CARAH预警模型在马铃薯晚疫病防治药剂减量增效中的应用

为明确CARAH预警模型对四川马铃薯晚疫病防治药剂减量增效技术的指导效果,针对马铃薯晚疫病感病品种兴佳2号和中薯2号,利用CARAH预警模型监测马铃薯晚疫病的发生和流行。结果表明,中心病株主要在马铃薯晚疫病第3代侵染循环出现,其中秋马铃薯晚疫病发生程度较春马铃薯晚疫病重,且流行速度快。据此,在马铃薯晚疫病第2代第1次侵染循环5分值时减量使用防治药剂,减量处理均表现出较高的防治效果。其中,一个常规用量减量33%的处理(即10%氟噻唑吡乙酮OD 225 mL/hm~2施用2次、间隔14 d)经济效益增幅最高。     

马铃薯晚疫病的研究进展与综合防治

马铃薯是世界第四大粮食作物,也是中国的重要粮、菜作物。马铃薯晚疫病是马铃薯的一种毁灭性病害,中国从20世纪80年代起,晚疫病的流行频率和流行程度逐渐加重,成为马铃薯生产的1个重要障碍。 中国南方雨量大,雨季长,晚疫病流行频率高而严重。北方年降雨总量较小,但是雨季集中在7、8月,正值马铃薯的结薯期,一旦流行,减产仍很严重。加之,北方的许多马铃薯产区是全国的种薯基地,晚疫病流行不仅严重降低产量,而且由于种薯带菌率高,也成为用种地     

农业部印发关于加强马铃薯晚疫病防控工作的紧急通知

晚疫病是影响马铃薯安全生产的恶性病害,一旦暴发流行,产量损失严重。入汛以来,西北、东北秋马铃薯产区雨水充沛,利于马铃薯晚疫病流行为害。据全国农作物重大病虫     

不同药剂组合对早熟马铃薯晚疫病的防治效果研究

为筛选出防治马铃薯晚疫病的新型药剂组合,有效控制和减轻马铃薯晚疫病的为害,提高马铃薯产量和质量,选择5个组合药剂开展马铃薯晚疫病防效试验.结果表明,5个不同药剂组合可有效预防和防治马铃薯晚疫病的发生和流行,防效达75.3%～86.3%,且对马铃薯安全无药害,可在今后马铃薯晚疫病预防和防治中应用.     

黔东南州马铃薯晚疫病流行因素研究

根据黔东南州近年来16个县市马铃薯晚疫病资料进行统计分析,总结探索黔东南州马铃薯晚疫病流行因素主要有气候条件适宜、品种抗性差等,为马铃薯晚疫病的预测预报及防治提供参考。     

南安市冬种马铃薯晚疫病发生规律及防治对策

对南安市冬种马铃薯晚疫病的发生情况、为害症状和发生流行因素进行分析．提出了防治马铃薯晚疫病的对策。     

马铃薯晚疫病的发生与综合治理

马铃薯是山西省北中部的主要农作物之一,晚疫病是马铃薯生产上的一种历史性、流行性病害.近年来,马铃薯晚疫病在忻州市的大发生频率增加,病害流行面积增大,对马铃薯产量和品质构成威胁.     

青海省利用马铃薯抗晚疫病品种问题的商榷

青海省是我国马铃薯的重要产区之一。晚疫病在本省容易发病的地区最近十年中流行了五次(1954、1955、1958、1959、1961年)平均每两年流行一次,一般减产在20％左右。但也有经常不流行的地区可以被利用为免疫品种繁育的基地。 1.晚疫病在青海不同地区的流行规律: 晚疫病的流行与否,完全决定于当年的气候条件。由于青海省地形复杂,各地的发病条件也不一致。根据影响晚疫病流行的两大主要气候因素——相对湿度和温度,大致可以分为三类地区: 第一类地区为温度能经常满足病害流行要求。如东部农业区的川水和部分浅山地区(海拔     

68．75％银法利SC防治马铃薯晚疫病试验

马铃薯晚疫病是一种由真菌Phytophthora infestans（Mont.）de Bary侵染马铃薯引起的毁灭性病害,是马铃薯最严重的病害之一。马铃薯晚疫病在贵州省马铃薯种植地区均有发生,在多雨、气候冷湿、适于疫病发生和流行的地区和年份,发生较重,受害马铃薯提前枯死,一般减产20％～40％。为了寻找防治马铃薯晚疫病的高效低毒药剂。     

69%WP烯酰·锰锌防治马铃薯晚疫病研究

正马铃薯晚疫病具有流行广、发病普遍的特点,且直接影响马铃薯的产量及品质。为了找到更好的防治马铃薯晚疫病的药剂及方法,我们针对69%WP烯酰·锰锌对马铃薯晚疫病的药效研究以及和几种常用防治马铃薯晚疫病的药剂进行药效的对比研究,最终对防治效果最好的药剂进行推广应用。1试验材料与方法2.1试验材料(药剂)     

寒地水稻主栽品种稻瘟病流行规律

稻瘟病是危害我国水稻生产的四大主要病害之一。在自然发病条件下,研究了黑龙江省抗、感不同和熟期不同的6个生产主栽品种稻瘟病的流行规律,分析空气温度、相对湿度、降雨量、雨日数以及初始发病率等多种流行因素对发病率的影响。结果表明,不同熟期品种,感病品种叶瘟及穗颈瘟发病时间早、发展速度快、发病程度高,发病时间比抗病品种早7～10 d,供试品种田间稻瘟病的流行规律可用Logistic模型描述。分别建立了不同抗、感品种的稻瘟病叶瘟和穗颈瘟的预测模型,其中在黑龙江省水稻生产季节雨日和相对湿度对田间稻瘟病的流行速度影响最大,是稻瘟病流行的限制因子。     

Effects of air temperature,relative humidity and canopy wetness on gray mold of cucumbers in unheated greenhouses

Microclimatic variables were monitored in cucumber crops grown in polyethylene-covered, unheated greenhouses in Israel during the winter of 1987/88. The winter was characterized by a relatively large number of rainy days. The relative humidity (RH) in the greenhouses was high (>97%) during most of the day, resulting in long periods of dew persistence. Dew point temperature and duration of dew deposition were calculated for the plant canopy. Disease incidence was monitored in 2-m-high plants, both on senescing female flowers (‘fruits’) and on stems. Multiple linear correlations were calculated for gray mold incidence and duration of air temperature and RH at specific ranges, and of leaf wetness (LW). Disease was characterized by two stages, according to the rate of its development and the microclimatic conditions influencing it. In the first phase of the epidemic a high correlation was found between infected fruits and air temperature in the range of 11–25°C, and RH in the range of 97–100% or LW. In the second phase, disease incidence was better correlated with air temperature in the range of 11–16°C and RH above 85% (R² = 0.681); there was no correlation between disease and LW at this stage. Development of stem infections was correlated with air temperature in the range of 11–16°C during the first phase of the epidemic. By contrast, the second phase was characterized by a close correlation between stem infections and RH in the range of 80–100% but also with air temperature in the range of 11–16°C, or with air temperature in the range of 11–25°C and RH 80–100%, and LW.     

Studies of a wilt disease of the potato plant in Israel caused by Erwinia chrysanthemi

In Israel field infections of potato plants by Erwinia chrysanthemi are characterized by wilting of the leaves followed by total desiccation of the plants. These symptoms are indistinguishable from those caused by Verticillium dahliae or those that develop during the normal process of plant senescence. Diagnosis of E. chrysanthemi in the spring-sown (February) crop in Israel is difficult because all three conditions often appear at approximately the same time, late in the growing season in May when the air temperature exceeds 25°C. The symptoms of E. chrysanthemi infection were reproduced in the field when potato seed tubers, tested and found to be contaminated at a low level with E. carotovora pv. carotovora , were inoculated with a strain of E. chrysanthemi isolated from a diseased potato plant. When plants in a growth cabinet at 30°C were stem-inoculated with E. chrysanthemi , similar symptoms developed when the relative humidity was low ( c . 80%). Presence of the disease only on plants grown from seed contaminated with E. chrysanthemi and not from uncontaminated seed suggests that the bacterium is seed borne, as is E. carotovora pv. atroseptica , the blackleg pathogen.     

生长季马铃薯植株冠层空气中Alternaria solani分生孢子飞散动态及其影响因素

 对生长季马铃薯冠层空气中Aternaria solani (Ell. & G. Martin ) 分生孢子的数量和马铃薯早疫病发生程度进行了系统调查,并对空气中分生孢子数量与早疫病发生程度之间的相关性以及影响空气中分生孢子数量的因素进行了分析。结果表明:在马铃薯出苗至收获(6~8月份)期间,当病情指数低于4时两者之间呈显著线性相关关系,随着病情指数的增高二者的线性相关性降低。天气条件对空气中A. solani 分生孢子数量的影响明显,通常降雨2 d后空气中孢子的数量会有一个高峰,日平均气温(地上2 m)低于18℃的条件下,空气中孢子数量会显著减少。一天中6∶00 am至16∶00 pm空气中A. solani分生孢子数量较多,17∶00 pm至次日5∶00 am孢子数量较少,分别占全天总量的 60.95%和 39.05%,各小时孢子飞散量占全天比例与空气相对湿度呈显著负相关,而与空气温度呈显著正相关。     

宁夏枸杞炭疽病发生流行的气象条件分析

根据宁夏枸杞主产区中宁县和银川市芦花台园林试验场2000～2004年不同批次的成熟枸杞果实炭疽病病情指数和气象资料,运用主成分分析结合逐步回归方法,分析了宁夏枸杞炭疽病爆发流行的主要气象因子及其影响.结果表明:影响炭疽病发生的气象因子主要是温度和空气相对湿度,其次是风力和降水.在一定温度范围内,温度越高,对炭疽病的发生越不利;空气湿度越大,越有利于枸杞炭疽病的发生.     

河南小麦叶枯类病害春季流行的时间动态规律研究

1997～1998年的研究结果表明:小麦叶枯病害在河南麦田春季的流行曲线基本呈S型曲线。始发期一般在3月20日～4月10日,指数增长期大约10～20d,该期流行速率最高;4月10～20日以后该病进入逻辑斯蒂增长期,可持续30～40d,流行速率比指数增长期稍低,没有明显的衰退期;影响小麦叶枯类病害始发期的气象因子为3月份的日照、降水量和气温,4月份的气温、日照、降水日数、相对湿度与发生程度关系密切。河南主栽小麦品种中没有对叶枯类病害免疫的品种,70%以上的主栽小麦品种为感叶枯病品种。     

An analysis of the effects of environmental factors on conidial dispersal of Uncinula necator (grape powdery mildew) in vineyards

Aerial spore concentration of Uncinula necator (the causal agent of grape powdery mildew), weather data and cropping practices were monitored during two consecutive seasons in two vineyards of the Bordeaux area. During days with no rain, spore dispersal was mainly diurnal and showed variations that followed the same pattern as that of wind speed, and a reverse pattern to that of relative humidity. Light falls of rain, of approximately 2 mm, coincided with increased spore densities in the air. Pesticide sprays using high pressure equipment generated high wind speeds at the canopy level. This may trigger high spore dispersal. High conidial stocks were produced under spontaneous conditions in the canopy. These stocks were released only under particular events, such as heavy rains, or pesticide applications with high pressure sprayers. Other cropping practices causing leaf shaking, such as pruning, may enhance spore dispersal. Over the observation period, the onset of spore dispersal was observed during a period with no rain following a rainy period, suggesting the detrimental effect of rains on epidemic onset. Epidemiological and disease management implications are discussed.     

Effects of variability in landscape types on the microclimate across a desert–oasis region on the southern margins of the Tarim Basin,China

Microclimates play important roles in controlling water budgets and water vapor transportation, as well as vegetation growth characteristics. In order to understand the differences in meteorological parameters under different vegetation cover (VC) and terrain conditions, wind velocity, air temperature, relative humidity (RH), photosynthetically active radiation (PAR), and solar radiation were simultaneously monitored on shifting, semi-fixed and fixed sandy lands, and an oasis. The air temperature and RH differences among the four landscape types were obvious in the period from May to October. It was found that the higher elevations of semi-fixed sandy land can influence PAR and solar radiation during sand-blowing weather. The differences of air temperature and RH among the four sites during the dust-storm and rainy days were not obvious, but their differences during sand-blowing weather were greater than during rainy weather and less than during floating-dust and sunny weather. The differences of PAR and solar radiation among the four landscape types were most obvious during the dust-storm event. During most of the weather types studied, significant positive correlations were found between wind velocity and temperature, PAR, and solar radiation, as well as between temperature and PAR, and solar radiation. Meanwhile, significant negative correlations were found between RH and wind velocity, temperature, PAR, and solar radiation. VC and topography were found to be the main factors influencing the changes in meteorological parameters between desert–oasis ecotone and oasis.     

新疆策勒绿洲-沙漠过渡带风、温、湿相关性分析

为研究绿洲与沙漠间水、气、热量运移规律,运用统计法、相关分析法等,选取策勒绿洲-沙漠过渡带4个不同下垫面风速(V)、气温(T)、大气相对湿度(RH)、光合有效辐射(PAR)、太阳辐射(SR)等气象要素进行相关性分析。结果表明:一天当中,起沙风发生在14:00—16:00的频率最大,且从早到晚呈现先上升再下降的趋势,与气温的日变化趋势基本一致。一年中,流沙地月平均风速与月平均气温的变化同步。从流沙地到绿洲内部,月平均风速的变化趋势明显减弱,气温的减弱趋势较小,大气相对湿度有一定增加的趋势。流沙地的月平均风速、温度呈较好的正相关性,一天中0.5 m与2 m高度之间气温、湿度差的负相关性较好。在6种天气类型中,4个下垫面每2个气象要素之间都在0.01水平上呈显著相关,阴雨天不同高度的风速与部分气象要素之间相关性不显著,流沙地在扬沙天气下、半固定沙地在浮沉天气下、固定沙地在阴雨天天气下,0.5 m高度的风速和PAR、SR均不呈显著相关性。     

水稻白叶枯病发生流行预测的研究

 作者应用多重回归法和噬菌体技术对水稻白叶枯病的发生流行趋势的预测作了研究。结果表明:(1)根据始病前两旬降水量≥ 0.1毫米日数和越冬期(12月至2月)三个月的日平均气温,可以预测田间始病期,(2)在水稻生育期内测定稻田水中噬菌体量,并根据病害流行前两旬连续三次测定噬菌体累计量、降水量和降水量≥ 10毫米日数等可预测水稻后期病害的流行趋势。同时分析了影响病害流行的主导因素(降水量≥ 10毫米日数和噬菌体量)及建立了多重回归预测模式。