吉林省玉米主推品种抗丝黑穗病及叶斑病性状鉴定

对吉林省玉米主推品种进行了丝黑穗病及叶斑病的抗病性鉴定。结果表明：四单158、登海1、登海9、丹638、农大108、吉单209、吉单156、垦粘1、掖单19、吉单141、吉单306等较感染丝黑穗病。多数品种均不同程度感染灰斑病、弯孢菌叶斑病及褐斑病。对丝黑穗病及叶斑病抗性均较好的品种为“吉单180”。     

种衣剂防治玉米丝黑穗病药效试验

明确了不同成分种衣剂对玉米丝黑穗病的防治效果。试验表明,黑穗净防效最好84.88%,黑虫双全次之75.08%,吉农4号50.19%,其余几种种衣剂防效均低于50%。     

慈姑黑粉病病原菌名称的演变

慈姑黑粉病是慈姑生产中最重要的病害之一。病原菌最初被认为是慈姑实球黑粉菌。随着属名的变化,该病原菌被转移到虚球黑粉菌属称为慈姑虚球黑粉菌。最新研究表明,该病原菌与侵染可变慈姑的病原菌是同种,是畸形虚球黑粉菌的异名。本文说明了慈姑黑粉病病原菌名称演变原因以及最新进展,这对准确应用病原菌名称提供了参考依据。     

稻曲病菌菌核降解微生物的筛选与作用机制分析

菌核是稻曲病菌天然的越冬菌源和来年病害发生的重要初侵染源,控制田间菌核越冬数量能够从源头上遏制和减轻稻曲病的发生。为此,本研究对来自稻田土壤、菌核表面、以及青海高原的能够降解菌核的真菌进行了筛选,得到了6个有较好降解作用的生防菌株。在实验室条件下它们能够在30~70 d内彻底降解稻曲病菌菌核。真菌形态特征和rDNA-ITS序列分析表明,这些菌株分别为淡色生赤壳菌Bionectria ochroleuca、粘鞭霉Gliomastix polychroma、烟曲霉Aspergillus fumigatus、草酸青霉Penicillium oxalicum、粉红粘帚霉Gliocladium spp.和疣孢漆斑菌Myrothecium verrucaria。进一步超微结构观察发现,不同生防菌对菌核的降解机制可分为以重寄生作用和直接降解为主2种基本模式。春季田间撒施试验表明,其中2种生防菌的防治效果可达33.9%和46.8%。     

2种杀菌剂对籼粳交水稻品种‘甬优12’稻曲病防治效果及机理研究

为探明高效杀菌剂用药量和防治时期对水稻稻曲病的防治效果及防治机理,研究了2种杀菌剂的3个用药量和8个用药时期对籼粳交水稻品种‘甬优12’稻曲病的防效。结果表明,在推荐用量范围内对稻曲病防治效果较好,随着用量上升防效有提高趋势,但除喜奥300 g/hm~2用药量防效显著低于其他处理外,用药量不是影响防效的关键因素;2种杀菌剂在破口前20天就开始具有一定防效,越接近开花期,防效越明显,破口后防效开始呈下降趋势,其中喜奥在齐穗期后防效下降较为迅速。因此认为,稻曲病在侵染‘甬优12’的关键时期是在开花期,可选用长效高效杀菌剂,于破口前进行防治。     

Survey and examination of the potential alternative hosts of Villosiclava virens,the pathogen of rice false smut,in China

Rice false smut is caused by ascomycete Villosiclava virens, whose potential alternative hosts have been assumed previously. Here its potential alternative hosts were surveyed and identified from 2008 to 2013 in the main rice-growing regions in China. Two common weeds in paddy fields, Digitaria sanguinalis Scop. and Echinochloa crusgalli(L.) Beauv., were found to present the similar symptoms to smut diseases in a few individuals in 2012 and 2013 in Zhejiang and Sichuan provinces of China, respectively. After the examinations of the spore morphology, their infection and extension mode in hosts, pathogen cell wall components, and molecular identification, the two pathogens were identified to be the Basidiomycetes, Ustilago syntherismae and Ustilago trichophora, respectively. So far there has been no alternative host of V. virens to be identified in China. These suggest that the alternative hosts of V. virens, if they do exist, are not possible to play an important role in the pathogen life cycle and the disease epidemics.     

Epiphytic colonization of Ustilaginoidea virens on biotic and abiotic surfaces implies the widespread presence of primary inoculum for rice false smut disease

Ustilaginoidea virens (Uv), the causative agent of rice false smut disease, infects developing rice spikelets at the booting stage, and transforms individual grains of the panicle into smut balls. Epidemics of the disease occur when the rice booting and heading stages coincide with rainy days. Using a green fluorescent protein (GFP)‐labelled Uv isolate that can form false smut balls on rice panicles, it was found that under high humidity and free water conditions the Uv isolate could colonize leaves of plants belonging to various families including the Poaceae (Oryza sativa, Echinochloa crusgalli, Digitaria sanguinalis and Leptochloa chinensis), the Brassicaceae (Arabidopsis thaliana) and the Solanaceae (Nicotiana benthamiana) without symptoms. Over several days, some conidia could germinate on the leaves of these plants and in water on the surface of Parafilm and cellophane, form hyphae and differentiate conidiophores to generate a large number of secondary conidia, while other conidia were able to directly produce secondary conidia. Conversely, in the absence of water some conidia could either bud to form new conidia or were converted into chlamydospores. These data indicate that Uv is one of a few fungal pathogens reported to have epiphytic characteristics. The rapid generation of a large number of spores on biotic and abiotic surfaces greatly increases the inoculum that can infect rice spikelets, resulting in the occurrence of rice false smut disease epidemics. These findings are important in the development of disease control strategies.     

水稻粒黑粉病研究进展

稻粒黑粉病已经成为杂交稻制种田的重要病害。目前国际上关于稻粒黑粉病的研究总体看来还较少,也存在较多的争议。主要回顾和总结了国内外对水稻粒黑粉病的研究情况,对发病症状、病原物及其分类地位、生物学特性、病害循环与侵染机制、发病因素与病害流行、分级标准和综合防治进行了综述,同时探讨了目前关于该病害研究所存在的争议及以后值得研究的方向。     

不同温热比例的半外来群体选系的丝黑穗病抗性鉴定

根据玉米幼苗可溶性总糖含量的多少及其与田间发病率的相互转化关系来判断半外来群体选系丝黑穗病的抗性,用此方法对174份半外来群体选系的丝黑穗病抗性进行了鉴定.结果表明:在供试的玉米半外来群体选系中,感病材料比例>50%的有B73×Pob45和丹340×Pob70 2个群体;Mo17×Pob46群体中,中抗材料和感病材料所...     

玉米自交系昌7-2对丝黑穗病抗性改良的初步研究

将旅大红骨种质导入黄改代表系昌7-2中,研究其对昌7-2玉米丝黑穗病抗性的改良效果。结果表明,旅大红骨种质总体上有利于提高玉米自交系昌7-2对丝黑穗病的抗性,可作为对昌7-2丝黑穗病抗性改良的可用抗源。其中玉米自交系丹598、辽1213对其改良的效果更为明显。