我国小麦秋苗条锈病发生规律及其区间菌源传播关系

全国冬小麦秋苗均可遭受来自西北和西南越夏区条锈菌的侵染与危害, 条锈菌在寄主上进一步繁殖和发展, 引起本地或者外地小麦条锈病流行。不同麦区秋苗条锈病发生时间、发生程度及其菌源传播规律各不相同, 年度间亦存在差异。根据小麦条锈病发生流行频率、病菌越冬和越夏情况、秋季菌源和春季菌源的有无与多少、提供时间及其影响范围与作用, 结合地理生态条件、气候特点、小麦种植区划与栽培模式等, 将中国小麦条锈病发生流行区域划分为8个明显不同的生态区系, 即关中、华北春季流行区; 成都平原、江汉流域冬季繁殖区; 西北、川西北越夏易变区; 云贵高原越夏冬繁区; 新疆冬春麦常发区; 西藏高原青稞、小麦常发区; 南方晚播冬麦偶发区; 内蒙古、东北春麦偶发区。通过病害实地调查、病菌群体遗传多样性和高空气流轨迹分析, 进一步揭示了区间菌源传播关系。陇南、陇中、陇东、宁南、海东、陕西宝鸡以及川西北和云贵高原等地区离越夏区较近, 冬小麦播种较早, 秋苗条锈病发生早、发病重, 秋季随西北气流传播到平原冬麦区和海拔较低的冬麦区侵染危害秋播麦苗, 其菌源数量对全国小麦条锈病发生流行程度起着至关重要的作用, 是中国小麦条锈病的秋季菌源基地, 面积约67万hm2; 成都平原、江汉流域、陕南、豫南、云贵坝区等麦区, 离条锈菌越夏区相对较远, 小麦播种期也较晚, 秋苗发病较晚较轻, 但冬季气候温和, 雨露条件充沛, 条锈菌在冬季可以不断侵染和繁殖, 在早春可积累大量菌源, 然后向北部和西部广大麦区扩散传播, 引起小麦条锈菌春季侵染, 是中国小麦条锈病的春季菌源基地, 面积约200万hm2。云贵高原越夏冬繁区可为我国广大麦区特别是长江中下游麦区提供部分菌源, 荆州等鄂东南地区是云贵菌源向长江下游麦区传播的中转站。云南与甘肃之间存在大量的基因流, 推测云南可能是中国小麦条锈菌重要的起源中心。西南和西北秋季菌源对长江流域麦区的相对重要性有待进一步研究明确。     

2002年我国小麦条锈病发生回顾

2002年小麦条锈病是继 1950年、1964年和 1990年后在全国范围内又一次大流行 ,其发生面积近 670万hm²,损失小麦约 10亿kg。发生区域涉及甘、陕、川、渝、云、贵、宁、鄂、豫、鲁、冀等 11个省 (市 )区。 2001年冬季和2002年春季气候适宜 ,以条中 32号小种为代表的毒性菌系的发展 ,使我国绝大部分主栽小麦品种不抗病 ,出现了条锈病发生早、发展快和发生重等特点 ,促成了 2002年我国小麦条锈病的流行。尽管 2002年条锈病发生范围广 ,但损失少于 1990年。提出了以品种抗病性利用及小麦抗病性变异和病菌群体动态监测、药剂和农业防治相结合 ,病害发生流行预测预报和条锈菌菌源基地治理为主的持续治理策略。     

2017年我国小麦条锈病流行特点及重发原因分析

2017年小麦条锈病在我国黄淮海麦区大范围流行, 表现出汉水流域及黄淮南部见病时间早、扩散速度快、黄淮海麦区流行范围广等特点。本文在系统总结2017年全国小麦条锈病流行特点的基础上, 分析认为极端暖冬气候、春季多雨适温气候条件和主产麦区缺乏抗性品种等因素是导致2017年我国小麦条锈病大流行的主要原因。     

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。     

1996年陇南麦区小麦条锈病发生特点及防治对策

１９９６年陇南麦区小麦条锈病再度流行危害，其流行态势迅猛，发生范围广，流行程度重，为１９９０年大流行以来最重的一年。新的毒性小种条中３０、３１号上升，导致生产品种抗性丧失；气象条件适宜；菌源量大等是今年小麦条锈病流行的主要因素。文中针对该区目前生产上利用的品种及后备品种（系）抗病性变异情况，提出了相应的对策     

陇南地区小麦条锈病发生动态与治理

1985～1990年作者对甘肃省陇南地区小麦条锈病秋苗菌源动态、越冬情况及其春季流行等进行了调查研究。结果表明,该地区秋苗发病重、越冬菌源多是导致春季小麦条锈病大流行的重要原因之一。海拔1600～1800m及其相邻的部份地区秋苗发病严重或较重,是发病基地或菌源基地,亦是治理的关键地区。其治理的配套关键技术包,括改制控害、抗病品种合理布局、适期晚播和粉锈宁拌种等都是行之有效的技术。其中通过改制,建立新的农业生态体系,兼与抗病品种合理布局和调节播期相结合,构成综合的生态治理工程,并不断优化,便有可能实现持久控害致富的目的。     

应用HYSPLIT-4模式分析小麦条锈病菌远程传播事例

 小麦条锈病的发生及大区流行与病原菌的远程传播密切相关。预测小麦条锈病大区流行的关键是搞清病原菌的远程传播路线和孢子云浓度变化规律。气流是菌源传播的主要动力,因此,气流运动的物理模型是对小麦条锈病菌远程传播事例分析的有力工具。本研究利用再分析格点资料(NCEP/NCAR Reanalysis Data),基于HYSPLIT-4模式,对历史上我国小麦条锈病菌远程传播的经典事例(分别发生于1960、1964、1975和1983年)进行了分析,着落区孢子浓度时间序列模拟结果与观察到病害发生前几天的降雨事件是相符的,结果表明小麦条锈病的远程传播及发生时间可通过计算大气环流运动来预测,病原菌孢子的沉降除由于孢子自身重力而引起的沉降外,很大程度上还受到降雨引起的湿沉降的影响。HYS-PLIT-4模式可用于探讨我国小麦条锈病区域间菌源传播关系问题,进行病害的预测预报,进一步指导我国小麦条锈病越夏和越冬调查以及菌源区综合治理和小麦品种布局。该研究在方法和技术上也可为研究其它病原菌远程传播提供借鉴。     

Evaluation of resistance of current wheat cultivars and breeding lines to stripe rust from three Gorges reservoir area

Nearly 100,000 ha in the Three Gorges Reservoir Area (TGRA) are in wheat production and the area is a junction where wheat stripe rust overwinters and causes epidemics the next spring; thus the area plays a pivotal role in wheat stripe rust epidemics in China. To better understand wheat resistance levels and the application of Yr genes in this area, 116 wheat cultivars (lines) were collected from the TGRA to investigate stripe rust resistance during the 2014–2016 cropping seasons. Seedling resistance evaluation results indicated that only nine accessions (7.8%) were immune or nearly immune to three predominant races of CYR32, CYR33 and PST-V26. In the field evaluation, 51 accessions (43.9%) showed adult-plant resistance, whereas 56 accessions (48.3%) were susceptible. The application of resistant sources focused on ineffective Yr9 (26.7%) and Yr17 (18.9%), and gradual ineffective Yr26 (34.5%), while effective Yr5, Yr10 and Yr15 were absent. Among them, 21 accessions (18.1%) were combined with two resistance genes. Both low resistance and more concentrated use of Yr genes indicated that this region faces a major risk for a wheat stripe rust epidemic. To improve the wheat resistance level in the TGRA, it is important to discover new all-stage resistance resources and diversify resistance resources for breeding.     

阿坝州小麦条锈病发生规律的研究

1979—1985年在四川省阿坝州越夏区进行条锈病发生规律调查。该地区海拔2900米以上的晚熟小麦约2.5万亩,条锈病持续发生至9月下旬,为自生麦苗和部分早播秋苗提供菌源。自生麦苗的发病面积近3万亩,其中休闲地约2.5万亩,主要分布在松潘、黑水2400—2900米地区,自生麦苗较多,发病较重;荞麦复种地约4000亩,主要分布在黑水、茂汶和汶川等地1700—2500米地带,自生麦苗较少,发病较轻。自生麦苗提供菌源的关键时期是9月上旬至10月下旬。秋苗发病面积约3.7万亩,主要分布在松潘、黑水2700—2950米地带,自9月中旬至12月下旬不断发生流行,而以8月中旬至9月中旬播种的秋苗发病较重,菌源较多,这在越夏菌源传播中起着很重要的作用。条锈菌在阿坝州又可越冬,构成周年侵染循环,常年流行,这不仅严重危害当地小麦生产,而且向广大冬麦区秋苗提供大量菌源。因此,综合治理阿坝州越夏区至关重要。     

Disease severity and pathotype dynamics of Puccinia striiformis f.sp. tritici in Denmark

Disease severity of wheat yellow rust, Puccinia striiformis f.sp. tritici , was analysed in Denmark from 1985 to 1999 in relation to the effects of weather on winter survival, distribution of host cultivars and pathotype dynamics. Below-average temperatures in January and February (midwinter) reduced yellow rust on the susceptible cv. Anja, and in three of four growth seasons following cold winters no yellow rust was observed on any cultivar under natural conditions. The agronomic consequences of dispersal of yellow rust urediniospores from external sources to Denmark, in a period during which large areas were planted with relatively few wheat cultivars, were demonstrated in several cases, most evidently when the Yr9 and Yr17 resistance genes became ineffective. Yr9 was overcome by the pathogen in a period with severe yellow rust epidemics on commercial cultivars, while virulence for Yr17 was first observed in a year with almost no yellow rust. In contrast, the resistance in cv. Kraka ( Yr1, CV ) was increasingly effective in controlling yellow rust, because pathotypes with the matching combination of virulence declined in the pathogen population. Pathotype frequency dynamics were thus influenced by selection forces within the country, and by selection forces in areas where spores were spread to Denmark from outside. The importance of a sufficient level of partial resistance in the wheat germplasm to prevent too much damage by yellow rust epidemics, in the event that the resistance genes are overcome by the pathogen population, is emphasized.     

陕西小麦条锈病发生面积预测模型

为提高陕西省小麦条锈病发生面积的预测准确度,以2010年-2018年陕西省小麦条锈菌冬繁区和越冬区的发生县区数、发生面积、温度和降雨量为数据集,通过Pearson相关性分析筛选病害流行的主要影响因子,利用全子集回归筛选病害流行的因子集。以筛选得到的影响病害流行的5个因子,即累计发生县区数、冬繁区条锈病发生面积、1月平均温度、1月平均降雨量和3月平均降雨量为自变量,采用全子集回归和BP神经网络算法开展小麦条锈病发生面积的预测研究。结果表明,全子集回归和BP神经网络算法对2019年-2020年的小麦条锈病发生面积预测准确度均达90%以上,预测2021年陕西省小麦条锈病发生面积分别为46.11万hm~2和52.85万hm~2。     

Major genetic changes in wheat with potential to affect disease tolerance

ABSTRACT Selection through plant breeding has resulted in most elite winter wheat germplasm in the United Kingdom containing the Rht-D1b semi-dwarfing allele, the 1BL.1RS chromosome arm translocation with rye, and an allele conferring suppression of awns. Near-isogenic lines (NILs) were used to test whether these major genetic changes have had any effect on disease tolerance. The ability of the NILs to tolerate epidemics of Septoria leaf blotch or stripe rust was measured in four field experiments over two seasons. Tolerance was quantified as yield loss per unit of green canopy area lost to disease. There was a trend for the presence of the 1BL.1RS translocation to decrease tolerance; however, this was not consistent across experiments and there was no effect of semi-dwarfing. The awned NIL exhibited decreased tolerance compared with the unawned NIL. There were significant differences in tolerance between the cultivar backgrounds in which the NILs were developed. Tolerance was lower in the modern genetic background of Weston, released in 1996, than in the genetic background of Maris Hunstman, released in 1972. The data suggest that certain physiological traits were associated with the tolerance differences among the backgrounds in these experiments. Potential yield, accumulation of stem soluble carbohydrate reserves, and grain sink capacity were negatively correlated with tolerance, whereas flag leaf area was positively correlated.     

Velocity of spread of wheat stripe rust epidemics

ABSTRACT Controversy has long existed over whether plant disease epidemics spread with constant or with increasing velocity. We conducted largescale field experiments with wheat stripe rust at Madras and Hermiston, Oregon, where natural stripe rust epidemics were rare, to test these competing models. Data from three location-years were available for analysis. A susceptible winter wheat cultivar was planted in pure stand and also in a 1:4 or 1:1 mixture with a cultivar immune to the stripe rust race utilized in the experiments. Plots were 6.1 m wide and varied from 73 to 171 m in length. A 1.5 by 1.5-m focus was inoculated in either the center (2001) or upwind of the center (2002 and 2003) of each plot. Disease severity was evaluated weekly throughout the epidemics in each plot at the same points along a transect running upwind and downwind from the focus. Velocity of spread was calculated from the severity data and regressed separately on time and on distance from the focus. In all location-years and treatments, and at all levels of disease severity, velocity consistently increased linearly with distance, at an average rate of 0.59 m/week per m, and exponentially with time. Further, across epidemics there was a significant positive relationship between the apparent infection rate, r, and the rate of velocity increase in both space and time. These findings have important implications for plant diseases with a focal or partially focal character, and in particular for the effectiveness of ratereducing disease management strategies at different spatial scales.     

林芝地区小麦条锈菌转主寄主小檗的鉴定与分布

西藏自治区是我国小麦条锈病发生与流行相对独立的一个区系,小麦条锈病是严重影响西藏小麦安全生产的重要病害之一,林芝地区是西藏自治区小麦条锈病重要的常发区和流行区。已有研究证实,小檗是小麦条锈菌的转主寄主之一,并在我国小麦条锈菌致病性变异产生新菌系和小麦条锈病的发生过程中起作用。林芝地区小檗种类较多,但目前对林芝地区小檗是否能作为小麦条锈菌的转主寄主缺乏相关的研究和报道。本文针对小麦条锈病常发区的西藏林芝地区小檗资源进行了调查,对小檗能否作为小麦条锈菌转主寄主进行了鉴定。结果表明6种小檗在林芝地区常见且分布广泛,均是小麦条锈菌的转主寄主。这对进一步研究西藏小麦条锈病的发生、流行与病原菌致变性变异起着重要作用。     

The combined effects of multiple diseases and climatic conditions on thousand kernel weight losses in winter wheat

Thousand kernel weight (TKW) is a yield component associated with grain quality. It is reported in the literature that TKW is significantly influenced by varieties, agro-ecological conditions and disease indices, but the influence of their interactions on TKW loss has rarely been taken into consideration. The main objective of this study was to examine the combined effects of multiple diseases and climatic conditions on TKW losses in winter wheat. Leaf rust, powdery mildew, and Septoria tritici blotch were considered biotic predictor variables in regression models explaining TKW losses. Monthly averages of temperature, relative humidity and total rainfall in May and June in the 2006–2013 growing seasons were used as abiotic predictor variables. The results of this study indicated a significant low positive correlation between yield loss and TKW loss in the two varieties. TKW losses were less influenced by leaf rust, powdery mildew, and Septoria tritici blotch than yield losses. The significant influence of the interaction between variety and the environmental conditions on TKW loss was confirmed from the general linear model function. The results of this study indicated that factors influencing yield and yield component losses are part of the complex environment, and the relationship between them should be investigated with respect to their interactions.     

Disease-weather relationships for powdery mildew and yellow rust on winter wheat

Key weather factors determining the occurrence and severity of powdery mildew and yellow rust epidemics on winter wheat were identified. Empirical models were formulated to qualitatively predict a damaging epidemic (>5% severity) and quantitatively predict the disease severity given a damaging epidemic occurred. The disease data used was from field experiments at 12 locations in the UK covering the period from 1994 to 2002 with matching data from weather stations within a 5 km range. Wind in December to February was the most influential factor for a damaging epidemic of powdery mildew. Disease severity was best identified by a model with temperature, humidity, and rain in April to June. For yellow rust, the temperature in February to June was the most influential factor for a damaging epidemic as well as for disease severity. The qualitative models identified favorable circumstances for damaging epidemics, but damaging epidemics did not always occur in such circumstances, probably due to other factors such as the availability of initial inoculum and cultivar resistance.     

Predicting severity of asian soybean rust epidemics with empirical rainfall models

ABSTRACT Although Asian soybean rust occurs in a broad range of environmental conditions, the most explosive and severe epidemics have been reported in seasons with warm temperature and abundant moisture. Associations between weather and epidemics have been reported previously, but attempts to identify the major factors and model these relationships with field data have been limited to specific locations. Using data from 2002-03 to 2004-05 from 34 field experiments at 21 locations in Brazil that represented all major soybean production areas, we attempted to identify weather variables using a 1-month time window following disease detection to develop simple models to predict final disease severity. Four linear models were identified, and these models explained 85 to 93% of variation in disease severity. Temperature variables had lower correlation with disease severity compared with rainfall, and had minimal predictive value for final disease severity. A curvilinear relationship was observed between 1 month of accumulated rainfall and final disease severity, and a quadratic response model using this variable had the lowest prediction error. Linear response models using only rainfall or number of rainy days in the 1-month period tended to overestimate disease for severity <30%. The study highlights the importance of rainfall in influencing soybean rust epidemics in Brazil, as well as its potential use to provide quantitative risk assessments and seasonal forecasts for soybean rust, especially for regions where temperature is not a limiting factor for disease development.     

四川省小麦条锈病流行区划及菌源传播路径分析

四川省是我国小麦条锈病菌Puccinia striiformis Westend f.sp.tritici Eriks的菌源地和常发区,近10年秋苗病害始见期提前、流行期加长、危害损失呈上升趋势.在实地调查基础上,利用GIS技术对全省132个小麦主产县(市、区)1987-2006年小麦条锈病发生情况进行系统分析.结果表明,四川省小麦条锈病流行区域可划分为川西北越夏区、川西南越夏及冬繁区、盆地冬繁区和川东南春季流行区.GIS软件分析发现病菌孢子在四川盆地内的传播路径为沿岷江、涪江、沱江和嘉陵江等4条河流自北向南、自西向东传播.     

Surveys of cereal diseases and pests in the Netherlands. 4. Occurrence of powdery mildew and rusts in winter wheat

Results of annual surveys of winter wheat fields from 1974 to 1986 were compiled to describe epidemics of powdery mildew and rusts in relation to weather and cultivar resistance.An average of 29 and 70% of fields were infected by powdery mildew in May and July, respectively. Mildew prevalence in May was positively correlated with average temperature in October and with average temperature over the months December, January, February and March. In addition, it was correlated negatively with the average grade of mildew resistance of the cultivars sown each year. Prevalence of mildew in July did not show consistent correlations with weather characteristics nor with mildew prevalence in May.Yellow rust was usually not detected in May and on average 18% of the fields was infected in July. The occurrence of yellow rust decreased after 1977, when the farmers adopted cultivars resistant or moderately resistant to yellow rust.Brown rust was usually not detected in May, while in July on average 48% of the fields was infected. Brown rust intensity in July was high in years with a high March temperature and high precipitation during April and May.Black rust was rare in the Netherlands, with 3 and 1% of the fields infected in July 1977 and 1981, respectively.     

小麦条锈病药剂防治试验

1962年和1963年,分别在信阳和郑州进行三次田间药剂防治小麦条銹病試驗結果表明:在叶面防治效果方面,超过0.5％对氨基苯磺酸10％以上的有0.5％与0.3％“閩农五号”、氟化鈉600倍、1000倍、氟矽酸鈉600倍、1％氨基苯磺酸鈉、1％氨基苯磺酸鋅、1％氨基苯磺酸鎳、0.1％与0.2％氮化鎳、0.2％氟化鎳及0.2％醋酸鎳等12种;超过1—10％或基本上相等的有1％常州氟鋇、1％氨基苯磺酸铁、0.1％与0.2％硫酸鎳四种;其中药效較好而又无药害、比对照增产10—35％的有1％氨基苯磺酸鈉、0.5—1％常州氟鋇、0.3—0.5％“閩农五号”、0.5％氨基苯磺酸铁及0.5％对氨基苯磺酸等;药效尚好而药害輕微、比对照增产10—20％的有1％氨基苯磺酸铁盐、0.5％鋅盐、0.5％鎳盐、0.1％醋酸鎳及氟矽酸鈉600倍等。田間药剂防治的适当时期和次数,根据病情动态和噴药效果分析,在河南省中南部地区建議以小麦的孕穗初、孕穗末或抽穗初、揚花期三次噴药为最好,灌浆以后噴药一般不起作用,如早春气温较高,病情上升迅速,則可在拔节期加噴一次。