Abstract：
Claviceps purpurea (Fr.) Tul is the causal organism for ergot impacting grass hosts, including wheat. The pathogen produces ergot alkaloids (EAs) during the development of mature sclerotia leading to potential wheat quality discounts or rejection at the point of sale. Cultural practices are recommended for the management of ergot in wheat, but there is limited information pertaining to the use of in-season fungicides to help reduce ergot. The objective of this research was to evaluate the efficacy of four fungicides (prothioconazole + metconazole, pydiflumetofen + propiconazole, azoxystrobin + propiconazole, and fluxapyroxad + pyraclostrobin) on sclerotia characteristics, and EAs associated with C. purpurea. A field experiment was established using a male-sterile hard red spring line with fungicide applications occurring at complete full head emergence (Feekes Growth Stage 10.5). Individual plots were harvested and cleaned, and ergot sclerotia were collected. Physical characteristics and toxin production were examined. Fungicides had a significant (p < .05) impact on total ergot body weight (EBW), with all fungicides having lower EBW than the nontreated control. The fungicide premixture of pydiflumetofen + propiconazole had the lowest EBW among all treatments. Fluxapyroxad + pyraclostrobin had the lowest levels of EAs among fungicides. Results suggest that fungicide premixtures can potentially reduce EBW and influence EA production in wheat.
摘要：
紫癜（Fr.)Tul是麦角影响草宿主的因果生物，包括小麦。病原体在成熟菌核的发育过程中产生麦角生物碱（EA），导致潜在的小麦质量折扣或在销售点被拒绝。建议将文化习俗用于小麦中麦角的管理，但是关于使用季节性杀菌剂来帮助减少麦角的信息有限。本研究的目的是评估四种杀菌剂（丙硫菌唑+美康唑，吡双氟美托芬+丙环唑，唑酯+丙环唑，和fluxapyroxad+pyraclostrobin)对菌核特性的影响，和与紫癜相关的EA。使用雄性不育的硬红色春季线进行了田间试验，并在完全完全出现时（Feekes生长期10.5）进行了杀菌剂的应用。个别地块被收获和清理，并收集了麦角菌核。检查了物理特性和毒素产生。杀菌剂对麦角总体重(EBW)有显著影响(p<.05)，所有杀真菌剂的EBW均低于未处理的对照。在所有处理中，吡氟美托芬丙环唑的杀菌剂预混物的EBW最低。Fluxapyroxadpyraclostrobin在杀菌剂中的EA含量最低。结果表明，杀菌剂预混物可能会降低EBW并影响小麦的EA产量。
