农作物菌类病害3区分

分清真菌病害、细菌病害和病毒病这三种病害,对于防治,特别是药剂防治来说是十分重要的。不同药剂防治不同病害,能杀真菌的药剂未必能防病毒,能治病毒的又管不了细菌。     

加瑞农防治蔬菜病害简报

蔬菜品种多,茬口复杂,种植方式多样,病害防治乃是蔬菜生产十分突出的问题。据调查,京郊蔬菜病害500余种,其中30余种主要病害需要防治。多年来,一些病害一直没有找到理想的对路药剂,80年代以来,多种进口和国产杀菌剂推广应用,对控制和减轻蔬菜病害发挥了积极作用,但细菌性病害和少数真菌病害防治问题仍未得到很好解决。同时,由于蔬菜施药水平高,长期单一使用的现象严重,病菌很快产生抗性,许多杀菌剂对     

《病害防治的新战略》出版发行

《病害防治的新战略》是由日本驹田旦、稻叶中兴等活跃在病害防治研究各领域第一线的一流学者共同完成的新著作,全书共318页,由日本全国农村教育协会负责发行。该书针对目前合成农药防治病害存在的弊端提出了防治新战略,搜集了最近信息,展示了防治研究现状。     

牡丹主要病害的识别

牡丹是我国传统名花,作为观赏栽培和药用已超过1500年的历史。牡丹病害有20种以上。防治牡丹病害应掌握不同病害识别特征、发生规律,采用综合药剂防治措施,以达到较好的防治效果。1牡丹病害特征的识别     

读者作者编者

我读了1986年第11期《植物防疫》上大畑贯一先生的“利用尖端技术防治病害的现状和问题”一文,很受启发。尖端技术开拓了病害防治的新领域,尤其是病毒病的防治。目前我国有关病害的防治农药还不多,防治病毒病根本就没有实用农药,主要防治方法是消灭媒介,但往往是病毒已经侵染才防治;抗病品种也很少。现在开始使用生物工程的基本技术,利用微生物诱导抗性,培     

噬菌体防治植物细菌性病害研究进展

植物病原细菌是限制农业生产的主要原因之一,作物受害严重,造成巨大的经济损失。化学防治、农艺防治以及抗病育种等方法,对植物细菌性病害实现了较好的防治,但是这些方法各自存在着不足之处。噬菌体无处不在,有细菌的地方就有噬菌体。噬菌体具有特异性,可以自我复制,相比于植物细菌性病害的其他防治方法,噬菌体防治环境友好,且制造成本低廉,越来越多的研究学者尝试用噬菌体控制细菌性病害,以补充传统防治方法的不足。本文列举了一些较为严重的植物细菌性病害的为害、传统的防治办法,并总结了已有的噬菌体防治手段以及噬菌体防治的发展前景。     

芹菜常见病害的田间诊断与防治措施

芹菜常见病害主要有晚疫病、早疫病、黑腐病、灰霉病、细菌性软腐病和病毒病等,对芹菜造成一定的为害。为了有效防治芹菜病害,笔者现介绍芹菜常见病害的防治方法。     

黔东南地区葡萄主要病害发生特点及防治技术

近年来,随着农业产业化结构的调整,黔东南州葡萄栽培面积逐年上升,但由于春夏季气温高,雨量大,有利于葡萄病害的发生,加上防治措施不力,延误最佳防治时期,葡萄病害特别严重,常造成低产、劣质葡萄,商品价质不高.据多年对州内葡萄病害的调查研究及防治实践,总结出黔东南州葡萄主要病害发生特点及防治技术,现将结果报告如下:     

烟叶主要病害识别诊断要点和综防技术

烟叶是渑池县主要经济作物,病害防治是烟叶生产上的一个关键环节。介绍烟草上主要病害的识别诊断要点,并提出防治策略。     

棚室蔬菜病害的关键防治技术

随着种植业结构的调整 ,大棚蔬菜面积不断扩大。由于大棚蔬菜的生态环境和栽培模式不同于露地蔬菜 ,大棚内蔬菜病害发生更为严重。要做好病害的防治工作 ,用准药、用好药、少用药 ,就要根据棚菜病害的发生特点 ,抓住以下几个防治环节 ,生产无公害蔬菜。1　识别病害类型准确用好药剂蔬菜病害可分为 2类 :一是由于不良的环境引起的病害称为非侵染性病害 ,也称生理病害 ,如低温冻害、高温灼伤等 ,发病往往是全棚或大面积的。生理病害发生一段时间后 ,有时转化成侵染性病害 ,防治这类病害的关键是找到原因 ,改善生长环境。二是由真菌、细菌、病…     

Reduced efficacy of fluazinam against <Emphasis FontCategory="SansSerif" Type="Italic">Phytophthora infestans</Emphasis> in the Netherlands

Phytophthora infestans is the causal organism of potato late blight, the most important disease in potato, the second most important arable crop in Europe. The P. infestans population in Europe is well known for its sudden changes in composition. Currently it is composed of a wide variety of genotypes, some of which are dominant clonal lines while others are rare or even unique to a year or location. Fungicides play a crucial role in the integrated control of late blight. Since its introduction in the Netherlands in 1992, fluazinam has been used in late blight control strategies in ware and starch potatoes. It has a broad spectrum of activity and is effective against a range of diseases including potato late blight. Fluazinam interrupts the pathogen cell’s energy production process by an uncoupling effect on oxidative phosphorylation. It is considered to have a low resistance risk. Until recently, reduced efficacy against fluazinam was not detected in P. infestans surveys in Europe. In this paper we present the finding of a new clonal lineage (EU_33_A2) of P. infestans in the Netherlands and the reduced efficacy of fluazinam to control one of the EU_33_A2 isolates in field experiments carried out in 2011 and 2015 under high disease pressure. The potential effects of this finding on practical late blight control strategies are discussed.     

农抗120防治花生叶斑病药效试验

在山东省经多点试验,用200倍农抗120防治花生叶斑病,防效达69.6～78.1％,比500倍多菌灵防效57.4～66.5％,高11.6～12.2％。并对花生有刺激生长的作用,喷施农抗120的主茎高26.2厘米,侧枝长31.4厘米,单株果重18.8克,比对照主茎高1.3厘米,侧枝长2.3厘米,单株果重增加2.7克,增产11.6～18.5％。     

Dehydro-alpha-lapachone isolated from Catalpa ovata stems: activity against plant pathogenic fungi

The methanol extract of stems of Catalpa ovata G Don exhibits potent in vivo antifungal activity against Magnaporthe grisea (Hebert) Barr (rice blast) on rice plants, Botrytis cinerea Pers ex Fr (tomato grey mould) and Phytophthora infestans (Mont) de Bary (tomato late blight) on tomato plants, Puccinia recondita Rob ex Desm (wheat leaf rust) on wheat plants and Blumeria graminis (DC) Speer f. sp. hordei Marchal (barley powdery mildew) on barley plants. An antifungal substance was isolated and identified as dehydro-alpha-lapachone from mass and nuclear magnetic resonance spectral data. It completely inhibited the mycelial growth of B. cinerea, Colletotrichum acutatum Simmonds, Colletotrichum gloeosporioides Simmonds, M. grisea and Pythium ultimum Trow over a range of 0.4-33.3 mg litre(-1). It also controlled the development of rice blast, tomato late blight, wheat leaf rust, barley powdery mildew and red pepper anthracnose (Colletotrichum coccodes (Wallr) S Hughes). The chemical was particularly effective in suppressing red pepper anthracnose by 95% at a concentration of 125 mg litre(-1).     

苯并-1,2,3-噻二唑羧酸酯的合成及生物活性

为了寻找更多具有高诱导抗病活性的新化合物,基于对植物抗病激活剂S-甲基苯并 噻二唑-7-羧酸酯(BTH)的结构修饰,设计合成了5个新的含有柔性链及卤原子的苯并噻二唑-7-羧酸酯衍生物,其结构均经过核磁共振氢谱、质谱或元素分析及红外光谱确证。生物活性筛选结果显示,在500 mg/L质量浓度下,化合物 5e及5c对供试的细菌性病害和真菌性病害具有较好的防治效果,其中5e 对瓜类白粉病、瓜类炭疽病和水稻白叶枯病的防治效果均高于90%。     

利用蜜蜂传播生防菌防治梨火疫病

梨火疫病由梨火疫病菌(Erwinia amylovora)引起,可以通过蜜蜂授粉传播而加重危害.为做好香梨安全授粉工作,防止因直接放蜂造成梨火疫病的大流行,本研究测试了香梨花上分离的一株解淀粉芽孢杆菌(Bacillus amyloliquefaciens)对梨火疫病菌的拮抗效果,并利用自行研发的"蜜蜂导向盒"进行了蜜蜂...     

普通小麦“兰考90(6)”品系对白粉病抗性的遗传研究

 普通小麦(Triticum aestivum L.)"兰考90(6)"系列品系是以六倍体小黑麦(X Triticosecale Wittmack;AABBRR)为白粉病抗源培育的新的小麦-黑麦1BL/1RS异易位系。这些品系高抗白粉病。小麦白粉病抗性基因推导试验证明,"豫麦66"携带的抗病基因与大多数已经报道的小麦抗白粉病基因不同。用白粉菌[Blumeria graminis (DC.) E. O. Speer f. sp. tritici]单孢堆分离物进行的遗传分析表明,"兰考90(6)"品系携带一个小种专化的隐性抗白粉病基因。对"中国春"和"兰考90(6)21-12"杂交F₂分离群体进行1RS染色体检测,结果证明该抗白粉病基因不在1RS染色体臂上。本研究为有效利用"兰考90(6)"系列品系中的抗白粉病基因提供了科学依据。     

中稻纹枯病为害损失的研究

作者研究了中稻纹枯病所致的产量损失,结果表明:瘪谷、不实率增多及实粒的千粒重下降是水稻纹枯病影响稻谷减收的主要因素,它们与病情的关系呈幂函数曲线。纹枯病的为害除影响稻谷减收外,还导致出米率下降和碎米率增高。纹枯病的为害以黄熟初期的病情指数与稻谷减收率的关系最密切,根据试验数据经多种曲线拟合,比较其拟合度,以韦布尔模型最优,其稻谷减收率的函数式为: Y=1-exp[-((X-0.03840)/(1.47235))~(1.7005)] 式中Y为稻谷减收率,X为黄熟期病情指数。     

农抗120防治小麦白粉病的应用技术研究

1989—1990年在河南省8个县市对农抗120防治小麦白粉病进行了田间试验。结果表明:在4月上中旬,小麦白粉病发生的病株率达15～20％,病叶率10％左右时,应用100ppm农抗120喷雾防治2次,防效达70～85％。防病效果与防治时间、喷药次数和发病程度关系密切。施药越晚,效果越差。农抗120的防治效果优于多菌灵等常用化学药剂,在发病初期喷药2次,防治效果与施用粉锈宁相近,可作为粉锈宁紧缺情况下的首选替补药物。但在病害大流行时施用,作用缓慢,效果较差。     

Isolation and antifungal activity of lignans from Myristica fragrans against various plant pathogenic fungi

BACKGROUND: In a search for plant extracts with potent in vivo antifungal activity against various plant diseases, we found that treatment with a methanol extract of Myristica fragrans Houttyn (nutmeg) seeds reduced the development of various plant diseases. The objectives of the present study were to isolate and determine antifungal substances from My. fragrans and to evaluate their antifungal activities. RESULTS: Three antifungal lignans were isolated from the methanol extract of My. fragrans seeds and identified as erythro-austrobailignan-6 (EA6), meso-dihydroguaiaretic acid (MDA) and nectandrin-B (NB). In vitro antimicrobial activity of the three lignans varied according to compound and target species. Alternaria alternata, Colletotrichum coccodes, C. gloeosporioides, Magnaporthe grisea, Agrobacterium tumefaciens, Acidovorax konjaci and Burkholderia glumae were relatively sensitive to the three lignans. In vivo, all three compounds effectively suppressed the development of rice blast and wheat leaf rust. In addition, EA6 and NB were highly active against the development of barley powdery mildew and tomato late blight, respectively. Both MDA and NB also moderately inhibited the development of rice sheath blight. CONCLUSION: This is the first study to demonstrate the in vitro and in vivo antifungal activities of the three lignans from My. fragrans against plant pathogenic fungi.     

Pathogenicity and toxigenicity of <Emphasis Type="Italic">Fusarium verticillioides</Emphasis> isolates collected from maize roots,stems and ears in South Africa

Sunflower (Helianthus annuus L.) is an important oilseed crop in South Africa, and is grown in rotation with maize in some parts of North West, Limpopo, Free State, Mpumalanga and Gauteng provinces. Alternaria leaf blight is currently one of the major potential disease threats of sunflower and is capable of causing yield losses in all production regions. Alternaria helianthi was reported as the main cause of Alternaria leaf blight of sunflower in South Africa; however small-spored Alternaria species have been consistently isolated from leaf blight symptoms during recent surveys. The aim of this study was to use morphological and molecular techniques to identify the causal agent(s) of Alternaria blight isolated from South African sunflower production areas. Alternaria helianthi was not recovered from any of the sunflower lesions or seeds, with only Alternaria alternata retrieved from the symptomatic tissue. Molecular identification based on a combined phylogenetic dataset using the partial internal transcribed spacer regions, RNA polymerase second largest subunit, glyceraldehyde-3-phosphate dehydrogenase, translation elongation factor and Alternaria allergen gene regions was done to support the morphological identification based on the three-dimensional sporulation patterns of Alternaria. Furthermore, this study aimed at evaluating the pathogenicity of the recovered Alternaria isolates and their potential as causal agents of Alternaria leaf blight of sunflower. Pathogenicity tests showed that all the Alternaria alternata isolates tested were capable of causing Alternaria leaf blight of sunflower as seen in the field. This is the first report of A. alternata causing leaf blight of sunflower in South Africa.