防治马铃薯晚疫病药剂筛选试验

选用3种药剂配方对马铃薯晚疫病进行防治试验,结果表明:施药3次,每次间隔7d,以喷施90%硫酸铜100倍液,72.2%霜霉威AS 800倍,72%霜脲.锰锌WP 600倍液轮换使用效果最佳,防效达89.0%,增产率达50.5%。     

Evaluation and analysis of reduction of late blight disease in a diploid potato progeny

The rate of late blight disease was analysed for individuals of a diploid Solanum phureja – Solanum tuberosum dihaploid hybrid population (PD), using three different assessment techniques, in the laboratory, screenhouse, and field. These hybrids expressed low disease rates in the field, comparable to resistance based on intact R genes. However, none of the parents of PD expressed any R genes and the pattern of segregation within the PD population was not indicative of R-gene inheritance. The foliage (or leaflet) area diseased had the largest broad-sense heritability of all criteria analysed, in all tests performed. In the field evaluations, the PD population showed intermediate levels of broad-sense heritability for foliage area diseased, relative to the much larger heritability detected for the group of controls possessing R genes. Resistance in the field of the PD hybrids had very little genotype-environment (G × E) interaction, indicating stability of its expression. All genotypes without R genes exhibited heritable, reduced rates of late blight disease in the field, but they were susceptible with low heritability in screenhouse and laboratory tests. This differential expression of disease indicates that the plants' indirect response to unknown environmental stress in the field may have been measured. The value of the PD hybrids for breeding of late blight resistant potato and the use of the disease rate data for detection of the underlying quantitative trait loci are discussed.     

马铃薯晚疫病的研究现状及控制策略的思考

综述了近年国内对马铃薯晚疫病的病原、发病规律、抗病育种、防治技术等的研究现状,并从疫情的监测、培育抗病品种、化学药剂的使用等方面对防控策略的研究进行了思考.     

氟噻唑吡乙酮对马铃薯晚疫病最低有效防控剂量的研究

由真菌致病疫霉Phytophthora infestans (Mont.) de Bary引起的晚疫病是马铃薯的毁灭性病害。为使新型优异杀菌剂10%氟噻唑吡乙酮可分散油悬浮剂发挥更好的作用,于2018—2019年开展了该药剂防治马铃薯晚疫病的最低有效防控剂量 (防治效果等于大于80%对应的施药剂量) 田间试验。结果表明:10%氟噻唑吡乙酮可分散油悬浮剂按有效成分9.75~14.6 g/hm2处理,于第二次施药后14 d防治效果达80%以上,此剂量即为最低有效防控剂量,比农药登记推荐低剂量少用药50.0%~25.0%。结果可为农药减施和精准施药提供依据。     

Development of potato late blight epidemics: disease foci, disease gradients, and infection sources

ABSTRACT Natural potato late blight epidemics were studied to assess the relative impact of various inoculum sources of Phytophthora infestans in Southern Flevoland (the Netherlands) from 1994 through 1996. Disease surveys were combined with characterization of isolates for mating type and DNA fingerprint pattern using probe RG57. Seventy-four percent of the commercial potato fields with early foci were clearly associated with nearby infested refuse piles. Characterization of isolates from refuse piles and fields confirmed the association. Infected seed tubers, volunteer plants, and infested allotment gardens appeared to be of minor importance for late blight development in potato fields. Several foci in refuse piles, potato fields, and allotment gardens contained more than one genotype. Due to favorable weather in August 1994, infested organic potato fields became major inoculum sources, resulting in the spread of P. infestans to adjacent conventional potato fields. Analyses of disease gradients, both at the field and regional levels, confirmed the role of the organic fields as mid-season infection sources. The mean slope of field gradients downwind of refuse piles (point sources) was significantly steeper (100-fold difference) than the mean slope of field gradients downwind of organic fields (area sources). The genotypic composition of the P. infestans populations along the gradient and of the source populations in the organic potato crops did not differ significantly. Analysis of the region gradient revealed genotype-specific disease gradients. Control measures are recommended.     

不同药剂对马铃薯晚疫病的防治效果

试验研究了68.75%氟菌.霜霉威悬浮剂、69%烯酰.锰锌可湿性粉剂、52.5%噁酮.霜脲氰水分散粒剂等8种药剂对马铃薯晚疫病的防治作用,通过差异显著性分析及灰色关联度分析得知:52.5%噁酮.霜脲氰水分散粒剂对马铃薯晚疫病的防治效果最佳,其他依次为69%烯酰.锰锌可湿性粉剂、72%霜脲.锰锌可湿性粉剂、68.75%氟菌.霜霉威悬浮剂、70%丙森锌可湿性粉剂、250g/L嘧菌酯悬浮剂、25%甲霜灵.霜脲氰可湿性粉剂、25%丁吡吗啉悬浮剂。     

Control of potato late blight using controlled-release granules containing ofurace

In an attempt to reduce or eliminate the need for spraying to control potato late blight caused by Phytophthora infestans, investigations were made on the use of controlled-release granules containing the systemic fungicide ofurace. The granules when mixed with sand and buried in soil released the fungitoxicant for about 100 days. When the granules were applied in furrows at planting, protection of potato plants (cv. Maris Bard), assessed by inoculation of detached leaflets with P. infestans, lasted for between 85 and 100 days. Application of the granules when the plants were earthed up 48 days after planting did not result in better late-season protection, possibly due to poorer uptake of the fungitoxicant by the plants at this time. Chemical analysis of leaves from plants that had received in-furrow treatment indicated that ofurace at 0.2–0.5 μg g^?1 fresh weight was needed to confer protection from late blight.     

Toxicity of propamocarb to the late blight fungus on potato

Propamocarb (Previcur-N; propyl-[3-dimethylamino-propyl] carbamate-monohydrochloride) was testedin vivo against 32 field isolates ofPhytophthora infestans from six countries. Fungicide dosages required to achieve 90% control of the blight ranged between 676 and 1530 ppm a.i. in potted potato (cv. ‘Alpha’) plants and between 1135 and 2648 ppm in potato tuber slices. Isolates from Israel were less sensitive to the fungicide than isolates from Europe or North America. Toxicity of propamocarb was not related to resistance or sensitivity to phenylamide fungicides (e.g. metalaxyl). Nevertheless, most metalaxyl-resistant isolates from Israel were less sensitive to propamocarb than most metalaxyl-sensitive isolates from this country. Monocyclic epidemics conducted with the 20 Israeli isolates in the field showed that 1081–2012 ppm of the fungicide was required to achieve 90% control of the disease. Laboratory experiments revealed that the fungicide was poorly active against sporangial germination and had a limited curative efficacy. It exhibited a translaminar translocation in leaves but a poor acropetal or basipetal systemicity from foliage. Propamocarb + mancozeb mixtures (1:1, v/w) were synergistically effective in controlling the blight. Growers in Israel use tank mixtures of propamocarb (Dynone) and mancozeb to combat late blight in potato fields where phenylamide-resistant isolates ofP. infestans are prevalent.     

几种杀菌剂对冬种马铃薯晚疫病的防治效果

试验结果表明:每亩用72%霜脲氰·锰锌SG100g+68.75%氟吡菌胺·霜霉威盐酸盐SC75ml、72%霜脲氰·锰锌SG100g、68.75%氟吡菌胺·霜霉威盐酸盐SC75ml和58%甲霜灵锰锌WP100g对冬种马铃薯晚疫病均有较好的防治效果,其中以每亩用72%霜脲氰·锰锌SG100g+68.75%氟吡菌胺·霜霉威盐...     

十一种杀菌剂防治马铃薯晚疫病的适宜施用时期

为了明确当前市场上具有代表性的11种防治马铃薯晚疫病杀菌剂的适宜施用时期,采用人工接种马铃薯叶片的方法,测定了其中5种药剂在接种晚疫病菌前10 d内不同时间施用的预防效果和其中7种药剂在接种后24 h内不同时间施用的治疗效果。结果显示:在保证良好防治效果的前提下,药剂在病原菌接种前保护性施用的适宜时期比在接种后治疗性施用的适宜时期要长。在测试浓度下,接种前5种供试药剂保持100%防治效果的适宜施用时期为接种前3~10 d;而接种后7种供试药剂保持相同防效的适宜施用时期仅为接种后6~12 h,在生产实际中难以操作。研究结果说明,在田间马铃薯晚疫病的化学防治中,为了取得良好防治效果,每次用药均应在病菌侵入之前采用保护性施用,尽量避免在病菌侵入之后进行治疗性施用。     

马铃薯晚疫病预测模型与预警技术研究进展

介绍了马铃薯晚疫病11个预测模型和6个电脑化模型;描述了模型预测的判断标准和预警指标,并作了评价提出存在问题;讨论了建立网络化病害预测模型和实现自动预警配套技术;报道了2003年直接应用于田间马铃薯晚疫病监测技术。     

热处理种薯防治马铃薯晚疫病试验

马铃薯晚疫病在张家口一带,初侵染的主要来源是,由于播种了带菌病薯。为此,我们曾试用药剂、温水、干热等方法处理种薯,消灭病菌,结果以温水处理种薯效果最好。试验材料是本地感病品种“紫山药”,感病程度严重,病斑占薯面1/3到1/2。     

马铃薯晚疫病菌分子遗传及与寄主互作研究

近年来马铃薯晚疫病的重新暴发再次引起世界各国极大关注,特别对马铃薯晚疫病菌的分子遗传学的研究,包括病菌基因组遗传、转录和物理图谱的构建,病菌致病的分子机制以及马铃薯-马铃薯晚疫病菌互作分子机制等。本文就近几十年来对马铃薯晚疫病菌在生物学和病理学,分子遗传学等研究方面作简要综述,并对其研究趋势进行了展望。     

Control of potato late blight (Phytophthora infestans) with systemic fungicides

A mixture (‘Fubol’) of metalaxyl with mancozeb, performed better than mixtures of propamocarb (as the hydrochloride) or the experimental fungicide cymoxanil with mancozeb, when applied as sprays to control potato blight in a small-scale field trial conducted in 1978. Another experimental fungicide, 2-chloro-N-(2-oxotetrahydrofuran-3-yl)acet-2″,6′-xylidide (RE 20615), applied at a greater rate but without mancozeb, was as effective as ‘Fubol’. The mixture of mancozeb and propamocarb or cymoxanil performed no better than mancozeb alone. In 1979, when blight incidence was greater, use of RE 20615/dithiocarbamate mixtures allowed the extension of spray intervals to 21 days, compared with a 14-day schedule for the dithiocarbamate alone. RE 20615, applied in 1979 to the soil within the furrows at planting time as a controlled-release granular formulation, gave adequate control of late blight up to early September, after which disease development accelerated. Yield was not significantly different from that obtained with a standard dithiocarbamate treatment.     

马铃薯晚疫病CARAH预警模型在我国的应用及评价

CARAH预警模型引入我国后,在马铃薯晚疫病监测预警中发挥了重要作用。本文对目前各地CARAH模型的应用情况进行了综合分析,总结了模型在马铃薯晚疫病中心病株出现时间预测、发生程度风险评估、防治效果等方面的作用,分析了品种抗性、区域气候特征等因素对模型应用的影响,提出了进一步研究和完善建议。     

近几年我国马铃薯晚疫病流行特点分析与监测建议

马铃薯晚疫病是马铃薯上的重要病害,是影响马铃薯产业发展的主要制约因素。本文系统总结了2008-2014年我国马铃薯晚疫病的发生概况及特点,分析了其影响因素。该病害年度间、地区间、品种间发生不平衡,北方产区受气候因素影响大,西南及中原产区常年偏重发生。2012年、2013年马铃薯晚疫病在全国范围内偏重发生,局部大发生,发生范围广、流行扩展速度快、危害重。在气候、菌源量、品种抗性及防治因素中,气候是影响马铃薯晚疫病发生流行的最重要因素。     

Control of late blight in potato by full and reduced rates of oxadixyl mixtures

The effect of oxadixyl-based fungicidal mixtures on the development of late blight and the buildup of resistance ofPhytophthora infestans to oxadixyl was studied in potato crops (cv. Alpha) grown in plastic houses. Half-rates of SAN 518F (mancozeb + oxadixyl) applied weekly provided better disease control and reduced resistance buildup more effectively than the full rates of the mixture applied biweekly. Mancozeb applied weekly at full rate was less effective than SAN 518F at half-rate. The data suggest that lowering the dosage together with shortening the interval between sprays is an efficient strategy to combat mixed populations — sensitive and resistant to phenylamides — ofP. infestans when phenylamide-based fungicidal sprays are used.     

Assessment of the impact of mid-season late blight infection on disease development and yield of potato variety Russet Norkotah in Maine

Development of late blight of potatoes caused by Phytophthora infestans (US 8 fungal genotype, A2 mating type) was monitored in two Russet Norkotah commercial fields at Fort Fairfield in 1996 and Duncan Farm in 1997. Experimental plots representing various disease treatments (low, moderate, high and random late blight severity levels) were established in two fields in 1996. In 1997, only low and high disease treatments were established. The application of fungicides for late blight control was conducted in both years. Late blight incidence and severity were assessed in each plot of each treatment. Components of late blight disease development, tuber blight incidence and tuber yields were determined from each plot. Progress of late blight disease was rapid in 1996 but not in 1997. During the 1996 cropping season, mean disease incidence and severity in the random disease treatment plots were 84 and 21% respectively within 10 days of disease detection. In 1997, low levels of late blight severity were detected in the field plots. Average numbers of late blight leaf and stem lesions on infected plant and fungal sporangia on the diseased leaf were not significantly affected by disease treatment. Late blight foliar severity significantly affected potato tuber yields. Lowest tuber yield was obtained in plots with high disease levels and highest yields were recorded in plots with low late blight severity in 1996. Late blight severity was significantly correlated with tuber yield but not with per cent tuber blight.