吕梁市设施黄瓜霜霉病绿色防控措施

针对黄瓜霜霉病菌的自身特点及其发病规律,探讨并实施了充分利用温室的密闭条件,通过科学的栽培管理措施,人为控制温室内的温、湿度,调节冬、春季节不同放风口,创造适宜黄瓜生长发育而不利于霜霉病发生发展的环境条件,控制霜霉病的发生为害,收到良好效果.     

芽孢杆菌对黄瓜霜霉病的防治效果研究

经黄瓜霜霉病孢子囊萌发抑制试验明确,芽孢杆菌菌株Z-X-3、Z-X-10对黄瓜霜霉病菌有较强拮抗作用。离体叶片法和温室防病试验表明,两菌株对黄瓜霜霉病有较好的防治效果,相对保护效果分别达46.42％、41.55％;治疗效果分别达46.30％、44.44％,高于农药克霜氰的31.81％、37.03％。     

太原市郊区黄瓜霜霉病菌对甲霜灵的抗药性检测

对太原市郊区黄瓜主要种植区黄瓜霜霉病菌对甲霜灵的抗药性进行了检测,结果表明:来自于8个不同地区的黄瓜霜霉病菌对甲霜灵的抗性频率均为100%。在检测的27个菌株中有2个中抗菌株,12个高抗菌株,13个特高抗菌株,无敏感菌株。     

沤肥浸渍液对黄瓜霜霉病的抑制作用及其机理

本文报道在温室条件下堆沤半年以上的各种家畜粪肥浸渍液对黄瓜霜霉病的防治效果及其机理初步研究,经3次重复试验得出:马粪沤肥浸渍液对黄瓜霜霉病的平均抑制率为67.33％,牛粪沤肥浸渍液对黄瓜霜霉病的平均抑制率为66.10％,羊粪、猪粪沤肥浸渍液也分别对黄瓜霜霉病有一定的抑制作用,但低于马粪、牛粪。马粪、羊粪沤肥浸渍液经100℃高温2h灭活后对黄瓜霜霉病仍有抑制作用,且抑制效果高于相应非灭活的沤肥浸渍液。经沤肥浸渍液处理的植株,叶绿素含量和过氧化氢酶活性均比对照明显增高,致使黄瓜抗病性增强。     

河北省和山东省黄瓜霜霉病菌对氟吡菌胺的抗性及常规药剂对黄瓜霜霉病的田间防效

为明确黄瓜霜霉病菌Pseudoperonospora cubensis对氟吡菌胺的抗性时空动态,2011—2016年从河北省和山东省黄瓜主产区采集1 821株霜霉病菌,采用叶盘漂浮法检测供试菌株对氟吡菌胺的敏感性,并以茎叶喷雾法评估5种常规药剂对黄瓜霜霉病的田间防效。结果表明,河北省和山东省黄瓜主产区的黄瓜霜霉病菌对氟吡菌胺已普遍产生了低度抗性,平均抗性倍数为5.86;所有供试菌株的抗性频率为51.89%,其中低抗菌株及中抗菌株分别占36.18%和15.71%;平均抗性指数为0.34,每年检测的抗性频率、抗性倍数及抗性指数呈增长趋势,且随着监测区域的变化而变化。在河北省定兴县和山东省寿光市进行的田间防效试验结果显示,按推荐剂量喷施,687.5 g/L氟吡菌胺·霜霉威盐酸盐SC对黄瓜霜霉病防效显著高于常规对照药剂68%精甲霜灵·代森锰锌WG、58%甲霜灵·代森锰锌WP、80%代森锰锌WP及250 g/L嘧菌酯SC的防效,但防效明显下降,由2011年的92.58%～93.31%降至2016年的80.07%～80.82%。表明需要制定和实施抗药性治理对策,如限制山东和河北2省黄瓜的每个生长季节中687.5 g/L氟菌·霜霉威SC的使用不超过2次,而且要与不同作用机理的卵菌杀菌剂交替使用防治黄瓜霜霉病。     

大棚甜瓜三种主要真菌病害拮抗细菌的筛选与鉴定

从甜瓜根际土壤、牦牛粪、蚯蚓粪等样品中分离出245株细菌,用平板对峙法筛选出14株对甜瓜枯萎病菌具有良好抑制作用的菌株,分别采用管碟法和凹玻片法测定拮抗细菌发酵液对甜瓜枯萎病的抑制效果和对甜瓜白粉病菌、甜瓜霜霉病菌孢子囊萌发的抑制效果。抑菌试验结果显示,菌株FCJ2发酵液对甜瓜枯萎病菌的抑制率为64.7%,对甜瓜白粉病菌、甜瓜霜霉病菌孢子萌发抑制率为62.3%、49.2%。盆栽试验结果显示,FCJ2对甜瓜枯萎病、甜瓜白粉病和甜瓜霜霉病的防效分别为88.5%、93.6%和82.6%,与农药对照组相比均具有显著差异(P0.05)。经形态特征鉴定、生理生化特征鉴定及16S rDNA序列分析,确定FCJ2为芽孢杆菌属枯草芽孢杆菌Bacillus subtilis。     

黄瓜霜霉病菌对双炔酰菌胺的敏感基线及其抗性突变体生物学性状研究

为建立黄瓜霜霉病菌对双炔酰菌胺的敏感基线及评估其抗性风险,采用叶盘漂浮法测定了采自河北、山东未使用过羧酸酰胺类(CAAs)药剂地区的69株黄瓜霜霉病菌(Pseudoperonospora cubensis)对双炔酰菌胺的敏感性,并对黄瓜霜霉病菌抗双炔酰菌胺突变体的获得方法及突变体的生物学性状进行了研究。结果表明:69株黄瓜霜霉病菌对双炔酰菌胺的平均EC50值为(0.358±0.144)μg/mL,不同敏感性菌株的频率呈连续单峰曲线分布,未发现敏感性下降的亚群体,因此可将其作为黄瓜霜霉病菌对双炔酰菌胺的敏感基线;通过药剂驯化的方法未获得黄瓜霜霉病菌抗双炔酰菌胺的突变体;而通过紫外诱导的方法获得了6个抗双炔酰菌胺的突变体,其抗性水平介于5.74~22.96倍之间,突变频率为1.09×10-7,适合度显著低于其亲本菌株,且抗药性不能稳定遗传;双炔酰菌胺与甲霜灵、嘧菌酯、霜脲氰、氟吡菌胺之间无交互抗性关系,与烯酰吗啉之间有交互抗性关系。据此推测黄瓜霜霉病菌对双炔酰菌胺的抗性风险为低到中等。     

烟草黄瓜花叶病的发生特点及防治措施

烟草黄瓜花叶病 (Cucumbermosaicvivus,CMV)为全世界烟草病毒病中最常见、流行最广泛的病害之一。 2 0 0 0年以来 ,黄瓜花叶病一直是湖北烟区的主要病害 ,该病毒由烟蚜等多种蚜虫传播 ,随着蚜虫的迁飞而流行 ,因此 ,发病流行速度快 ,来势迅猛。近年来随着我国种植结构调整 ,返季节蔬菜、林果类种植面积扩大 ,CMV越冬基数大 ,并且越来越靠近烟区 ,黄瓜花叶病发生有逐年加重的趋势。1　发生规律1 1　病状特点烟草移栽后开始发病 ,旺长期为发病高峰。发病初期表现“明脉”症状 ,后逐渐在新叶上表现花叶 ,病叶变窄 ,伸直呈拉紧状 ,叶表面茸…     

黄瓜霜霉病的发生特点与无公害防治技术

黄瓜霜霉病的发生越来越严重,减产一般在10%～20%,个别设施栽培黄瓜,减产达50%以上,严重影响菜农收入。通过对黄瓜霜霉病的发病症状、传播途径、发病条件的分析,提出有效的防治方法,遏制该病的为害。     

保护地甜瓜病害的发生原因及预防措施

甜瓜保护地栽培是一种主要的栽培形式,种植面积越来越大,病害的发生特别严重。为此,笔者将保护地甜瓜病害的发生原因及预防措施进行总结,介绍如下:1发病原因甜瓜病害的发生和流行,在大棚、温室内必须具备3个条件:易感病的甜瓜植株;一定数量的病原物;适宜发病的温、湿度等环境条     

A pattern in the appearance of cucumber powdery mildew in Dutch glasshouses

An inquiry was held in 1982, 1983 and 1984 to collect information on the survival and dispersal of cucumber powdery mildew. Growers who planted a crop in December, January or February were asked when they observed mildew for the first time in their crop. A gradual increase in the number of infected crops was observed from planting until May. The earliest observations of infected crops were immediately after planting. The weeks of the first observation of mildew, the disease-free periods and the apparent rates of increase of infected crops are presented for various districts. In the districts with the highest crop density (Pijnacker), mildew was generally observed early in the growing season, while the apparent rate of increase of infected crops was higher than in other districts. In the district with the lowest crop density (Northern Netherlands), mildew was observed late in the growing season and the apparent rate of increase of infected crops was low. Possible means of survival and dispersal of inoculum are discussed. It is suggested that overwintering of inoculum is possible because cucumber plants are grown all year round. Dispersal of cucumber powdery mildew is suggested to take place by transportation of infected planting stock, visitors and wind.     

Invasion of Phytophthora infestans at the landscape level: how do spatial scale and weather modulate the consequences of spatial heterogeneity in host resistance?

Strategic spatial patterning of crop species and cultivars could make agricultural landscapes less vulnerable to plant disease epidemics, but experimentation to explore effective disease-suppressive landscape designs is problematic. Here, we present a realistic, multiscale, spatiotemporal, integrodifference equation model of potato late blight epidemics to determine the relationship between spatial heterogeneity and disease spread, and determine the effectiveness of mixing resistant and susceptible cultivars at different spatial scales under the influence of weather. The model framework comprised a landscape generator, a potato late blight model that includes host and pathogen life cycles and fungicide management at the field scale, and an atmospheric dispersion model that calculates spore dispersal at the landscape scale. Landscapes consisted of one or two distinct potato-growing regions (6.4-by-6.4-km) embedded within a nonhost matrix. The characteristics of fields and growing regions and the separation distance between two growing regions were investigated for their effects on disease incidence, measured as the proportion of fields with ≥1% severity, after inoculation of a single potato grid cell with a low initial level of disease. The most effective spatial strategies for suppressing disease spread in a region were those that reduced the acreage of potato or increased the proportion of a resistant potato cultivar. Clustering potato cultivation in some parts of a region, either by planting in large fields or clustering small fields, enhanced the spread within such a cluster while it delayed spread from one cluster to another; however, the net effect of clustering was an increase in disease at the landscape scale. The planting of mixtures of a resistant and susceptible cultivar was a consistently effective option for creating potato-growing regions that suppressed disease spread. It was more effective to mix susceptible and resistant cultivars within fields than plant some fields entirely with a susceptible cultivar and other fields with a resistant cultivar, at the same ratio of susceptible to resistant potato plants at the landscape level. Separation distances of at least 16 km were needed to completely prevent epidemic spread from one potato-growing region to another. Effects of spatial placement of resistant and susceptible potato cultivars depended strongly on meteorological conditions, indicating that landscape connectivity for the spread of plant disease depends on the particular coincidence between direction of spread, location of fields, distance between the fields, and survival of the spores depending on the weather. Therefore, in the simulation of (airborne) pathogen invasions, it is important to consider the large variability of atmospheric dispersion conditions.     

山东省和河北省黄瓜霜霉病菌对烯酰吗啉及双炔酰菌胺的抗性监测

 为明确黄瓜霜霉病菌对烯酰吗啉及双炔酰菌胺的抗性时空动态及这两种药剂对黄瓜霜霉病的田间防效,采用叶盘漂浮法检测了2011~2016年采自河北省和山东省黄瓜主产区的霜霉病菌1 821个菌株对烯酰吗啉及双炔酰菌胺的敏感性,并采用茎叶喷雾法对这两种药剂的田间防效进行评估。结果表明:黄瓜霜霉病菌1 821个菌株对烯酰吗啉和双炔酰菌胺抗性频率分别为88.5%和34.3%,供试菌株中对烯酰吗啉的低抗菌株及对双炔酰菌胺的敏感菌株占优势,平均抗性倍数分别为8.92和2.44,抗性指数分别为0.42和0.27。黄瓜霜霉病菌对这两种药剂的抗性频率、抗性倍数及抗性指数随着监测年限及地域的不同而波动。在河北定兴和山东寿光日光温室进行的田间药效试验中,按照药剂田间推荐剂量喷施4次,50%烯酰吗啉可湿性粉剂和250 g·L^-1双炔酰菌胺悬浮剂对黄瓜霜霉病表现出良好的防效(85%以上),与两地黄瓜霜霉病菌对烯酰吗啉产生低抗、对双炔酰菌胺敏感的监测结果一致。由此推断,50%烯酰吗啉可湿性粉剂和250 g·L^-1双炔酰菌胺悬浮剂可在对甲霜灵(或精甲霜灵)、噁霜灵及嘧菌酯普遍产生抗性的地区,作为58%甲霜灵·代森锰锌WP、68%精甲霜灵·代森锰锌WG、64%噁霜灵·代森锰锌WP 和250 g·L^-1嘧菌酯SC的替代药剂单独使用或与不同作用机理的杀菌剂混用,防治黄瓜霜霉病。     

The Distribution and Spread of Sorghum Downy Mildew in Sorghum and Maize Fields in Nigeria and Zimbabwe

Sorghum downy mildew (Peronosclerospora sorghi, SDM) is a damaging disease of sorghum and maize crops in Africa. Runs analysis was used to study the distribution of systemically infected sorghum and maize plants in Nigeria and Zimbabwe. The temporal and spatial development of local lesions of SDM on sorghum in Zimbabwe was investigated by assessing the local lesion symptoms caused by conidia in plots with a single point source of inoculum. With ordinary runs analysis, there was evidence of clustering of disease in some fields in the humid areas of Nigeria and the semi-arid areas of Nigeria and Zimbabwe. Clustering was found in two of the eight runs analyses performed on maize in the humid south of Nigeria, and in only one of the eight runs in Zimbabwe, which was interpreted as a predominance of random infection at the time of assessment and at the spatial scales assessed. Symptoms of local lesions of SDM developed rapidly across plots from an introduced point source of infection. After 9 days-exposure to the source of inoculum, the incidence of diseased leaves was 1.2%, and after 50 days it was 74.5%. A disease gradient which initially developed flattened as the plot became uniformly diseased. The predominant wind direction was NNE, and most rapid spread of disease was towards the SSW and WSW. In conclusion, local lesions can spread rapidly in sorghum crops, suggesting that they may be an important source of conidial inoculum for further local and systemic infections during the growing season.     

北京地区花生病毒病及流行规律研究

1985—1987年研究表明北京地区花生上流行的病害主要有黄瓜花叶病毒CA株系(CMV-CA)引起的黄花叶病害和花生轻斑驳病毒(PMMV)引起的轻斑驳病害。血清鉴定451份花生病害样品,黄花叶病害样品受CMV-CA侵染占95.7％,轻斑驳病害样品受PMMV侵染占91.3％,中后期病害样品受CMV-CA和PMMV复合感染较普遍。CMV种传率2％左右,种传病苗在花生出苗后开始出现,6月病害进入高峰。三年CMV-CA流行程度明显不同,主要取决于苗期蚜虫发生早晚、发生量及苗期降雨量。PMMV种传率低于1％,病苗出现稍晚,但病害扩散快,6月上旬进入高峰,7月上、中旬发病率达100％。三年流行程度差异不明显。     

Peronosclerospora maydis found on maize, sweetcorn and plume sorghum in Far North Queensland

Symptoms of a downy mildew disease were recognized on maize growing in the Atherton Tableland and Lakeland Downs areas of Far North Queensland in 1985. Quarantine measures were invoked to prevent the spread of this potentially serious disease to other parts of Australia.
The pathogen was identified as Peronosclerospora maydis in 1986 following examination of conidiophores with conidia and host range studies. An alternative host was strongly suspected and a survey near fields where the disease had been prevalent led to the identification of P. maydis on Sorghum plumosum, a grass indigenous to northern Australia. All downy mildew outbreaks on maize and sweetcorn in northern Australia since 1970 have been in areas where S. plumosum occurs. It seems likely that P. maydis has been present in Australia for many years.     

Genetic diversity, aggressiveness and metalaxyl sensitivity of Pythium aphanidermatum populations infecting cucumber in Oman

Seventy three isolates of Pythium aphanidermatum obtained from cucumber from four different regions of Oman and 16 isolates of muskmelon from the Batinah region in Oman were characterized for aggressiveness, sensitivity to metalaxyl and genetic diversity using AFLP fingerprinting. Twenty isolates of P. aphanidermatum from diverse hosts from different countries were also included in the study. Most isolates from Oman were found to be aggressive on cucumber seedlings and all were highly sensitive to metalaxyl (EC₅₀ < 0·80 µg mL^?1). Isolates from cucumber and muskmelon were as aggressive as each other on both hosts (P > 0·05), which implies a lack of host specialization in P. aphanidermatum on these two hosts in Oman. AFLP analysis of all isolates using four primer–pair combinations resolved 152 bands, of which 61 (~40%) were polymorphic. Isolates of P. aphanidermatum from Oman and other countries exhibited high genetic similarity (mean = 94·1%) and produced 59 different AFLP profiles. Analysis of molecular variance indicated that most AFLP variation among populations of P. aphanidermatum in Oman was associated with geographical regions (F_ST = 0·118; P < 0·0001), not hosts (F_ST = –0·004; P = 0·4323). These data were supported by the high rate of recovery (24%) of identical phenotypes between cucumber and muskmelon fields in the same region as compared to the low recovery (10%) across regions in Oman, which suggests more frequent movement of Pythium inoculum among muskmelon and cucumber fields in the same region compared to movement across geographically separated regions. However, recovering clones among regions and different countries may imply circulation of Pythium inoculum via common sources in Oman and also intercontinental spread of isolates.     

沈阳地区葡萄霜霉病流行时间动态及其气象影响因子分析

 通过2012-2014年田间小区试验,对沈阳地区葡萄霜霉病自然发病情况进行了系统调查和对比分析,并对影响葡萄霜霉病流行动态的气象因素进行了相关性分析。结果表明,沈阳地区葡萄霜霉病的季节流行曲线是典型的单峰S形曲线。应用SPSS19.0软件分析,明确了Logistic模型能够反映沈阳地区葡萄霜霉病流行时间动态情况。同时,推导了病害流行阶段:指数增长期为7月上旬至7月下旬,该时期为最佳药剂防治时期;逻辑斯蒂增长期为7月下旬至8月下旬;衰退期为8月下旬至葡萄生育末期。不同生长季病害发生日期、流行阶段天数和最大病情指数虽各不相同,但与Logistic模型推导趋势基本一致。各个流行阶段病害的表观侵染速率表现为:始发期＞盛发期＞衰退期。始发期和盛发期的是决定整个生长季葡萄霜霉病流行程度的关键时期。气象因素对葡萄霜霉病的流行有明显影响,其中表观侵染速率与7 d平均相对湿度、7 d累计降雨量和7 d叶面湿润时数成显著正相关,而与7 d平均气温呈显著负相关,以上4个气象因素是影响沈阳地区葡萄霜霉病流行的主导因子。     

Movement of barley powdery mildew within field plots

Movement of barley powdery mildew (caused by Erysiphe graminis f.sp. hordei ) within fields was investigated by sowing the barley cultivars Tyra and Jupiter side by side in two field plots, and trapping spores along transects within the plots. The trapped spores were tested for virulence on the two cultivars. The epidemic on Tyra developed quickly, and a gradient in the proportion of spores with virulence on Tyra was detected in the Jupiter half-plots. In the Jupiter half-plots, the epidemic was much less severe; and no mildew could be found in one plot. Movement of spores from one half of the plot to the other usually declined steeply in the first 4 m from the boundary, and was not detectable beyond 12 m. There were exceptions where the gradient was much shallower, and these were consistent with differences in wind direction.     

广州地区黄瓜霜霉病流行速率的预测模型

通过对广州地区黄瓜霜霉病 4点 4年的系统调查 ,初步明确了该地区黄瓜霜霉病的发生规律 ,对该病的流行速率及其相关因子进行逐步回归分析 ,组建了广州地区黄瓜霜霉病流行速率的预测模型 ,利用历史数据对该模型进行检验 ,其预测 5d和10d的病情指数的准确度分别为88.16%和68.11% ;用该模型预测2000年黄瓜霜霉病的病情指数 ,其预测5d和10d的病情指数的准确度分别为94.47%和69.43%。