大,后期出现幼苗坏死现象。45%咪鲜胺EW、75%百菌清WP、50%福美双WP对青稞种子携带真菌均有显著抑制作用和消毒效果,50%福美双WP消毒效果最优,达100%;45%咪鲜胺EW、75%百菌清WP、50%福美双WP处理对青稞种子发芽和幼苗生长均无显著影响。     

黑麦草属DNA条形码鉴定技术研究

以毒麦、田毒麦、多花黑麦草、多年生黑麦草、硬直黑麦草、高羊茅与狗牙根等禾本科的7种植物为材料,拟采用 DNA 测序、特异性位点比对、种间遗传距离测定、建立系统树等分析候选 DNA 条形码 psbA-trnH 鉴别黑麦草属常见植物的能力。实验结果表明,以 psbA-trnH 为 DNA 条形码时,建立的系统发育树能较好区分毒麦和田毒麦与其他几种植物。psbA-trnH 序列可以作为黑麦草属植物的潜在条形码。     

百合地下害虫主要种类调查及生物（源）农药筛选

调查了甘肃省临洮县为害百合的地下害虫种类, 并以主要发生为害种类为供试对象, 采用拌土法测定了几种生物（源）农药对主要害虫的室内毒力和致死中时。调查发现小云斑鳃金龟Polyphylla gracilicornis、棕色鳃金龟Holotrichia titanis为主要发生及为害种类, 不同时间发生种类存在差异, 9月份以小云斑鳃金龟幼虫发生为害为主, 发生量占地下害虫总数的66.16%, 平均种群密度为10.48头/m2, 10月份, 则以棕色鳃金龟幼虫发生为主, 发生量占地下害虫总数的96.86%, 平均种群密度为7.79头/m2, 主要取食百合根系和鳞茎, 造成根系数量减少, 鳞茎出现不规则褐色缺口或凹陷斑。药剂筛选结果表明, 1.8%阿维菌素乳油、200亿孢子/g球孢白僵菌粉剂对两种蛴螬均具有较高的杀虫活性和速效性, 药后7 d时, 校正死亡率在82.22%以上, 对小云斑鳃金龟幼虫和棕色鳃金龟幼虫的LC50分别为0.161、0.060 mg/g和5.558×107、0.362×107孢子/g, LT50分别为2.237 d（2.2 mg/g）、1.393 d（2.2 mg/g）和6.645 d（40.0×107孢子/g）、4.940 d（2.0×107孢子/g）, 这两种生物（源）农药对两种蛴螬的LC50和LT50值均略大于两种化学农药25%二嗪磷乳油、40%辛硫磷乳油处理的, 且对小云斑鳃金龟幼虫的杀虫活性均低于对棕色鳃金龟幼虫的杀虫活性, 致死中时则长于对棕色鳃金龟幼虫的致死中时。     

Effects of different temperature treatments on dormancy of sclerotia of ten isolates of Sclerotium cepivorum

The variability of dormancy of sclerotia of ten isolates ofSclerotium cepivorum was investigated. Of all isolates tested, the freshly harvested sclerotia were dormant. After drying for 48 hours the sclerotia of six isolates were able to germinate, two isolates stayed dormant and two isolates were infested by hyperparasitic fungi. After storage in soil at 5°C or 20°C, the sclerotia of the different isolates exhibited considerable differences in respect to germination capability, but all isolates showed highest germination after a treatment of 8 weeks at 20°C followed by 8 weeks at 5°C. The sclerotia of all isolates showed an increased capacity to germinate withoutAllium extracts at 10°C after pretreatment at 30°C for 28 days.     

Allelopathy of buckwheat: Assessment of allelopathic potential of extract of aerial parts of buckwheat and identification of fagomine and other related alkaloids as allelochemicals

The allelopathic potential of buckwheat ( Fagopyrum esculentum ) was investigated. Field study showed that living buckwheat reduced weed biomass compared with plots without buckwheat. Laboratory study revealed that root exudates suppressed root and shoot growth of weeds and reduced weed dry weight. Sequential partitioning of the aqueous ethanolic extract of the aerial parts of buckwheat showed that the chloroform extract caused an 80% reduction in radicle elongation of lettuce seedlings at a concentration of less than 100 p.p.m. Fagomine, 4-piperidone and 2-piperidinemethanol were isolated and identified by ¹H and ¹³C nuclear magnetic resonance from the chloroform extract. These compounds caused a 50% inhibition of radicle elongation in lettuce seedlings at concentrations of less than 100 p.p.m. These results suggest that compounds 1, 2, and 3 might act as allelochemicals and affect the growth or germination of different plant species.