几种复配杀菌剂对小麦赤霉病及DON毒素污染控制作用

为了筛选防治小麦赤霉病和控制毒素的高效杀菌剂,通过田间小区药效试验及小麦样品DON毒素检测,研究了4种杀菌剂对小麦赤霉病的防治效果和控制毒素的能力。结果表明,36%克菌丹·叶菌唑SC、45%戊唑醇·咪鲜胺EW、48%氰稀·戊唑醇SC和40%戊唑·多菌灵SC在小麦抽穗80%,扬花初期施用,对小麦赤霉病均有较好的防治效果,病指防效在84.25%~93.96%,样品DON毒素检测结果在0.12~0.64μg/ml,其中36%克菌丹·叶菌唑SC 900 ml/hm2的病指防效为93.96%,样品平均DON毒素检测结果为0.12μg/ml,控制毒素效果达93.72%。     

6种药剂对烟草赤星病的防治效果

[目的]筛选对烟草赤星病具有较好防治效果的药剂。[方法]通过大田试验研究了6种药剂对烟草赤星病的防治效果。[结果]40%菌核净、45%金叶舒菌核.琥铜、40%赤斑特WP 3种药剂对烟草赤星病的防治效果较好,分别达到76.29%、74.12%和76.80%;其次是东旺赤清,平均防效为62.11%;世高和3%多抗霉素WP的平均防效较差,分别为57.29%和58.37%。[结论]40%菌核净、45%金叶舒菌核.琥铜、40%赤斑特WP 3种药剂可因地制宜地推广应用。     

大麦云纹斑病菌中抗多菌灵乙霉威株系及其抗药性对致病性作用的分子分析

 田间抗性监测发现了大麦云纹斑病菌新型的抗性菌株,这类菌株对苯并咪唑类(多菌灵)、Phenylcarbamate(乙霉威)及三唑类(三唑醇)表现多重抗性,先前发现的多菌灵抗药性菌株均是在β-维管蛋白基因的198位点出现等位基因的突变,而新发现的菌株则仅在200位点(TTC)由苯并氨酸转变成赖氨酸(TAC)而导致对3种药剂的抗性。温室试验证明,这类菌株的致病性和野生敏感菌的致病性几乎一致,说明大麦云纹斑病菌对杀菌剂抗药性的发展与致病性之间没有相关性。     

天津地区苹果枝干病原菌优势种群分析及苹果轮纹病室内药剂筛选

对天津地区苹果枝干病原菌的主要种群进行了初步调查。６个不同地点果园主要真菌类群有：大茎点属Ｍａｃｒｏｐｈｏｍａ、球壳孢属Ｓｐｈａｅｒｏｐｓｉｓ、葡萄座腔菌属Ｂｏｔｒｙｏｓｐｈａｅｒｉａ、单隔孢属Ｂｏｔｒｙｏｄｉｐｌｏｄｉａ、壳囊孢属Ｃｙｔｏｓｐｏｒａ等，且以Ｍａｃｒｏｐｈｏｍａ出现的频率最高。经对苹果轮纹病室内药剂筛选结果分析，美国杜邦公司生产的福星杀菌剂抑菌效果最优，其次为轮纹特、甲基保果安、退菌特、福美双、代森锰锌、大生多菌灵等药剂。同时发现，大茎点菌对甲托、百菌清已产生了一定程度的抗药性。     

设施农业生产常用农药对熊蜂的毒性

用触杀和残毒试验的方法,测定了设施农业生产中常用的8种杀菌剂和5种杀虫剂对熊蜂的毒性。触杀试验表明,8种设施栽培常用杀菌剂在常规使用浓度下对熊蜂具有轻微毒性,但其致死作用很小;参试5种杀虫剂对熊蜂的毒害比较明显。     

桉树青枯病的化学防治研究

采用含毒介质法测定11种化学药剂对桉树青枯菌的抑制作用,其中,百菌清抑菌效果最好,其次为绿乳铜和世高。用百菌清和世高预先处理尾巨桉196幼苗2h后接种青枯菌,结果表明,经室内毒力测定有效的杀菌剂在预防桉树青枯病方面的作用效果非常小。     

叶菌唑与氟唑菌酰羟胺对小麦赤霉病的复配增效研究

为探索叶菌唑与氟唑菌酰羟胺复配对小麦赤霉病菌的增效作用,采用菌丝生长速率法对两种原药进行室内联合毒力测定。结果显示叶菌唑与氟唑菌酰羟胺质量比为1.5∶1时,增效系数最大。在此基础上进行田间药效试验,结果表明8%叶菌唑悬浮剂70 g/667m²+18%氟唑菌酰羟胺悬浮剂20.7 g/667m²处理的效果最好,防效为83.57%,其次为8%叶菌唑悬浮剂55 g/667m²+18%氟唑菌酰羟胺悬浮剂16.3g/667m²,防效达到78.01%。复配处理中高剂量的防效均显著高于两种单剂的推荐剂量,且试验期间没有对非靶标生物产生影响,建议在生产中使用该剂量。     

Evaluation of fungicides to control circular leaf spot of persimmon caused by Mycosphaerella nawae

The efficacy of ten fungicides against Mycosphaerella nawae, the causal agent of circular leaf spot (CLS) of persimmon, was evaluated in vitro and in field experiments. Field trials were conducted in 2009 and 2010 to investigate the comparative efficacy of the fungicides alone or combined using alternating sequences in spray programmes based on two, three or four applications. Disease incidence was assessed by estimating the percentage of affected leaves, which included leaves showing at least one necrotic spot and defoliation. Fenpropimorph, pyraclostrobin, tebuconazole and thiophanate-methyl were the most effective fungicides in inhibiting mycelial growth of M. nawae isolates (EC₅₀ < 2 ppm). In field experiments, the most effective fungicides using two spray applications were captan, chlorothalonil, mancozeb and pyraclostrobin which significantly reduced disease incidence compared with untreated plots. Regarding the number of spray applications, two applications of captan and mancozeb were less efficient than three to control the disease. However, the percentage of affected leaves provided by three applications of captan and mancozeb alone or combined with pyraclostrobin using alternating sequences in spray programmes, was not significantly different from that provided by four applications. Experimental results demonstrated that spray programmes based on three applications of these fungicides could effectively control CLS of persimmon. The advantages of spray programmes based on alternated use of strobilurins and protective fungicides are discussed.     

燕麦散黑穗病防治药剂筛选及其对燕麦幼苗生长的影响

为更好的防治燕麦(Avena sativa)散黑穗病(Ustilago avenae),筛选可行杀菌剂并测定其对病原冬孢子萌发及燕麦幼苗生长的影响,采用水琼脂平板培养冬孢子萌发法和培养皿滤纸发芽法测定5 种杀菌剂对散黑穗病菌冬孢子萌发影响以及药剂拌种对燕麦种子发芽、干物质重、根系性状的影响。结果表明:33.5%喹啉铜悬浮剂对燕麦散黑穗病病原菌冬孢子萌发抑制率为100%,且对种子发芽、干物质积累、根系生长具有促进作用;45%咪鲜胺水乳剂对燕麦散黑穗病病原菌冬孢子萌发抑制率为100%,但其拌种的燕麦种子发芽、干物质积累、根系性状均低于对照;25%嘧菌酯悬浮液、40%氟硅唑乳油、25%苯醚甲环唑乳油对燕麦散黑穗病冬孢子萌发均具有较高抑制作用,且对燕麦种子发芽、干物质积累和根系性状均无影响,其施药剂量分别为75 g·hm^-2,60 g·hm^-2和1000倍液。     

杀菌剂拌种对棉子活力影响的研究

杀菌剂拌种有助于提高棉子活力,加速棉子干物质的转化,降低病情指数,提高防治效果,显著改善棉苗素质。综合各项指标对棉子活力提高作用大小的处理依次是,代森锰锌闷种１２ｈ〉福美双闷种１２ｈ〉灵福闷种８ｈ〉多菌灵闷种８ｈ。