Tobacco black shank caused by Phytophthora parasitica var.nicotianae(Breda de Hean)is one of the most serious diseases in tobacco growing,and few effective fungicides are available currently.The purpose of this study ...Tobacco black shank caused by Phytophthora parasitica var.nicotianae(Breda de Hean)is one of the most serious diseases in tobacco growing,and few effective fungicides are available currently.The purpose of this study was to assess the feasibility of using fluazinam to treat tobacco black shank disease.In vitro toxicities of fluazinam to 62 isolates of P.nicotianae were determined by mycelial growth rate method.The EC50 values ranged from 0.294 6 to 2.389 9 μg/mL with a mean of 1.084 0 μg/mL.The sensitivity distribution was unimodal,and there was no resistant isolate in P.nicotianae population.The carboxylic acid amide(CAA)fungicides were single-site in action and activity to oomycetes.The synergistic interactions were tested by Wadley method between fluazinam and dimethomorph,flumorph,mandipropamid,respectively.The mixture containing dimethomoph:Huazinam at 1:2 ratio showed additive actions,with the synergy ratio of 1.2.The mixture containing flumorph and fluazinam at 1:5 ratio had the highest synergy ratio(SR 2.07).Mandipropamid and fluazinam had an additive interaction and the proportion of 2:1 had the lowest EC50 value(0.020 7 μg/mL).This study demonstrated the sensitivity of P.nicotianae to fluazinam,and provided the experimental foundation to use fluazinam for tobacco black shank management.展开更多
为了更好地进行烤烟质量综合评价,综合使用熵权法和改进的逼近理想解排序法(Technique for Order Preference by Similarity to Ideal Solution,TOPSIS)对114个烤烟样品的外观质量、感官质量、常规化学成分协调性进行综合评价,得到外观...为了更好地进行烤烟质量综合评价,综合使用熵权法和改进的逼近理想解排序法(Technique for Order Preference by Similarity to Ideal Solution,TOPSIS)对114个烤烟样品的外观质量、感官质量、常规化学成分协调性进行综合评价,得到外观质量接近度、感官质量接近度、化学成分接近度和综合质量接近度,并采用简单相关分析法分析烤烟综合质量指标与各质量接近度间的相关性。结果表明:①熵权法得到的外观质量、感官质量和常规化学成分在综合评价中的权重分别为0.316、0.380和0.304;②四川凉山州会理县太平镇、云南红河州弥勒市弥阳镇、云南红河州建水县临安镇、四川凉山州会理县黎溪镇和四川凉山州德昌县茨达镇生产的清甜香型烟叶质量较好;③与清甜香型烟叶综合质量呈正相关关系的指标包括:外观指标中的色度、身份、油分、颜色和叶片结构,感官指标中的干燥感、圆润感、香气量、杂气、透发性、余味、香气质、程度、刺激性、细腻程度和工业可用性,化学成分中的总植物碱和糖碱比。展开更多
文摘Tobacco black shank caused by Phytophthora parasitica var.nicotianae(Breda de Hean)is one of the most serious diseases in tobacco growing,and few effective fungicides are available currently.The purpose of this study was to assess the feasibility of using fluazinam to treat tobacco black shank disease.In vitro toxicities of fluazinam to 62 isolates of P.nicotianae were determined by mycelial growth rate method.The EC50 values ranged from 0.294 6 to 2.389 9 μg/mL with a mean of 1.084 0 μg/mL.The sensitivity distribution was unimodal,and there was no resistant isolate in P.nicotianae population.The carboxylic acid amide(CAA)fungicides were single-site in action and activity to oomycetes.The synergistic interactions were tested by Wadley method between fluazinam and dimethomorph,flumorph,mandipropamid,respectively.The mixture containing dimethomoph:Huazinam at 1:2 ratio showed additive actions,with the synergy ratio of 1.2.The mixture containing flumorph and fluazinam at 1:5 ratio had the highest synergy ratio(SR 2.07).Mandipropamid and fluazinam had an additive interaction and the proportion of 2:1 had the lowest EC50 value(0.020 7 μg/mL).This study demonstrated the sensitivity of P.nicotianae to fluazinam,and provided the experimental foundation to use fluazinam for tobacco black shank management.
文摘为了更好地进行烤烟质量综合评价,综合使用熵权法和改进的逼近理想解排序法(Technique for Order Preference by Similarity to Ideal Solution,TOPSIS)对114个烤烟样品的外观质量、感官质量、常规化学成分协调性进行综合评价,得到外观质量接近度、感官质量接近度、化学成分接近度和综合质量接近度,并采用简单相关分析法分析烤烟综合质量指标与各质量接近度间的相关性。结果表明:①熵权法得到的外观质量、感官质量和常规化学成分在综合评价中的权重分别为0.316、0.380和0.304;②四川凉山州会理县太平镇、云南红河州弥勒市弥阳镇、云南红河州建水县临安镇、四川凉山州会理县黎溪镇和四川凉山州德昌县茨达镇生产的清甜香型烟叶质量较好;③与清甜香型烟叶综合质量呈正相关关系的指标包括:外观指标中的色度、身份、油分、颜色和叶片结构,感官指标中的干燥感、圆润感、香气量、杂气、透发性、余味、香气质、程度、刺激性、细腻程度和工业可用性,化学成分中的总植物碱和糖碱比。