生物农药对河西灌区枸杞白粉病防治效果研究

通过对枸杞(Lycium chinense)病害大量的调查研究,针对枸杞白粉病,采用生物源农药50%醚菌酯、乙蒜素、46%咪鲜·几丁糖、3%克菌康可湿性粉剂进行防治。结果表明:对枸杞白粉病防治效果、单株产量和果粒大小防治效果最好的是1 500mg/L 50%醚菌酯,依次是3%克菌康可湿性粉剂、咪鲜·几丁糖、乙蒜素。     

马占相思白粉病的发生及化学防治

以不同药剂、不同浓度、不同处理方法对马占相思白粉病进行野外防治试验,并对结果作方差分析,结果表明:甲基托布津70%可湿性粉剂的1 000~2 000倍液对马占相思白粉病有良好的防治效果,相对防效达90%以上;马占相思白粉病野外化学防治以甲基托布津70%可湿性粉剂1 000倍液 粉锈宁15%可湿性粉剂1 000倍液 腈菌唑12.5%可湿性粉剂3 000倍液常规喷雾防治为佳。     

5种杀菌剂对香樟炭疽病菌的室内药效试验

利用50%多菌灵可湿性粉剂、156g/L丙环唑乳油、50%嘧菌酯水分散粒剂、12%咯菌腈悬浮剂和竹醋原液,采用生长速率法对香樟炭疽病病原菌进行了室内药效试验,测定了几种杀菌剂的抑菌率和室内毒力,以为田间防治提供依据。结果表明:50%多菌灵可湿性粉剂对香樟炭疽菌的防效最好,其次为156g/L丙环唑乳油和12%咯菌腈悬浮剂,50%嘧菌酯水分散粒剂和竹醋液对香樟炭疽病菌的防效较差。     

猕猴桃果实腐烂病田间药效试验

用不同浓度的70%甲基硫菌灵可湿性粉剂、50%咪鲜胺锰盐可湿性粉剂、75%肟菌·戊唑醇水分散剂、5%己唑醇微乳剂、10%苯醚甲环唑水分散粒剂及施药时间、不同施药次数对猕猴桃腐烂病进行田间药效防治试验。结果表明:己唑醇1 000倍、1 500倍和2 000倍3个处理防治效果分别为81.1%、59.2%和42.5%;用己唑醇1 500倍的施药时间和次数试验结果表明,谢花后一周内施药的处理防治效果均在60%左右,显著高于延后一周施药的处理,施药次数对防治效果影响不大,喷药3次和4次的防治效果均为59%左右,喷药2次防效较差,但与前两者差异不显著;5种杀菌剂药效试验结果表明,75%肟菌·戊唑醇水分散剂防效最好,为71%,显著高于其他处理,其次为咪鲜胺锰盐、己唑醇,防治效果分别为63.5%和52.4%,苯谜甲环唑和甲基硫菌灵防效较差均不足30%。     

6种杀菌剂对苹果炭疽病的防治效果

采用6种杀菌剂进行了防治苹果炭疽病的田间试验,结果表明:在发病前施药防治苹果炭疽病,试验中6种杀菌剂均具有一定的防效,在处理剂量范围内对果树安全。第5次药后第2次调查:40%福·福锌可湿性粉剂1333、1600(mg/kg)效果最好,防效分别为90.32%和92.51%,其次为40%苯醚·甲硫可湿性粉剂444、667(mg/kg);30%戊唑·咪鲜胺可湿性粉剂200、300(mg/kg);;60%唑醚·代森联水分散粒剂400、600(mg/kg),防治效果均在85%以上。生产上应在发病前施药,间隔14d喷药1次,连喷5次.     

3种药剂对刺梨白粉病的药效研究

为了研究25%乙嘧酚磺酸酯对刺梨(Rosa roxbunghii)白粉病的防治效果,本文采用乙嘧酚磺酸酯对刺梨白粉病进行田间防治试验。计算田间病情指数,确定田间防效,分析乙嘧酚磺酸酯对刺梨白粉病防治的有效性。结果表明,25%乙嘧酚磺酸酯微乳剂(250mg/L),对刺梨白粉病田间防治效果最好,在第7、14天田间防治效果分别为86.29%、95.08%,药后14d防治效果与10%苯醚菌酯和25%腈菌唑推荐使用剂量的效果相当,都在95%左右。结果表明,乙嘧酚磺酸酯是防控刺梨白粉病的有效药剂,在发病初期开始喷药,间隔7d喷第2次,可有效控制白粉病的发生危害。     

3种杀菌剂对葡萄霜霉病的田间防治试验

本文就3种杀菌剂对葡萄霜霉病的田间防治效果进行了评价。70%丙森锌可湿性粉剂和72%锰锌·霜脉可湿性粉剂对葡萄霜霉病均有很好的防治效果。70%丙森锌可湿性粉剂400～600倍液,在第2次药后7d防效均在79%以上,第3次药后14d防效均在81%以上。72锰锌·霜服可湿性粉剂600～800倍液,在第2次药后7d防效均在65肠以上,第3次药后14d防效均在76%以上。35氢氧化铜氯化钙重盐可湿性粉剂防治效果不理想,施药3次后的防效达59%以上.     

多粘类芽孢杆菌对木麻黄青枯病的抑菌防病作用

室内测定了商品化生物农药多粘类芽孢杆菌可湿性粉剂对木麻黄青枯病病原菌的毒力。采用打孔法结果表明,多粘类芽孢杆菌对木麻黄青枯病病原菌具有良好的拮抗作用,其抑菌圈的平均直径达到9.4 mm。采集4个品系的木麻黄小枝水培生根后进行温室盆栽,采用改进的伤根淋菌法进行接种,以只施多粘类芽孢杆菌可湿性粉剂(CK1)和只接种青枯菌(CK2)为对照,施用多粘类芽孢杆菌可湿性粉剂后接种青枯菌为处理进行实验。结果表明,在两个时间点,湛江-3的防效达到了60.8%和51.6%;湛江-2的防效达到了41.5%和40.3%;广东A14的防效达到了28.8%和23.3%,差异均显著(α=0.05);广东701-3的防效为16.3%和26.8%,差异不显著,出现此原因是广东701-3抗性强于其他3个品系。综上所述,在盆栽试验中,多粘类芽孢杆菌可湿性粉剂对木麻黄青枯病有显著的防治效果,品系本身越感病,防效越高。     

3种药剂防治雪松长足大蚜药效试验

选用不同浓度、不同处理的10%吡虫啉可湿性粉剂、4.5%高效氯氰菊酯微乳剂、45%毒死蜱乳油对雪松长足大蚜进行药剂喷洒试验。试验结果表明:喷药10d后,10%吡虫啉可湿性粉剂1500倍液和45%毒死蜱乳油1500倍液混合液加入经温水完全溶解的2‰洗衣粉、10%吡虫啉可湿性粉剂1500倍液和4.5%高效氯氰菊酯微乳剂2000倍液混合液加入经温水完全溶解的2‰洗衣粉这两个农药配方的防效达96%以上,是高效、生态、经济的防治雪松长足大蚜的方法。     

10种杀菌剂防治骏枣褐斑病田间试验

为筛选防治骏枣褐斑病的有效药剂,选用10种杀菌剂进行田间防治试验。结果表明:5%吡唑醚菌酯.55%代森联、10%苯醚甲环唑和48%波尔多液.30%代森锰锌有明显防治效果,考虑防效和使用成本,5%吡唑醚菌酯.55%代森联是比较经济适用的。田间试验表明混配成分杀菌剂可以避免红枣褐斑病病原菌的耐药性,建议作为常备杀菌剂使用;干旱情况下要适度增加喷药次数以提高药效。     

不同药剂对麻疯树白粉病的防治效果研究

选用日曹-甲基托布津70％可湿性粉剂、百菌清50％悬浮剂、云大翠丽5％己唑醇微乳剂和粉锈宁15％可湿性粉剂等4种高效低毒的农药对麻疯树白粉病进行大田药效试验,结果表明：4种药剂对麻疯树白粉病均具有显著的防治效果,其中以日曹-甲基托布津70％可湿性粉剂稀释800倍液的防治效果最好,3次施药后防治效果达88．89％,对麻疯树白粉病的防治效果显著且稳定,优于其他药剂;喷洒次数的增加可明显提高低浓度杀菌剂的防治效果,因此生产上应尽量使用低浓度药剂连续喷洒2～3次,可延缓麻疯树白粉病抗药性的产生。     

河口地区橡胶白粉病防治技术研究

研究认为河口地区～年橡胶白粉病防治失败的一个重要原因,是由于多年单一使用粉锈宁使19982000病原菌产生抗药性。采用以硫磺粉为主防药物,以古铜叶病率～作首次施药指标,叶片老化、病10%20%50%率达时进行一次全面喷防的防治技术,取得良好效果。40%     

大花月季白粉病发生情况研究

为给大花月季白粉病的预防提供理论依据,选取河南省南阳市常见的7个大花月季品种作为试验材料,对这7个大花月季品种白粉病的发生情况进行了调查,并对其抗性进行了对比分析结果发现:‘摩纳哥公主’属白粉病高抗品种,‘亚历克红’和‘希望’均属白粉病中抗品种,‘金凤凰’与‘香欢喜’均属白粉病感病品种,‘梅郎口红’与‘查克红’属白粉病严重感病品种;月季白粉病受温湿度的影响极为明显,5月为白粉病发病初期,6—8月气温较高,白粉病发病率较低,9—10月气温降低、温差增大,是月季生长的最佳时期,但此时也最容易发生白粉病,11月发病率明显下降。     

Coffee‐leaf extract and phosphites on the curative control of powdery mildew in eucalyptus mini‐stumps

The aim of this study was to evaluate the effectiveness of a plant extract obtained from the leaves of coffee plants infected by Hemileia vastatrix (NEFID), different formulations of phosphites and the combination of the extract and phosphites in controlling powdery mildew in eucalyptus mini‐stumps, as well as to study the effects on the production of mini‐cuttings and their rooting percentage. The experiments were conducted on two eucalyptus hybrids (‘urocam’ and ‘urograndis’) in a clonal garden and greenhouse. First, the NEFID plant extract and phosphites of copper, zinc, potassium and potassium/manganese were evaluated to determine their effectiveness in controlling powdery mildew and their toxic effect on the fungus' morphology. Subsequently, we analysed the direct fungitoxicity, curative efficiency and anti‐sporulating action of the NEFID extract and various combinations of phosphites with or without the extract, and we also evaluated their effects on shoot production and rooting in eucalyptus mini‐cuttings. The NEFID plant extract and phosphites of Cu, Zn and K/Mn were more effective than the fungicide pyraclostrobin + epoxiconazole in the control of powdery mildew. Potassium phosphite was not effective in controlling the pathogen. Among the tested mixtures, the combination of 50% NEFID plant extract and 50% copper phosphite was the most effective because it exhibited direct toxicity on powdery mildew, a high curative efficiency, anti‐sporulating action and no adverse effects on the production of shoots or rooting in eucalyptus mini‐cuttings.     

Identification,pathogenicity and control of powdery mildew caused by Erysiphe elevata on Eucalyptus pellita in Sumatra,Indonesia

Powdery mildews are biotrophic ascomycetes that do not typically kill their hosts, but instead interfere with normal plant growth. In Indonesia, white powdery spots were observed forming on the upper part of fully developed leaves of Eucalyptus pellita planted in sand beds of a clonal nursery. Thus, this study aimed to identify the causal agent of eucalypt powdery mildew in Indonesia as well as to develop control strategies to better manage the disease. Pathogen identification was based on morphology, molecular characterization of DNA sequencing the ITS region and pathogenicity test. In addition, considering that some powdery mildews are inhibited by free moisture on leaves, efficacy of foliar watering was tested for disease control. Phylogenetic analyses showed that isolates collected from infected eucalypt plants grouped together with other sequences of the Erysiphe elevata clade with bootstrap support of 99%; a similar result was also confirmed by morphological observations. Pathogenicity of powdery mildew on eucalypt plants was confirmed through artificial inoculation, thus fulfilling the Koch's postulates. For disease control, foliar watering reduced the incidence of powdery mildew on mother plants. The reduction of the disease incidence began to be more evident at 2 weeks after trial establishment, and in the fourth week, the incidence was below 10% in all three treatments, while the control was above 20%. Therefore, we concluded that E. elevata is the causal agent of powdery mildew in Indonesia and that one application of foliar watering per week was enough to minimize the disease impact in the nursery.     

Relationships between Oak powdery mildew incidence and severity and commensal fungi

Oak (Quercus robur) powdery mildew is a common and damaging fungal disease. In a local survey at Reading, UK, oak powdery mildew was common on trees of all height classes but was most common on trees of 3–9 m. A variety of other fungal species were commonly found growing in association with oak powdery mildew colonies. The abundance of such fungi was estimated through stratified sample surveys for 2.5 years. The taxa most commonly associated with oak powdery mildew were Acremonium sp., Trichoderma sp., Ampelomyces/Phoma sp. and Leptosphaerulina australis. Nearly 90% of mildew colonies were associated with L. australis, which is not generally considered as a mycoparasite or antagonist, in contrast with the other three fungi. Abundance varied between June and October surveys. Acremonium sp. abundance was greater in summer samplings, whereas L. australis and Trichoderma sp. abundances were greater in autumn samplings. Ampelomyces/Phoma sp. was never observed in the absence of powdery mildew. Relationships between the mildew‐associated fungi and oak powdery mildew appeared curved and differed significantly between sampling years. L. australis was positively correlated with the other three associated fungi studied when powdery mildew was also present . The variety and high population densities of the mildew‐associated fungi suggest that they may be important in determining the final density of oak mildew and the damage caused by it.     

Powdery mildew disease of rubber tree

Powdery mildew disease of rubber trees affects young rubber leaves, buds, inflorescences and other immature tissues reducing rubber latex yields by up to 45%. The disease is present in all rubber‐growing regions, with a high incidence rate in subtropical environments. The causal agent of powdery mildew disease of rubber trees was first described as Oidium heveae, but later research on the morphological characteristics suggests that O. heveae was in the past confused with Erysiphe quercicola. However, the most appropriate classification is still under debate between the genera Golovinomyces or Podosphaera. Molecular and phylogenetic analyses have established some relationships between rubber powdery mildew fungus and other powdery mildew species, but the generic sexual state of rubber powdery mildew fungus has not yet been established. Rubber powdery mildew conidia are wind‐spread spores that are produced in great numbers when growth conditions of the disease are favourable. The optimum conditions for conidial germination are 97–100% relative humidity and temperatures between 25 and 28°C. While some newly bred rubber clones have shown resistance to the disease, it can also be controlled with a number of fungicides and biological control agents. It is clear from recent knowledge about climate–fungus relationships that changes in weather strongly influence disease incidence and severity. The aim of this review is to highlight the classification conflicts, main causes and influencing factors behind the disease spreading, as well as draw attention to the impact of weather changes on the outbreaks of the disease. The information in this review will be helpful to adopt better control measures of the powdery mildew disease of rubber, especially in higher humidity areas, thereby minimizing the loss of rubber yields due to this disease.     

植物对白粉菌的亲和性研究进展

植物对白粉菌的亲和性是当前植物病理学研究的热点与难点之一。该研究在理论上为进一步了解活体寄生菌抑制植物防卫反应和利用植物活体营养的分子机制奠定了基础,在生产实践上,对于通过诱导植物对白粉菌感病基因发生突变或使基因沉默来培育植物抗白粉病新品种有重要意义。本文就细胞、生化以及分子水平上简要阐述了该方面的研究进展。     

石羊河下游干旱荒漠区梭梭人工林病害发生种类及防治对策

通过对石羊河下游干旱荒漠区梭梭人工林病害的调查,结果表明:梭梭人工林发生的各类病害有7种,其中:叶部病害有白粉病和枯萎病2种,枝干病害有枝枯病、瘤锈病、黑枯病和干桔病等4种,根部病害有根腐病1种.危害梭梭人工林主要病害有白粉病和枝枯病,有针对性地提出了防治对策.