Lonergan Erin, Pasche Julie, Skoglund Linnea, Burrows Mary
Plant Sciences and Plant Pathology Department, Montana State University, Bozeman 59717.
Department of Plant Pathology, North Dakota State University, Fargo 58108.
Plant Dis. 2015 Sep;99(9):1254-1260. doi: 10.1094/PDIS-06-14-0620-RE. Epub 2015 Jul 27.
Management of Ascochyta blight in pea, lentil, and chickpea relies on repeated fungicide applications, which has led to development of fungicide resistance and disease control failures in some systems. In vitro assays were conducted to determine baseline fungicide sensitivity in Mycosphaerella pinodes (Ascochyta pinodes), A. lentis, and A. rabiei populations to the demethylation-inhibiting fungicide prothioconazole and the succinate dehydrogenase-inhibiting fungicides boscalid and fluxapyroxad by determining the effective concentration at which 50% of germination or fungal growth was inhibited (EC). Mean boscalid EC values from conidial germination assays were 0.669, 0.639, and 0.171 μg/ml and from mycelial growth assays were 0.258, 0.791, and 0.443 μg/ml for M. pinodes, A. lentis, and A. rabiei, respectively. Mean fluxapyroxad EC values were 0.050, 0.763, and 0.057 μg/ml for M. pinodes, A. lentis, and A. rabiei, respectively. Mean baseline EC values for prothioconazole with mycelial growth were 0.541, 0.604, and 0.283 μg/ml for M. pinodes, A. lentis, and A. rabiei, respectively. A single discriminatory fungicide concentration of 1 μg/ml was selected for all species. Established sensitivity profiles and discriminatory concentrations will be used to monitor sensitivity shifts in populations of Ascochyta spp. and to make effective disease management recommendations.
豌豆、小扁豆和鹰嘴豆上壳二孢叶枯病的防治依赖于反复施用杀菌剂，这已导致在一些系统中出现杀菌剂抗性和病害防治失败的情况。进行了体外试验，通过确定抑制50%发芽或真菌生长的有效浓度（EC），来测定松针球腔菌（壳二孢菌）、扁豆壳二孢菌和鹰嘴豆壳二孢菌群体对脱甲基抑制剂杀菌剂丙硫菌唑以及琥珀酸脱氢酶抑制剂杀菌剂啶酰菌胺和氟唑菌酰胺的基线杀菌剂敏感性。啶酰菌胺分生孢子萌发试验的平均EC值分别为0.669、0.639和0.171μg/ml，菌丝生长试验的平均EC值分别为0.258、0.791和0.443μg/ml，对应松针球腔菌、扁豆壳二孢菌和鹰嘴豆壳二孢菌。氟唑菌酰胺的平均EC值分别为0.050、0.763和0.057μg/ml，对应松针球腔菌、扁豆壳二孢菌和鹰嘴豆壳二孢菌。丙硫菌唑菌丝生长的平均基线EC值分别为0.541、0.604和0.283μg/ml，对应松针球腔菌、扁豆壳二孢菌和鹰嘴豆壳二孢菌。为所有物种选择了1μg/ml的单一鉴别杀菌剂浓度。已建立的敏感性概况和鉴别浓度将用于监测壳二孢菌种群的敏感性变化，并提出有效的病害管理建议。
