高密度栽培条件下玉米纹枯病的发生与防治

采用田间小区试验,以50%多菌灵可湿性粉为防治药剂,进行不同防治时期、次数和其他处理,研究其对玉米纹枯病的防治效果。防治效果最好的为拔节期摘除病叶鞘并施药,其次为拔节期剥病叶鞘不施药,最差的是灌浆期施药。防治的适期应掌握在拔节期,摘除病叶鞘并施药。     

拿敌稳防治水稻稻瘟病和纹枯病示范总结

在水稻孕穗期和齐穗期喷施拿敌稳,末次施药后7 d对病害发生情况进行调查,结果显示:田间未发生穗颈瘟;纹枯病调查:喷洒拿敌稳处理纹枯病病鞘率2.0%,病情指数0.3%,防治效果92.8%。末次施药后14 d对病害发生情况进行调查,结果显示:喷洒拿敌稳处理穗颈瘟田间病穗率0.9%,病情指数0.1%,防治效果50%;纹枯病病鞘率9.6%,病情指数4.0%,防治效果74.0%;各处理中,喷施拿敌稳处理,理论产量最高673.9 kg/667 m2,比对照药剂增产2.1%,比清水对照增产4.4%;稻谷整精米率最高为69.6%,比常规对照高0.8%,比清水对照高1.2%。     

芒果炭疽病流行过程,流行成因分析及施药指标预报研究

研究结果表明,芒果炭疽病在流行过程中,流行速度有多次升降;流行曲线属多峰曲线。每次流行速度上升过程主要是按照逻辑斯蒂生长模型的规律发展,但其指数增长期不明显。当前推广的品种都较感病,感病期长,菌源多,这些都已满足病害流行之需要。病害流行强度主要决定于芒果感病期间的气候条件。温暖高湿,连续降雨,则病害迅速发展造成流行。据此建立了施药预测指标,经３ａ应用,可减少２次喷药,并获得较好的防治效果。     

玉米纹枯病的发生与防治

介绍了玉米纹枯病的发生和危害;对玉米纹枯病的病原、病症及发病规律进行了研究分析;根据病害发病的规律及流行条件,提出了对玉米纹枯病的综合防治措施。     

寒地水稻主要病害调查研究

2008年,黑龙江省农垦科学院植物保护研究所组织水稻植保科研人员对宝泉岭、红兴隆、建三江、牡丹江、齐齐哈尔和绥化等6个分局有代表性农场进行稻瘟病、鞘腐病、纹枯病和褐变穗等病害调查,结果表明:稻瘟病和褐变穗病情指数较低,没有发现大面积严重发生稻瘟病的地块;纹枯病发生已比较普遍,各农场纹枯病发生程度有一定差异;少数农场鞘腐病发生严重,对水稻产量有一定影响。     

辽河稻区水稻纹枯病发病规律及药剂防治分析

为明确辽河稻区纹枯病的发病规律并筛选出高效低度的杀菌剂。首先本研究通过记录与统计2016年水稻生长周期中纹枯病发生的各项指标,明确纹枯病的始发时间为6月底、爆发时间7月初、稳定时间8月末直至9月底生长周期结束,为病害防控的最佳适期提供依据。其次,掌握纹枯病防治的最佳施药时间为6月底水稻分蘖盛期,并明确了5种杀菌剂均对纹枯病的防治有显著的作用。其中吡唑醚菌脂是5种药剂中防治效果最显著的,其可把病指控制在3.57左右,病害防治率可达到89.79%,水稻产量高达701.5 kg/667 m~2,具有极显著的增产作用,增产率可达28.2%,为辽河稻区水稻的田间防治提供了实践的依据。     

玉米纹枯病菌的分子检测

近年来随着气候的变化和玉米种植密度的加大,玉米纹枯病发生日益严重,该病株残体残留在田土表面土层较浅的区域进行越冬。为准确诊断玉米纹枯病,根据玉米主要病害玉米大斑病、玉米弯孢菌叶斑病、玉米灰斑病rDNA的ITS区间序列差别,设计合成1对特异性扩增引物（LZ-F+LZ-R）用于玉米纹枯病检测。该引物能从玉米纹枯病菌扩增到特异性的分子片段,说明设计的特异性引物可以用来检测玉米纹枯病菌。采集田间玉米纹枯病、玉米大斑病、玉米弯孢菌叶斑病、玉米灰斑病病株样本进行病原菌分离,同时提取其病原菌和土壤总DNA,利用上述引物进行扩增。结果表明,只有以R.solani基因组DNA为模板通过反应体系在PCR仪中进行扩增最终能扩增出1条460 bp左右清晰的特异性条带,其他菌株均无特异性条带。利用该特异性引物只能从受到该病害侵染的发病组织DNA中扩增出特异性条带,对照及健康玉米植株均无扩增条带。接种该病原菌的土壤DNA也扩增出相应的特异性条带,表明特异性引物LZ-F/LZ-R可用于玉米纹枯病菌的分子检测和早期诊断。     

不同药剂对机插水稻纹枯病的田间防效

纹枯病是水稻三大病害之一,本文进行了几种不同药剂防治机插水稻纹枯病药效的研究。试验结果表明,在机插水稻纹枯病发病初期施药,一次用药30%丙环·咪鲜胺EW 60 m L/667 m2、30%噻呋·己唑醇SC 25 m L/667 m2对机插水稻纹枯病有良好的防治效果,并且持续期达到20 d以上;40%嘧菌酯WP 15 g/667 m2、24%井冈霉素AS 30 m L/667 m2对纹枯病也有较好的效果,但二者防治效果差异不显著;15%井冈·戊唑醇SC 50 m L/667 m2、40%酚菌酮EW 80 m L/667m2、30%苯甲·丙环唑EC 20 m L/667 m2不能有效地控制纹枯病的发生。     

稻秆还田对水稻主要病害发生的影响

通过水稻秸秆还田小区试验,初步探讨了多年秸秆还田对15个水稻品种病害的影响。试验结果表明：秸秆还田的老稻田15个水稻品种的稻瘟病、鞘腐病、纹枯病的病情指数都高于对照稻田的病情指数。黑龙江省农垦总局建三江分局主栽品种空育131,叶瘟病情指数增加了2．3％,穗颈瘟增加了2．6％,鞘腐病增加了2．2％,纹枯病增加了0．4％。     

玉米纹枯病研究进展及分子标记辅助选择策略

玉米纹枯病已成为我国玉米生产上的一种严重病害,且有逐年加重的趋势。系统地介绍了玉米纹枯病的症状、病原菌、致病机理、发病规律和防治措施以及玉米纹枯病抗性遗传等方面的研究进展,并从实际出发,提出了抗玉米纹枯病育种的分子标记辅助选择策略。     

双株定向栽培模式对玉米纹枯病发生和流行影响的初步研究

根据植物病害流行学原理,通过田间试验设计及人工接种技术,对双株定向栽培模式与常规栽培模式下玉米纹枯病发生流行动态进行初步比较研究。结果表明,玉米双株定向栽培模式冠层内温湿度均低于常规栽培模式,而其玉米纹枯病发病也较轻。通过SPSS 11.5软件对比分析,Logistic模型能够用于描述双株定向栽培模式下玉米纹枯病流行时间动态。应用该模型推导病害指数增长期(始发期)双株定向栽培模式出现较晚,而Logistic增长期(盛发期)则长于常规模式。     

Development of a formulation of Pseudomonas fluorescens PfALR2 for management of rice sheath blight

Pseudomonas fluorescens isolates that inhibited growth of Rhizoctonia solani, the rice sheath blight pathogen, were isolated from the rhizosphere of different crops. One of the most effective strains, PfALR2, was developed as an antibiotic resistant strain and a peat-based formulation was developed for this bacterium. The effective dose of a peat formulation was assessed for seed treatment, root treatment, soil application and foliar spraying. All individual treatments controlled the disease effectively. However, a combination of all four treatments resulted in the best sheath blight control in the greenhouse. In field trials, application of the peat-based formulation of PfALR2 effectively controlled the disease, increased yield, and efficacy was comparable to that of the commercially available fungicide, carbendazim.     

Effects of cultivar resistance and single fungicide application on rice sheath blight, yield, and quality

The increased number of sheath blight (Rhizoctonia solani)-resistant rice (Oryza sativa) cultivars available will allow producers to use less fungicide and avoid significant reductions in grain and milling yields. Among cultivars currently in cultivation in the southern United States, sheath blight resistance levels range from very susceptible to moderately resistant. A study was conducted to determine the response of cultivars, with different levels of susceptibility, to sheath blight inoculations and fungicide application and to determine the impact of sheath blight disease development on rice yield and quality. Sheath blight epidemics in field plots were initiated by inoculation at the panicle differentiation growth stage in 2006 and 2007. Azoxystrobin at 0.17 kg a.i. ha⁻¹ was applied at mid-boot. Inoculation significantly increased sheath blight severity and incidence and caused yield losses of 8% in moderately resistant cv. Jupiter to 40% in very susceptible cv. Trenasse. Milling yields were affected to a lesser extent. Fungicide treatments reduced sheath blight incidence and severity, regardless of cultivar except in Jupiter. Single azoxystrobin applications were effective in minimizing yield loss due to sheath blight in all cultivars.     

嘧菌酯对马铃薯早疫病最低有效防控剂量的研究

由茄链格孢霉[Alternaria solani(Ell.et Mart.)Jones et Grout.]引致的马铃薯早疫病是世界马铃薯产区普遍发生的病害,喷施杀菌剂是防治马铃薯早疫病的常用手段。为探索减少杀菌剂嘧菌酯施用剂量对马铃薯早疫病防治效果,2018~2019年进行了嘧菌酯对马铃薯早疫病最低有效防控剂量的田间试验。试验在3个地理区域(乌兰察布市凉城县、临汾市蒲县、呼伦贝尔市扎兰屯市)完成,分别代表了不同气候、栽培和耕作特点。每个地点的2次施药分别在7月末和8月初进行,间隔7~10 d。250 g/L嘧菌酯悬浮剂有效剂量112.5 g/hm2处理,在第2次施药后14 d的防效达80%以上,此施药量为嘧菌酯对马铃薯早疫病最低有效防控剂量,比该农药登记推荐剂量(有效剂量150.0~187.5 g/hm²)减少用药25.00%~40.00%。研究结果可指导马铃薯早疫病防治农药减施和精准施药。     

18.7%丙环·嘧菌酯对水稻纹枯病的防治效果

2015年,在中国主要水稻种植区安徽、湖北、江苏、广东和广西等地进行18.7 %丙环·嘧菌酯的水稻纹枯病防治示范试验。结果表明,18.7 %丙环·嘧菌酯在600-750 mL/hm2使用剂量下,纹枯病发病初期(丛发病率达5 %左右)时用药1次,隔10 d再用药第2次,对纹枯病的防治效果突出,且显著优于对照,对水稻安全,具有明显的增产效果。     

Potato late blight control and top desiccation when pesticides are applied with a controlled droplet and a conventional sprayer

Disease development was observed in field plots to which two different fungicides, each at two rates, were applied regularly with either a conventional or a controlled droplet sprayer. The type of fungicide did not affect disease severity, but more disease damage occurred in the controlled droplet sprayer plots than in conventional sprayer plots. Reduced rates of fungicide resulted in higher disease incidence ratings than recommended rates of fungicides by end of the spraying season. Lower marketable tuber yields and greater incidences of late blight tuber rot were related to foliar disease levels, the different sprayer types, and rates of applied fungicide. No significant differences in terms of potato top desiccation efficacy between the two sprayer types were obtained. In addition, total tuber yield and level of vascular discoloration were similar for both the controlled droplet and conventional sprayer.     

Comparison of the NegFry decision suport system with routine fungicide application for the control of potato late blight in Ireland

Summary Field experiments between 1996 and 2000 compared the efficacy of fungicide programmes applied in accordance with the NegFry and Met éireann (Mé) decision support systems (DSS) for the control of late blight with 7- and 10-day routine fungicide programmes. The Mé DSS reduced fungicide use by 68% and 54% respectively while NegFry reduced fungicide use by 49% and 27% compared with the 7- and 10-day programmes. The NegFry DSS was similar to the 10-day routine programme in terms of late blight control, quality and marketable yield. A similar result was found when the NegFry DSS was compared with a 7-day routine mancozeb programme (included for two seasons only). Within the NegFry DSS the use of fluazinam resulted in improved yield, foliage blight and tuber blight control compared with mancozeb, but this benefit was significant for tuber blight only. The Mé DSS resulted in inferior disease control, yield and quality.     

Effects of rice-water chestnut intercropping on rice sheath blight and rice blast diseases

Both sheath blight and blast are important rice diseases worldwide. The exploration of environmentally sound practices to control these diseases will help to reduce fungicide application. Effects of rice (Oryza sativa) intercropping with water chestnut (Eleocharis dulcis) on rice sheath blight and rice blast disease as well as the extracts of different plant parts and root exudates from water chestnut on pathogens of rice sheath blight (Rhizoctonia solani) and rice blast disease (Magnaporthe oryzae) were investigated using pot experiments and bioassay tests. The results from pot tests showed that rice-water chestnut intercropping system suppressed sheath blight and blast and improved land equivalent ratio (LER). The results from bioassay tests indicated that extracts and root exudates from water chestnut had significant effects to inhibit the expansion of these pathogens. The scales of these inhibitions were time and concentration dependent. The antifungal activities of the extracts from aboveground parts and pulp of water chestnut were significantly higher than the extracts from other parts and root exudates. The water extracts of aboveground parts showed the highest antifungal activity on both pathogens according to EC₅₀ values. The antifungal activities of the same extracts from water chestnut on R. solani were significantly higher than on M. oryzae. The result suggests that water chestnut possesses bioactive substances to suppress rice sheath blight disease and rice blast disease. The rice-water chestnut intercropping system can be used as an environment-friendly method for diseases control in rice field.     

不同药剂不同施药次数防治水稻纹枯病田间药效试验

通过田间试验,比较分析了不同药剂对水稻纹枯病的防治效果。结果表明,25%嘧菌酯悬浮剂1 350 g/hm~2、24%噻呋酰胺悬浮剂345 g/hm~2、25%丙环唑乳油600 g/hm~2对水稻纹枯病的防效均在87%以上,43%戊唑醇悬浮剂的防效为74.38%;4种药剂的田间药效比生产上常用药剂井冈霉素的防效分别提高0.79倍、0.75倍、0.69倍、0.43倍,头季和再生季每hm~2综合增收6 499元、4 042元、2 051元、1 913元。从防治效果和经济效益来看,25%嘧菌酯悬浮剂、24%噻呋酰胺悬浮剂、25%丙环唑乳油均可以作为本地防治水稻纹枯病的主体药剂进行推广应用。     

8种药剂对马铃薯晚疫病的防治效果试验

为减轻马铃薯晚疫病对马铃薯生产造成的损失,本研究选择了8种药剂,在马铃薯地上垄体栽培模式下进行晚疫病防治的药效比较试验。结果表明,不同处理均对地上垄体栽培模式下马铃薯晚疫病具有防治和保产的效果。其中,在马铃薯晚疫病发病前期喷施的保护性杀菌剂种中,60%百泰的防治和保产效果最好,防效达79%以上,增产43.54%;其次是银法利,防效达70%以上,增产42.55%。在发病中期喷施的治疗性杀菌剂中,防效和保产效果最好的药剂为50%安克,防效达73%以上,增产36.71%。