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1.
The progress of development of stem-base pathogens in crops of second winter wheat was plotted in nine experiments in three years. The amount of each pathogen present was determined by quantitative PCR. Where Tapesia yallundae was present in quantifiable amounts, it usually developed earlier than the other eyespot pathogen, T. acuformis. Both species were usually present in greater amounts on cultivars which are more susceptible to eyespot. The sharp eyespot pathogen, Rhizoctonia cerealis, developed more erratically than either of the Tapesia spp. and there were no consistent effects on different cultivars. Fusarium spp., the cause of brown foot rot, were rarely present in quantifiable amounts, but Microdochium nivale was usually present as one or both of the varieties nivale and majus. Late-season (after anthesis) decreases in M. nivale suggest that any brown foot rot symptoms attributable to this fungus would have fully developed earlier. Cultivar differences in amounts of M. nivale were most clear in stems during internode extension and when relatively large amounts of DNA were present. Such differences approximately reflected eyespot susceptibility, cv. Soissons containing most and cv. Lynx containing least DNA. The results emphasise the difficulty in relating diagnoses, by quantitative PCR or other means, at early growth stages when decisions to apply fungicides against stem-base disease are made, to later disease severity.  相似文献   
2.
小麦品种纹枯病抗性鉴定   总被引:10,自引:0,他引:10  
小麦纹枯病是由禾谷丝核菌 (Rhizoctoniacere alis)侵染所致的土传病害[1 ] 。近年来 ,该病害在湖北省麦区发生日趋严重[2 ,3] ,已逐渐成为生产上的一种重要病害。培育抗纹枯病品种和鉴定筛选抗源并在育种工作中加以利用是控制该病害的重要途径。本研究对湖北省麦区近年来推广的 2 5个品种以及从全国各地征搜集的 548份材料进行了鉴定和筛选 ,以期明确湖北省麦区品种的抗性现状 ,为育种单位提供抗源和小麦品种合理布局提供科学依据。1 材料与方法1 .1 材 料供试小麦品种为湖北省近年来推广品种 2 5个和从全国各地征搜…  相似文献   
3.
黄淮麦区57个小麦品种对3株小麦纹枯病菌的苗期抗性鉴定   总被引:1,自引:0,他引:1  
分别从兰考、夏邑和嵩县的小麦纹枯病罹病植株中分离鉴定出3株小麦纹枯病菌(Rhizocto-nia cerealis),苗期活体测定了黄淮麦区57个小麦品种对3株不同菌系纹枯病菌的抗性,结果发现,被测品种苗期对3株纹枯病菌的抗性差异明显,不同来源纹枯病菌菌系之间的致病性存在分化现象。对兰考菌系R1的抗性:邯6172、花培3号等17个品种表现为中抗,兰考矮早8、百农AK58等24个品种为中感品种,其余16个品种为高感品种;对夏邑菌系R2的抗性:泛麦5号、郑麦98等10个品种表现为中感,其余47个为高感品种;对嵩县菌系R3的抗性:豫教2号、豫农949 2个品种为中感,其余55个均为高感品种。在所有被测品种中,没有发现免疫和高抗品种。  相似文献   
4.
无致病性双核丝核菌BNR-1的抑菌作用及温室防病效果   总被引:1,自引:0,他引:1  
通过平板对峙培养试验和温室防病试验,测定了双核丝核菌BNR-1的抑菌作用及对植物真菌病害的防治效果。结果表明,在PDA培养基上BNR-1对供试7种植物病原真菌均有不同程度的抑制作用,其中对苹果拟茎点霉的抑制作用最强,抑制率为83.9%。温室试验表明,BNR-1对小麦幼苗无致病性,对小麦纹枯病的防治效果达73.7%,较对照药剂井冈霉素提高13.2个百分点,处理间差异极显著(P<0.01)。  相似文献   
5.
中国北纬33度地区小麦纹枯病菌的群体组成及致病力研究   总被引:2,自引:0,他引:2  
为明确中国北纬33度地区小麦纹枯病病原菌的组成和致病力,对分离自江苏、安徽、河南、湖北4省的157株丝核菌,通过Hoechst 33258荧光染色法进行细胞核数量观测,利用菌丝融合的方法测定其所属融合群,并测定了其中111株丝核菌株对3个小麦品种(CI12633、陕229、扬麦158)麦苗的致病力.结果表明,在供试菌株中,150株为双核丝核菌,占95.54%,都属于AG-D融合群;7株为多核丝核菌,占4.46%,其中3株属于AG-1-IB融合群,3株属于AG11融合群,1株属于AG5融合群.供试菌株的致病力存在明显差异,双核丝核菌的致病力显著高于多核丝核菌,AG-D融合群中两种不同融合频率的菌株致病力无明显差异.不同地区的菌株间致病力无明显差异,菌株对3个小麦品种的致病力有显著差异,对CI12633致病力最强,对陕229致病力最弱,对扬麦158的致病力居中.  相似文献   
6.
大豆纹枯病与其种植密度的关系   总被引:1,自引:0,他引:1  
通过对大豆不同密度条件下大豆纹枯病的发生级别及普遍率的关系研究 ,发现大豆纹枯病的发生级别与普遍率都随着大豆密度的增加而增加 ,并提出防治大豆纹枯病的方法  相似文献   
7.
Sugarcane leaves and calli from highly susceptible and resistant varieties to eyespot disease were used to evaluate the Drechslera sacchari toxin effect at different concentrations and incubation times by measuring electrolyte leakage. This expression of disease resistance was observed not only in the leaf but also in the callus. Furthermore, the growth of resistant calli MS medium supplemented with DS toxin, was higher when compared to the susceptible ones. The possibility of obtaining resistant somaclones is confirmed.  相似文献   
8.
9.
小麦纹枯病抗性QTL的SSR标记研究   总被引:2,自引:0,他引:2  
以ARz/扬麦158F6重组自交系(RILs)群体为材料,对其纹枯病抗性进行SSR分析和初步的QTL分析。群体抗性分析结果表明:纹枯病抗性是由多个基因控制的数量性状;单个标记方差及回归分析显示有6个SSR标记至少在2份抗性资料中能被检测到,涉及2D、3A、3B、3D、7D5条染色体,能解释2.6%~10.1%的抗性表型变异。标记Xgwm340来源于感病品种扬麦158,其余的SSR标记(Xgwm102、Xgwm155、Xgwm71—2、Xgwm645、Xgwm437)来源于抗病亲本ARz;利用Map Manager QTX软件进行QTL分析,检测到2个QTL。  相似文献   
10.
Orodental disorders are common in equidae and can lead to serious clinical complications. This study determines the prevalence rate (PR) of orodental disorders in working donkeys in Egypt and their potential risk factors. During 4 years, 3,791 donkeys were examined in six Egyptian governorates. Full case history and thorough clinical and oral examinations were performed. Radiography and oroendoscopy were undertaken whenever possible. All data were statistically analyzed using Poisson generalized linear models to compare PR among governorates, sex, years, body condition score, and age groups and to determine the potential risk factors. Of 3,791 examined donkeys, 954 donkeys (25.17%) had orodental disorders. The PRs of acquired disorders were 9.81% sharp enamel points, 5.86% buccal ulcers, 4.88% hook, 4.70% overgrown teeth, 4.19% periodontal disease, 3.11% ramp, 2.60% dental caries, 2.37% dental calculus, 2.30% diastema, 2.06% step mouth, 2.00% soft tissue injuries other than buccal ulcers, 1.77% worn tooth, 1.37% loose tooth, 1.29% exaggerated transverse ridge, 1.24% fractured teeth, 0.82% missing teeth, 0.69% wave mouth, 0.50% molar table angle change, and 0.45% wolf tooth overgrowth. The PRs of the congenital disorders were 1.90% displaced teeth, 1.37% deviated teeth, 0.58% retained teeth, 0.16% overbite, 0.16% underbite, 0.11% supernumerary teeth, and 0.11% premolar cap. The risk factors significantly associated (P < .05) with the orodental disorders were age and sex of the animal, geographic location, and year of examination. This study provides a database for future studies on orodental disorders and for designing effective preventive and therapeutic strategies for these disorders in donkeys.  相似文献   
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