86份贵协系小麦种质资源对条锈病的抗病性评价

小麦条锈病是发生于甘肃陇南麦区小麦生产上的最主要病害,利用和种植抗病品种(系)是防治该病害最经济有效且有利于保护环境的措施。2011-2013年度连续两年在甘肃省农业科学院植物保护研究所甘谷试验站田间对86份来自贵州大学的贵协系小麦种质资源材料进行了成株期抗条锈病鉴定,结果发现仅有‘贵协1’、‘贵协2’、‘贵协3’、‘贵协7’、‘贵协011-2-6’、‘贵协011-3-16’、‘贵协011-3-29’、‘贵协011-3-31’、‘贵协011-3-34’等9份材料表现抗病,且抗病性相对稳定,可作为一线抗源材料在陇南抗病育种中充分利用。     

小麦条锈菌有性生殖与毒性变异的研究进展

小麦条锈病是由条形柄锈菌小麦专化型Puccinia striiformis f.sp.tritici Erikss.et Henn.引起的、最具毁灭性的小麦真菌病害之一,在全世界小麦种植的国家或地区均有发生,其流行常常导致小麦严重的产量损失。利用抗病品种是防治小麦条锈病最为经济、有效的措施。然而,由于病原菌毒性变异不断产生新小种,频繁导致品种抗病性"丧失",继而引发病害流行成灾。小麦条锈菌的有性阶段过去一直未被发现,有性生殖与条锈菌变异及其在病害发生中的作用研究一直处于空白状态。近年来,随着小麦条锈菌转主寄主的发现,国内外学者开展了相关的研究工作,取得了一系列重要的研究进展。本文综述了小麦条锈病的发生症状、病菌的生物学特性、转主寄主、有性生殖与条锈菌毒性变异、转主寄主在条锈病发生中的作用、影响有性生殖发生的因素等方面的最新进展,并展望了深入开展小麦条锈菌有性生殖的研究思路。     

辽河流域小麦白粉病综合治理体系

在田间,通过不同时期人工接种小麦条锈病菌和施用杀菌剂三唑酮的组合,测定小麦叶内三唑酮及其代谢产物三唑醇含量对病害相对侵染几率,潜育期,病斑扩展,产孢面积及传染期等组分的定量影响。结果表明,施药后不同批次接种,在一定时间内,麦叶内药剂可降低病害相对侵染几率并延长其潜育期;接种后施药在一个潜育期内,药剂可使病害潜育期提早。     

诱导小麦抗叶锈病生防细菌的筛选、鉴定及其防效评价

小麦叶锈病是小麦生产上的重要病害,防治该病害主要采用抗病品种和喷施化学农药,而探索生物防治是防治该病的一种新方法。本研究使用3株细菌菌悬液对小麦种子进行处理,于小麦一叶期接种叶锈病菌10d后调查其发病率和严重度。结果表明,在盆栽试验中,Sneb1462菌株菌悬液诱导小麦抗叶锈病的效果最好,可使发病率和严重度比对照分别降低27.54%和49.90%;Sneb1462还可促进小麦根部生长,施用后小麦根长和地下部鲜重分别比对照提高30.19%和29.03%。在大田试验中,用Sneb1462菌悬液处理小麦种子后叶锈病的严重度降低38.60%,小麦株高和穗重分别提高16.44%和34.98%,表明该菌株是一株优良的抗病促生菌。经透射电镜观察、16SrDNA序列分析及生理生化的检测,鉴定该菌株为多黏类芽胞杆菌Paenibacillus polymyxa。利用生防细菌Sneb1462进行种子处理防控小麦叶锈病将是一种新型的植保措施,具有重要的研究意义。     

Glyphosate reduces urediniospore development and Puccinia psidii disease severity on Eucalyptus grandis

BACKGROUND: Recent studies have shown the effects of glyphosate drift on decreasing rust intensity on Eucalyptus grandis plants. However, the effects of the herbicide on Puccinia psidii initial development are unknown. In this study the systemic action of glyphosate on rust severity was evaluated on Eucalyptus plants maintained under greenhouse conditions. Urediniospore germination and apressorium formation on detached leaves and on water agar medium, previously treated with glyphosate, were also evaluated. RESULTS: Rust severity and the number of urediniospores per leaf area were significantly reduced with increasing glyphosate doses, even on branches not directly treated with the herbicide, indicating a systemic effect of glyphosate on pathogen development. Similarly, higher glyphosate doses also reduced germination and apressorium formation on detached Eucalyptus leaves, regardless of the direct application of the product on the leaf limb or on the petiole base. Puccinia psidii urediniospore germination in water agar medium also decreased with increasing herbicide doses. CONCLUSIONS: Reductions in germination and apressorium formation of P. psidii urediniospores with increasing glyphosate dose indicate that a lower severity and intensity of the disease may perhaps be due to blockage of the shikimic acid pathway in the fungal metabolic system. Copyright © 2011 Society of Chemical Industry     

BION诱导小麦幼苗抗叶锈病研究

研究了BION（有效成分为苯并噻二唑,BTH）对小麦幼苗叶锈病的诱导抗性与苯丙氨酸解氨酶（phenylalanine ammonia lyase,PAL）、多酚氧化酶（polyphenoloxidase,PPO）和过氧化物酶（peroxidase,POD）活性的关系.结果表明：BION诱导麦苗抗叶锈病的最佳浓度为200 mg/L;在诱导处理和接种之间至少需要2天才能诱导抗性表达,间隔4天的诱导抗性效果最好,这种抗性的持久期至少14天.BION处理麦苗第1叶,可使未处理的第2叶也表现出抗性,但处理后至少需要48h这种抗性才能表达.以浓度为200mg/L的BION处理小麦叶片4天后接种,PAL、PPO、POD的活性均高于对照,在接种2天后产生一个峰值,BION水溶液对小麦叶锈菌夏孢子的萌发无明显抑制作用.由此认为,BION可诱导小麦幼苗产生对叶锈病的系统获得抗性.     

Cytochrome b gene structure and consequences for resistance to Qo inhibitor fungicides in plant pathogens

The cytochrome b (cyt b) gene structure was characterized for different agronomically important plant pathogens, such as Puccinia recondita f sp tritici (Erikss) CO Johnston, P graminis f sp tritici Erikss and Hennings, P striiformis f sp tritici Erikss, P coronata f sp avenae P Syd & Syd, P hordei GH Otth, P recondita f sp secalis Roberge, P sorghi Schwein, P horiana Henn, Uromyces appendiculatus (Pers) Unger, Phakopsora pachyrhizi Syd & P Syd, Hemileia vastatrix Berk & Broome, Alternaria solani Sorauer, A alternata (Fr) Keissl and Plasmopara viticola (Berk & Curt) Berlese & de Toni. The sequenced fragment included the two hot spot regions in which mutations conferring resistance to QoI fungicides may occur. The cyt b gene structure of these pathogens was compared with that of other species from public databases, including the strobilurin-producing fungus Mycena galopoda (Pers) P Kumm, Saccharomyces cerevisiae Meyer ex Hansen, Venturia inaequalis (Cooke) Winter and Mycosphaerella fijiensis Morelet. In all rust species, as well as in A solani, resistance to QoI fungicides caused by the mutation G143A has never been reported. A type I intron was observed directly after the codon for glycine at position 143 in these species. This intron was absent in pathogens such as A alternata, Blumeria graminis (DC) Speer, Pyricularia grisea Sacc, Mycosphaerella graminicola (Fuckel) J Schr?t, M fijiensis, V inaequalis and P viticola, in which resistance to QoI fungicides has occurred and the glycine is replaced by alanine at position 143 in the resistant genotype. The present authors predict that a nucleotide substitution in codon 143 would prevent splicing of the intron, leading to a deficient cytochrome b, which is lethal. As a consequence, the evolution of resistance to QoI fungicides based on G143A is not likely to evolve in pathogens carrying an intron directly after this codon.     

黄帚橐吾提取物对棉铃虫的生物活性

为掌握贵州甘蔗真菌病害种类及发生情况,采用随机踏查、定点调查、症状诊断与病原菌形态特征观察等方法对贵州甘蔗产区7个县进行真菌病害调查;采用菌丝生长速率法,对甘蔗褐斑病进行了5种杀菌剂室内毒力测定和田间防效试验。结果表明,贵州甘蔗主要真菌病害有褐斑病、褐锈病、赤腐病、黄斑病、轮斑病、褐条病、煤烟病、黑穗病,其中褐斑病、轮斑病、褐条病发生较重,煤烟病发生严重;5种杀菌剂中,325 g/L苯甲· 嘧菌酯悬浮剂对甘蔗褐斑病毒力最高和防效最好,EC50为0.0025 mg/L,第3次药后10 d防效达86.46%。其他4种杀菌剂对褐斑病均有较好的防治效果,可应用于甘蔗生产防治褐斑病。     

10份小麦持久抗性资源和6份新品系抗条锈病的遗传特点分析

小麦条锈病是长期威胁我国小麦生产安全的重要气传病害.由于病原菌(Puccinia striiformisf.sp.tritici,Pst)群体毒性结构高度变异,我国小麦条锈病防治工作经常面临严峻挑战.培育和广泛利用抗病品种是防治小麦条锈病最为经济有效的措施.因此,鉴定抗源和探究持久抗病基因型的遗传模式能为抗病育种提供抗...     

特谱唑防治小麦锈病毒理与应用技术的初步研究

据室内测定结果,特谱唑具有很强的内吸传导性能,用灌土法施药的效果可与叶面喷雾法相比拟,但基本上是向上传导。此药具有很强的治疗和铲除作用,在病菌潜育期施药,可控制到不发病,最多只显退绿斑;在退绿期施药,可使病菌夏孢子堆变成褐色小点,孢子粉极少,但对夏孢子的萌发影响则弱。此药剂比三唑酮毒力强,其毒力指数(三唑酮为100)都在900以上,即达到 EC_(50)和 EC_(95)所需的剂量,前者只需后者的11%以下,特别是保护作用突出。据田间试验结果,此药剂的用药量比三唑酮少,如控制条锈病为害所需的剂量只要三唑酮的三分之一。防治条锈病的用药量一般以45—47g/ha(有效成分)为合适;用药期以病叶率5%—10%、小麦处于旗叶伸长期为宜;施药次数以上述的合适剂量和适期喷施1次即可控制整个成株期条锈病为害,收到最佳的经济效益。     

Recent outbreaks of rust diseases and the importance of basic biological research for controlling rusts

Rust fungi are obligate plant parasites belonging to the order Pucciniales; they comprise about 7,800 species throughout the world. Some species seriously damage crops, vegetables, fruits and trees. Of these species, wheat stem rust (Puccinia graminis f. sp. tritici), Asian soybean rust (Phakopsora pachyrhizi) and myrtle rust (Puccinia psidii) have recently become major concerns worldwide, and this review, discusses recent rust disease outbreaks of Asian soybean rust and myrtle rust. Both rusts have very wide host ranges. Asian soybean rust has spread from its original region of distribution (eastern Asia) to many areas of soybean cultivation around the world. Myrtle rust is a new disease in areas where host plants were first introduced and has spread to other parts of the world including the areas where the host plants are indigenous. New diseases of economically important plants can occur by host shifts from wild host plants or host jumps from phylogenetically unrelated plant species. Recent advances in molecular phylogenetic studies have contributed to a revision of rust taxonomy. Molecular phylogenetic analyses, together with precise morphological observations and inoculation experiments, have identified taxonomic groups among populations that are morphologically very similar. Systematic, ecological and other basic biological studies of rust fungi in both cultivated and wild host plants are very important for developing methods to control rust diseases. Recent changes in the International Code of Botanical Nomenclature will surely affect the systematics of rust fungi.     

On the epidemiological evaluation of fungicide action

When plant disease control chemicals are partially effective, an epidemiologic analysis of antifungal action may be needed. The life table method is advocated to this purpose. It permits a complete analysis of a monocyclic experiment, and it predicts the maximum relative growth rate of the fungal population in a polycyclic field situation. The life table method, which also determines age-dependent effects of disease control chemicals, can be adapted for use in computer simulation models of plant disease epidemics. An example of the life table method is given comparing a cultivar of wheat resistant to Puccinia recondita (the ‘treated’) with one susceptible (the ‘untreated’) to brown leaf rust of wheat (Triticum aestivum).     

我国40个小麦品种抗叶锈性研究

 选用11个具不同毒性基因组合的叶锈菌致病类型推导分析了1998~1999年度国家小麦区域试验40个品种所携带的抗叶锈病基因状况。在供试的39个已知抗叶锈基因(或基因组合)中,推导出Lr1、Lr2c、Lr3bg、Lr10、Lr13、Lr14a、Lr16、Lr23、Lr26、Lr32等10个抗叶锈基因,分布在24个品种中,有11个品种携带未知抗叶锈基因,5个品种不具有苗期抗叶锈基因。选用BBB、DHS、PGT和PHT等4个叶锈菌致病类型并设置5/10℃、15/20℃、25/30℃(黑暗/光照)3种不同的温度条件,研究了40个供试品种的抗性稳定性。结果表明,在这些品种中有15个品种的侵染型表现稳定或较稳定,3个品种表现为高温抗性,2个品种表现低温抗性,其余20个品种存在明显的品种、菌系和温度三者的相互作用;利用6个叶锈菌混合优势小种在田间进行成株期抗叶锈性鉴定结果表明,在40个供试品种中有21个品种具有良好的抗性,其中,至少有6个品种表现为慢锈性,有4个品种表现为明显的成株抗性,有4个品种可能携带成株抗性基因Lr34。文中还对几个主要抗叶锈基因的抗性特点及其利用价值等进行了讨论。     

Synthesis of benzylaminopyrimidines and their fungicidal activities against wheat brown rust and barley powdery mildew

Members of a new class of fungicide containing benzylaminopyrimidine as a core structure were synthesized and their fungicidal potencies against wheat brown rust, Puccinia recondita, and barley powdery mildew, Erysiphe graminis, were assessed. Among these fungicides, N-(fluoroalkoxy or fluorophenoxybenzyl)-4-pyrimidinamines showed notable preventive activities. The potency of the new pyrimidines was increased when a difluoromethoxy or tetrafluorophenoxy group was introduced at the 4- or 3-position of the phenyl moiety and a methyl or ethyl group was introduced at the benzyl position. Structure–activity relationships are discussed. © 1998 Society of Chemical Industry     

鲜食玉米南方锈病发生动态及药剂防控

田间条件下采用目测法调查了由多堆柄锈菌(Puccinia polysora Underw.)引起的南方锈病在广州鲜食玉米产区的发生动态,并测试了锈病对鲜食玉米产量的影响及几种药剂对南方锈病的防治效果。结果表明,南方锈病在鲜食玉米生产期间持续危害,7月份和11月份发生最严重,发病率近100%。锈病危害直接造成鲜食玉米果穗净重降低,重度危害(危害严重度50%)比轻度危害(危害严重度30%)折合每667m2产量减少47.6kg。化学药剂对南方锈病具有抑制作用,其中125g/L氟环唑SC和250g/L吡唑醚菌酯EC的防治效果最好,处理后锈病危害严重度比对照分别降低63.04%和57.21%,可挽回产量损失8%以上。     

43个中国小麦品种(系)抗叶锈性研究

 选用12个墨西哥叶锈菌生理小种对43个中国小麦品种(系)所携带的抗叶锈病基因进行了推导,在25个品种(系)中推导出6个抗叶锈基因Lr1,Lr10,Lr13,Lr14a,Lr16和Lr26,9个品种(系)对本试验所使有的12个叶锈菌生理小种都表现感病反应,另有9个品种(系)携带未知的抗叶锈基因。在墨西哥2个地点进行的田间成株期抗叶锈性试验表明,12个品种(系)表现慢叶锈性,在将来的抗病育种中有一定的应用价值。     

Glyphosate-resistant horseweed made sensitive to glyphosate: low-temperature suppression of glyphosate vacuolar sequestration revealed by 31P NMR

BACKGROUND: Horseweed has been the most invasive glyphosate‐resistant (GR) weed, spreading to 16 states in the United States and found on five continents. The authors have previously reported that GR horseweed employs rapid vacuolar sequestration of glyphosate, presumably via a tonoplast transporter, substantively to reduce cytosolic glyphosate concentrations. 1 It was hypothesized that glyphosate sequestration was the herbicide resistance mechanism. If resistance is indeed endowed by glyphosate sequestration, suppression of sequestration offers the potential for controlling GR horseweed at normal herbicide field‐use rates. RESULTS: Low‐temperature ³¹P NMR experiments performed in vivo with GR cold‐acclimated horseweed showed markedly suppressed vacuolar accumulation of glyphosate even 3 days after glyphosate treatment. [In stark contrast, 85% of the visible glyphosate was sequestered 24 h after spraying warm‐acclimated GR horseweed.] Cold‐acclimated GR horseweed treated at normal use rates and maintained at low temperature succumbed to the lethal effects of glyphosate over a 40 day period. Treatment of GR horseweed in the field when temperatures were cooler showed the predicted positive herbicidal response. CONCLUSIONS: Low temperature markedly diminishes vacuolar sequestration of glyphosate in the GR horseweed biotype, yielding a herbicide response equivalent to that of the sensitive biotype. This supports the recent hypothesis 1 that glyphosate sequestration is the resistance mechanism employed by GR horseweed. Copyright © 2011 Society of Chemical Industry     

The ubiquity of non-specific eliciting activity in intercellular washing fluids from rust-infected wheat leaves

Intercellular washing fluids (IWF) were harvested from a range of wheat cultivars infected with either the leaf rust fungus ( Puccinia recondite f.sp. tritici ) or the stem rust fungus ( Puccinia graminis f.sp. tritici ). These fluids were then tested for their ability to elicit symptoms of chlorosis and necrosis in 14 wheat cultivars. Eliciting activity was found in all samples tested, irrespective of both the host cultivar infected by the rust fungus and the genotype of the infecting pathogen isolate. Healthy test cultivars either responded to all IWF preparations or were responsive to none of them. Investigations into the nature of this non-specific eliciting activity revealed that active molecules are periodate sensitive, negatively charged at neutral pH, and associated with a high molecular weight fraction.     

小麦条锈病抗病遗传及菌源基地基因布局研究进展

小麦条锈病是世界范围内严重影响小麦生产安全的重要病害。我国是世界上最大的小麦条锈病流行区,自成独立的流行体系。培育和种植抗病品种是防治病害最有效的措施。然而,小麦品种对条锈病的抗性常常由于病菌新小种的产生而丧失,这既是一个重大科学问题,也是一个亟待研究解决的生产实际问题。如何有效、合理地利用小麦的抗病性,植病学家和育种学家进行了一个多世纪的研究与探索,提出了各种理论与策略,开展了各种实践与探索。该文就小麦抗条锈病遗传及其基因布局研究进展进行综述,主要包括抗性鉴定评价、抗病基因发掘与利用、数量抗性位点定位、抗病基因克隆与功能解析、近等基因系创建与应用,以及抗源创制、抗病生态育种和大区基因布局等,并对深入开展抗条锈病基因发掘与利用和大区基因布局进行展望,以期为抗病育种和病害持续治理提供参考。     

河南省小麦条锈病越夏规律初步研究

鉴于近年小麦条锈病在河南省发生为害新特点,为了弄清该病病菌是否能在本省越夏,为开展综合防治提供理论依据,于2004～2009年进行了本项研究工作。调查研究结果证明,小麦条锈病病菌能在本省豫北、豫西海拔1 100 m以上地区越夏。越夏后的条锈病病菌能侵染当地和豫西南地区的小麦秋苗,引起冬前发病和春季流行。自生麦苗是条锈病病菌越夏的主要寄主。