死亡谷芽胞杆菌NBIF-001防治番茄棒孢叶斑病研究

为明确死亡谷芽胞杆菌NBIF-001菌株对棒孢叶斑病的防治效果,采用平板对峙结合显微观察确定其对多主棒孢的抑菌活性,并采用活体盆栽试验研究该菌株对番茄棒孢叶斑病防治效果。结果表明,在平板对峙条件下NBIF-001对多主棒孢具有良好的抑菌活性,显微镜下观察到菌丝发生扭曲、肿胀和变形;盆栽试验结果表明NBIF-001对棒孢叶斑病的防治效果达到71.46%。NBIF-001和50%啶酰菌胺WG联用防治番茄棒孢叶斑病的效果明显好于单独施用50%啶酰菌胺WG,具有较明显的增效作用,化学杀菌剂50%啶酰菌胺WG对NBIF-001菌株生长无明显影响,两者具有较好的相容性。     

黄瓜棒孢叶斑病拮抗细菌的筛选、鉴定及防治效果

为开发防治黄瓜棒孢叶斑病的生防资源,从辽宁省、山东省、河北省该病害发生严重的田块根际土壤中分离和筛选生防菌株,测定所得菌株对黄瓜棒孢叶斑病菌Corynespora cassiicola的抑制活性,通过离体叶片试验、盆栽试验和田间试验,测定其防效,并利用形态学和分子生物学方法对其进行鉴定。结果显示,从30份根际土壤样品中共分离出细菌263株,对黄瓜棒孢叶斑病菌平板抑制率大于60.04%的菌株有10株,其中菌株ZF57的效果最好,抑制率为64.85%;菌株ZF57对其它7种植物病菌也有较好的抑制效果;菌株ZF57对黄瓜棒孢叶斑病的离体叶片防治效果、盆栽防治效果和田间防治效果分别达到66.67%、58.73%和62.13%,与对照药剂氟吡菌酰胺的防治效果相当;经形态学和分子生物学鉴定,菌株ZF57为解淀粉芽胞杆菌Bacillus amyloliquefaciens。     

单端孢菌素对几种作物病原菌的室内毒力及田间防效

为明确单端孢菌素对主要作物病原菌的抑菌活性和田间防效,采用孢子萌发抑制测定法、菌丝生长速率法和田间药效常规试验方法,测定了单端孢菌素在不同质量浓度下对作物病原菌的室内毒力及田间药效。结果表明:单端孢菌素对供试16个病原菌的MIC为1.9~15.5mg/L,对辣椒炭疽病菌、番茄早疫病菌、水稻恶苗病菌、水稻稻瘟病菌、番茄灰霉病菌、玉米小斑病菌和马铃薯晚疫病菌等7个病原菌的EC50分别为5.93、7.90、9.27、10.78、13.34、14.95和16.50mg/L,500mg/L质量浓度对番茄灰霉病、番茄早疫病、辣椒炭疽病、马铃薯晚疫病、玉米小斑病和水稻稻瘟病的防治效果分别为78.98%、81.29%、85.28%、72.42%、78.99%和72.74%。单端孢菌素具有较强的抑菌活性和较广的抑菌谱,对几种主要作物真菌和卵菌病害具有较好的田间防治效果,应用前景广。     

壳寡糖和钕复合处理诱导黄瓜对枯萎病的抗性

以"津研四号"黄瓜为试材,研究了壳寡糖和钕Nd3+对黄瓜幼苗的诱导抗病性及对枯萎病的防治效果。结果表明,50 mg/L壳寡糖和10 mg/L Nd3+复合处理的相对防效达74.7%,比50 mg/L壳寡糖和10 mg/L Nd3+的单独处理分别提高22.0%和43.8%。分析比较壳寡糖和Nd3+单独和复合处理黄瓜幼苗后,黄瓜根部防御反应相关酶系苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)、多酚氧化酶(PPO)、β-1,3-葡聚糖酶(GLU)比活性的变化趋势,发现壳寡糖和Nd3+复合处理黄瓜植株根部PAL、POD、PPO和GLU等防御酶活性呈上升趋势。研究表明,壳寡糖和Nd3+复合处理能诱导黄瓜幼苗对枯萎病的抗性,且诱导黄瓜抗病性的产生与激活黄瓜相关防御酶的活性有关。     

解淀粉芽胞杆菌YB114对黄瓜棒孢叶斑病的生防效果及发酵条件优化

解淀粉芽胞杆菌YB114为本研究团队筛选出的一株对黄瓜棒孢叶斑病(Corynespora leaf spot)具有较高活性的生防菌株。为加快其产业化进程，本试验研究了该菌株的生物活性及发酵条件。盆栽试验结果表明，100倍发酵稀释液处理对黄瓜棒孢叶斑病的治疗及预防效果分别为85.72%和42.29%,100倍发酵上清稀释液的治疗及预防效果分别达到74.14%和33.25%,菌株发酵液和上清液对黄瓜棒孢叶斑病的治疗效果好于预防效果。YB114发酵液对黄瓜植株有促生效果，叶面喷施后黄瓜茎长、根长、叶面积及地上部生物量增加，叶片中叶绿素、生长素和玉米核苷素含量显著增加。发酵最优培养基为10 g/L果糖、17 g/L水溶性花生饼粉、1 g/L磷酸二氢钾。最佳发酵条件为：装液量40 mL/250 mL三角瓶，接种量6%(体积分数)、pH 7.0,转速180 r/min,温度32℃,发酵时间24 h。优化发酵条件后YB114对棒孢叶斑病的防效提升了22.4%。     

强酸性电生功能水对番茄白粉病和细菌性叶斑病防治效果初探

为探索强酸性电生功能水对番茄白粉病和番茄细菌性叶斑病的防治效果,分别以1×10~6孢子/g寡雄腐霉菌可湿性粉剂和46%氢氧化铜水分散粒剂为对照药剂,采用不同浓度的强酸性电生功能水在番茄缓苗期和发病初期进行叶面喷施。结果表明,在缓苗后用50 mg/L强酸性电生功能水进行预防,在病害发生初期改用80 mg/L浓度进行防治,对番茄白粉病和番茄细菌性叶斑病均有较好的防治效果,防效分别为64.10%和66.14%,而且可使番茄增产2.80%;仅在病害发生初期开始使用80 mg/L强酸性电生功能水进行叶面喷施,对番茄有一定增产效果。但是,对番茄白粉病和番茄细菌性叶斑病的防治效果与对照差异不显著。     

N-(2-三氟甲基-4-氯苯基)-2-吡唑酰氨基环己烷基磺酰胺类化合物的合成与杀菌活性

吡唑酰胺类杀菌剂是近年新农药开发的热点。本研究采用EDCI/HOBt酰胺化法合成了14个结构新颖的N-(2-三氟甲基-4-氯苯基)-2-吡唑酰氨基环己烷基磺酰胺类化合物 ( 3a ~ 3n ),其结构均经1H NMR、13C NMR、质谱和元素分析确认,并用X-射线衍射法确定了化合物 3g 的单晶结构和立体构型。菌丝生长速率法试验结果表明,化合物 3a 、 3e 和 3j 对番茄灰霉病菌Botrytis cinerea KZ-9的EC₅₀值分别为4.28、10.08和11.31 mg/L,抑菌活性不及对照药剂啶酰菌胺和腐霉利;但在孢子萌发试验中,目标化合物表现出与对照药剂相近的抑菌活性,在10 mg/L下有7个化合物对灰霉病菌孢子萌发的抑制率超过了85%;在番茄活体盆栽试验中,化合物 3e 在200 mg/L下对番茄叶片及其花上灰霉病菌的防治效果分别为77.5%和65.2%,高于对照药剂啶酰菌胺 (防效分别为59.8%和30.3%),有进一步研究的价值。     

5种药剂防治黄瓜细菌性角斑病药效试验

<正>黄瓜细菌性角斑病是红花岗区黄瓜生产上的第一大病害,常年中等程度发生,部分田块偏重发生,严重影响黄瓜的产量和经济效益。农户乱用药现象普遍,防治效果差,不能有效控制黄瓜细菌性角斑病的发生为害。为此,我们于2014年9月6—19日,选用5种低毒杀菌剂对黄瓜细菌性角斑病进行防治试验,以筛选出防治黄瓜细菌性角斑病效果好的低毒对路杀菌剂进行推广应用。1材料与方法1.1供试药剂     

土壤环境条件对威百亩熏蒸防治黄瓜枯萎病的影响

为探究威百亩在不同土壤环境条件下的消毒效果,采用离体和活体方法研究施药量、覆膜熏蒸时间、土壤相对含水量及土壤温度对威百亩熏蒸防治黄瓜枯萎病的作用效果。结果表明,25℃条件下,威百亩12 mg(a.i.)/kg土壤熏蒸消毒,对尖孢镰刀菌Fusarium oxysporum的抑制率为78.82%,对黄瓜枯萎病的防治效果为87.03%,且对作物安全无药害;威百亩对尖孢镰刀菌的熏蒸抑制作用随着熏蒸时间的增加而增强,土壤熏蒸10 d后对尖孢镰刀菌的抑制率为95.21%;土壤相对含水量为30%和50%时,威百亩对黄瓜枯萎病的防治效果分别为72.32%和82.14%,含水量过高或过低均不利于药效的发挥,而且还会对作物产生药害反应。威百亩的熏蒸效果随着土壤温度的升高而增强,在25、30、35℃时对黄瓜枯萎病的防治效果分别为80.18%、98.20%和100.00%。表明威百亩结合日光消毒温度大于25℃、土壤相对含水量为30%或50%、熏蒸10~15 d可有效控制土壤中尖孢镰刀菌引起的黄瓜枯萎病。     

黄瓜枯萎病拮抗菌的拮抗促生因子检测及生物效应研究

以黄瓜枯萎病病原菌,尖孢镰刀菌黄瓜专化型(FOC,Fusarium oxysporum f.sp.cucumerinum)为靶标筛选拮抗菌。通过初筛和复筛,获得2株对尖孢镰刀菌黄瓜专化型拮抗效果稳定、拮抗能力较强的细菌QHZ-Yb1和QHZ-Yb2(以下简称,Yb1和Yb2),采用平板对峙法测定其拮抗作用,抑菌带宽度达3.37 mm和3.42 mm,抑菌圈直径2.7 cm,抑菌率分别达到61.9%和62.3%;通过形态学结合生理生化及菌株的16S rDNA序列分析,初步确定这两株菌均为萎缩芽孢杆菌(Bacillus atrophaeus);潜在拮抗促生因子的测定结果表明:菌株Yb1和Yb2具有多种拮抗促生因子,其脂肽类粗提取物的抑菌率分别达到57.4%和58.0%,生长素IAA的分泌量可达1.56 mg·L~(-1)和3.69 mg·L~(-1),溶P量为0.77 mg·L~(-1)和1.19 mg·L~(-1),两个菌株均可产嗜铁素、分泌酪蛋白酶;种子萌发试验结果表明:Yb1和Yb2菌液均可促进黄瓜种子的萌发;菌株生物效应的盆栽试验结果表明:Yb1、Yb2以及Yb1+Yb2菌悬液的处理不仅对黄瓜枯萎病有明显的生防效果,而且可显著增加黄瓜植株的生物量,增加黄瓜植株根际土中细菌和放线菌的数量,减少真菌和尖孢镰刀菌的数量,尤其以Yb1+Yb2菌悬液的处理效果最显著,对黄瓜枯萎病的发病率降低11.11个百分点,植株生物量增加56.7%。结论:菌株Yb1和Yb2具有生防潜力,两菌株配合运用效果更好。     

Induction of Systemic Resistance in Cucumber against Several Diseases by Plant Growth-promoting Fungi: lignification and Superoxide Generation

Five fungal isolates (Trichoderma, Fusarium, Penicillium, Phoma and a sterile fungus) from zoysiagrass rhizosphere that promote plant growth were tested for their ability to induce systemic resistance in cucumber plants against Colletotrichum orbiculare. Roots of cucumber plants were treated with these fungal isolates using barley grain inocula (BGI), mycelial inocula (MI) or culture filtrate (CF). Most isolate/inoculum form combinations significantly reduced the disease except BGI of Trichoderma. These fungal isolates were also evaluated for induction of systemic resistance against bacterial angular leaf spot and Fusarium wilt by treatment with BGI. Penicillium, Phoma and the sterile fungus significantly reduced the disease incidence of bacterial angular leaf spot. Phoma and sterile fungus protected plants significantly against Fusarium wilt. Roots treated with CFs of these fungal isolates induced lignification at Colletotrichum penetration points indicating the presence of an elicitor in the CFs. The elicitor activity of CFs was evaluated by the chemiluminescence assay using tobacco callus and cucumber fruit disks. The CFs of all isolates elicited conspicuous superoxide generation. The chemiluminescence activity of the CF of Penicillium was extremely high, and its intensity was almost 100-fold higher than that of other isolates. The chemiluminescence activity was not lost following treatment with protease or autoclaving or after removal of lipid. The MW 12,000 dialyzed CF fraction was highly effective in eliciting chemiluminescence activity. Chemiluminescence emission from cucumber fruit disks treated with Penicillium was the same as that obtained from tobacco callus, except that the lipid fraction also showed a high activity. Both the MW 12,000 fraction and the lipid fraction induced lignification in the epidermal tissues of cucumber hypocotyls.     

Application of Rhizobacteria for Induced Resistance

This article provides a review of experiments conducted over a six-year period to develop a biological control system for insect-transmitted diseases in vegetables based on induced systemic resistance (ISR) mediated by plant growth-promoting rhizobacteria (PGPR). Initial experiments investigated the factors involved in treatment with PGPR led to ISR to bacterial wilt disease in cucumber caused by Erwinia tracheiphila. Results demonstrated that PGPR-ISR against bacterial wilt and feeding by the cucumber beetle vectors of E. trachiphiela were associated with reduced concentrations of cucurbitacin, a secondary plant metabolite and powerful beetle feeding stimulant. In other experiments, PGPR induced resistance against bacterial wilt in the absence of the beetle vectors, suggesting that PGPR-ISR protects cucumber against bacterial wilt not only by reducing beetle feeding and transmission of the pathogen, but also through the induction of other plant defense mechanisms after the pathogen has been introduced into the plant. Additional greenhouse and field experiments are described in which PGPR strains were selected for ISR against cucumber mosaic virus (CMV) and tomato mottle virus (ToMoV). Although results varied from year to year, field-grown tomatoes treated with PGPR demonstrated a reduction in the development of disease symptoms, and often a reduction in the incidence of viral infection and an increase in tomato yield. Recent efforts on commercial development of PGPR are described in which biological preparations containing industrial formulated spores of PGPR plus chitosan were formulated and evaluated for use in a transplant soil mix system for developing plants that can withstand disease attack after transplanting in the field.     

黄瓜土传病害拮抗细菌的筛选、鉴定及生防特性研究

为了有效防治黄瓜的土传病害,本文从黄瓜根际土壤中分离得到256株细菌,利用平板对峙试验筛选到一株拮抗菌ZM-1。通过形态、生理生化和分子生物学方法对菌株进行鉴定,测定菌株产生的抑菌物质。通过正交实验法与单因素法对菌株进行发酵优化,并通过盆栽试验测定菌株防病能力。结果表明,菌株ZM-1为铜绿假单胞菌Pseudomonas aeruginosa,该菌对黄瓜枯萎病菌Fusarium oxysporum f. sp. cucumebrium 和黄瓜疫病菌Phytophthora drechsleri的抑制率分别为62.80%和65.58%。该菌株可以产生纤维素酶、铁载体等多种抑菌物质。经过最佳发酵优化,菌株发酵液菌含量可达到1×10¹⁰ cfu/mL以上。最适发酵培养基配方为蔗糖5 g/L、胰蛋白胨10 g/L、K₂HPO₄ 10 g/L,发酵条件温度25 ℃、pH 7.5、时间48 h、接种量2%。盆栽试验表明,菌株ZM-1对黄瓜枯萎病和黄瓜疫病的防效分别为53.97%和51.11%。本研究表明拮抗菌ZM-1在防治黄瓜土传病害方面具有开发应用的潜力。     

小麦雪霉叶枯病产量损失研究

人工接种试验结果表明，雪腐格氏霉引起小麦成株期叶枯、鞘枯和穗腐。鞘枯使小麦穗粒重减少０．８％～３２．９％，千粒重降低９．５％～１６．９％；穗腐使小麦穗粒重减少９．６％～３９．８％，千粒重降低７．８％～１７．９％；鞘枯－穗腐复合症状使穗粒重减少１０．２％～６５．２％，千粒重下降９．５％～１４．８％，叶斑－鞘枯－穗腐使粒重减少１１．７％～５１．５％，千粒重下降１２．１％～１８．３％。     

Evaluation of cucumber (<Emphasis Type="Italic">Cucumis sativus</Emphasis>) cultivars grown in Eastern Europe and progress in breeding for resistance to angular leaf spot (<Emphasis Type="Italic">Pseudomonas syringae</Emphasis> pv. <Emphasis Type="Italic">lachrymans</Emphasis>)

Increased occurrence of cucumber angular leaf spot, Pseudomonas syringae pv. lachrymans, has caused significant losses in cucumber, Cucumis sativus, yield in Poland in recent years. These losses necessitated evaluation of the level of resistance in cucumber cultivars of mainly Polish breeding, cultivated in Eastern Europe, and initiation of a breeding programme for resistance to this disease. Screening for resistance was performed on 84 cucumber accessions under growth chamber conditions using a highly aggressive strain of P. syringae pv. lachrymans. Most of the screened accessions were either susceptible or displayed intermediate resistance. The screening resulted in the identification of five F₁ hybrid cultivars moderately resistant to angular leaf spot. The identified F₁ hybrids were self-pollinated up to the F₄ generation. Individuals resistant to angular leaf spot were identified. These individuals can be used as a source of resistance to angular leaf spot in future breeding efforts.     

解淀粉芽胞杆菌YU-1对水稻纹枯病的防治作用

本文旨在筛选对水稻纹枯病有生防作用的菌株,并初步探索其生防作用机理。收集水稻、甘蓝、黄瓜等不同植物根际土壤,采用稀释分离和对峙培养法筛选对水稻纹枯病菌Rhizoctonia solani Kühn有抑菌作用的菌株;通过离体接种防效、盆栽防效、抑菌谱、对水稻纹枯病菌菌核萌发及形成的抑制作用等方面评价其生防潜力,并对生防菌株进行鉴定。结果表明,从采集的37份根际土壤中共分离获得细菌297株,其中4株对纹枯病菌具有较好的拮抗作用,菌株YU-1对水稻纹枯病菌菌丝生长的抑制率达89.8%;对西瓜枯萎病菌、草莓灰霉病菌、番茄早疫病菌、油菜菌核病菌、小麦赤霉病菌菌丝生长的抑制率均在85%以上;对水稻纹枯病的离体和盆栽防效分别为73.1%和66.3%;对水稻纹枯病菌菌核萌发的抑菌率在92%以上;经生理生化和分子鉴定为解淀粉芽胞杆菌Bacillus amyloliquefaciens。由此可看出,菌株YU-1对水稻纹枯病的防治具有较强的应用价值,具有进一步开发成生物农药的潜力。     

木霉分生孢子和厚垣孢子对黄瓜幼苗生理特性及枯萎病防效的影响

采用前期筛选出的对黄瓜枯萎病菌有较好拮抗作用的3株木霉菌,即哈茨木霉Trichoderma harzianum 809、拟康氏木霉Trichoderma pseudokoningii 886和棘孢木霉Trichoderma asperellum 525,利用盆栽试验,测定了木霉菌孢子不同类型施用对黄瓜幼苗生长、生理特性及枯萎病防效的影响。结果表明:哈茨木霉809、拟康氏木霉886、棘孢木霉525分生孢子和厚垣孢子对黄瓜枯萎病的盆栽防效均在66.81%以上,且以拟康氏木霉886厚垣孢子防效最高,达到81.46%。当黄瓜幼苗长至三叶一心时,3株木霉菌分生孢子和厚垣孢子处理的黄瓜幼苗株高、茎粗、根体积、叶面积、全株鲜质量均比CK显著上升,以厚垣孢子886的促进效果最显著,其株高、茎粗、根体积、叶面积、全株鲜质量分别较CK增加了85.33%、108.43%、235.29%、144.38%、272.32%。同时,3株木霉菌分生孢子和厚垣孢子处理的黄瓜幼苗叶绿素含量、根系活力、叶片可溶性糖含量、叶片可溶性蛋白含量也均比CK显著上升,厚垣孢子886的促进效果仍最显著,其叶绿素含量、根系活力、叶片可溶性糖含量、叶片可溶性蛋白含量分别较CK增加了97.47%、86.05%、172.49%、201.91%。     

Mixtures of plant growth-promoting rhizobacteria enhance biological control of multiple cucumber pathogens

ABSTRACT Plant growth-promoting rhizobacteria (PGPR) strains INR7 (Bacillus pumilus), GB03 (Bacillus subtilis), and ME1 (Curtobacterium flaccumfaciens) were tested singly and in combinations for biological control against multiple cucumber pathogens. Investigations under greenhouse conditions were conducted with three cucumber pathogens-Colletotrichum orbiculare (causing anthracnose), Pseudomonas syringae pv. lachrymans (causing angular leaf spot), and Erwinia tracheiphila(causing cucurbit wilt disease)-inoculated singly and in all possible combinations. There was a general trend across all experiments toward greater suppression and enhanced consistency against multiple cucumber pathogens using strain mixtures. The same three PGPR strains were evaluated as seed treatments in two field trials over two seasons, and two strains, IN26 (Burkholderia gladioli) and INR7 also were tested as foliar sprays in one of the trials. In the field trials, the efficacy of induced systemic resistance activity was determined against introduced cucumber pathogens naturally spread within plots through placement of infected plants into the field to provide the pathogen inoculum. PGPR-mediated disease suppression was observed against angular leaf spot in 1996 and against a mixed infection of angular leaf spot and anthracnose in 1997. The three-way mixture of PGPR strains (INR7 plus ME1 plus GB03) as a seed treatment showed intensive plant growth promotion and disease reduction to a level statistically equivalent to the synthetic elicitor Actigard applied as a spray.     

VA菌根对茄子、黄瓜的促生和防病效应

作者在盆栽条件下研究了Glomus versiforme、G.mosseae、G.macrocarpum和单孢分离的3株VA菌根土著菌对茄子、黄瓜的侵染、促生和防病作用。结果表明,供试菌均可侵染供试作物,但促生和防病效应具特异性。G.versiforme和G.mosseae均可促进茄子的生长,然而只前者减轻了黄萎病。G.spa使黄瓜提早开花,但不防病。G.macrocarpum减轻了细菌性角斑病的发生,但并无促生作用。s     

木霉分生孢子和厚垣孢子对黄瓜叶片抗氧化系统及枯萎病防效的影响

采用前期筛选出的对黄瓜枯萎病菌有较好拮抗作用的3株木霉菌,即哈茨木霉菌(Trichoderma harzianum)809、拟康氏木霉菌(Trichoderma pseudokoningii)886和棘孢木霉菌(Trichoderma asperellum)525,利用盆栽试验,测定了木霉菌分生孢子和厚垣孢子对黄瓜幼苗抗氧化能力及对枯萎病防效的影响。结果显示:3株木霉菌分生孢子和厚垣孢子对黄瓜枯萎病的盆栽防效均在66.81%以上,且以拟康氏木霉菌886厚垣孢子防效最高,达到81.46%;当黄瓜幼苗长至三叶一心时,与CK(即只接种病原菌)相比,经哈茨木霉菌809、拟康氏木霉菌886、棘孢木霉菌525分生孢子以及厚垣孢子处理后,黄瓜幼苗叶片相对电导率和丙二醛(MDA)含量均呈下降趋势,而保护性酶包括过氧化物酶(POD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)、超氧化物歧化酶(SOD)活性则呈上升趋势,其中以拟康氏木霉菌886厚垣孢子的变化幅度最显著;拟康氏木霉菌886厚垣孢子处理的黄瓜幼苗叶片相对电导率、MDA含量分别比CK下降了47.74%、41.40%;而叶片中的POD、CAT、APX、SOD活性则分别比CK增加了318.11%、155.36%、157.09%和300.34%。研究表明3株木霉菌分生孢子和厚垣孢子均能通过改善黄瓜幼苗叶片抗氧化能力,增加保护酶活性,提高了对黄瓜枯萎病的防治效果。