Genet Jean-Luc, Jaworska Grazyna
DuPont Crop Protection, European Research and Development Centre, F-68740 Nambsheim, France.
Pest Manag Sci. 2009 Aug;65(8):878-84. doi: 10.1002/ps.1768.
Proquinazid is a new quinazolinone fungicide from DuPont registered in most European countries for powdery mildew control in cereals and vines. The aim of this paper is to present baseline sensitivity data in populations of Blumeria graminis f. sp. tritici EM Marchal and Erysiphe necator (Schw) Burr as well as results from cross-resistance studies with other fungicides.
Proquinazid exhibited a high intrinsic activity on B. graminis f. sp. tritici isolates at rates ranging from 0.000078 to 0.02 mg L(-1). Erysiphe necator isolates were comparatively less sensitive to proquinazid, with EC(50) values ranging from 0.001 to 0.3 mg L(-1). Proquinazid controlled equally well B. graminis f. sp. tritici isolates sensitive and resistant or less sensitive to tebuconazole, fenpropimorph, fenpropidin, cyprodinil and kresoxim-methyl. A positive correlation (r = 0.617) between quinoxyfen and proquinazid sensitivities was found among 51 B. graminis f. sp. tritici isolates. Quinoxyfen-resistant B. graminis f. sp. tritici isolates were slightly less sensitive to proquinazid than the quinoxyfen-sensitive isolates; however, proquinazid remained much more active than quinoxyfen on these isolates. A stronger sensitivity relationship (r = 0.874) between proquinazid and quinoxyfen was found among 65 E. necator isolates tested in a leaf disc assay. The sensitivity values for proquinazid were significantly lower than those for quinoxyfen, confirming the higher intrinsic activity of proquinazid on both pathogens.
Given the history of resistance development in powdery mildew and the observed sensitivity relationship with quinoxyfen, specifically in E. necator, we conclude that the risk of resistance developing to proquinazid might be influenced by the use of quinoxyfen. Based on these results, the authors recommend that proquinazid and quinoxyfen be managed together for resistance management.
丙硫菌唑是杜邦公司研发的一种新型喹唑啉酮类杀菌剂，已在大多数欧洲国家登记用于防治谷物和葡萄上的白粉病。本文旨在提供小麦白粉病菌（Blumeria graminis f. sp. tritici EM Marchal）和葡萄白粉病菌（Erysiphe necator (Schw) Burr）群体的基线敏感性数据，以及与其他杀菌剂的交互抗性研究结果。
丙硫菌唑对小麦白粉病菌分离株表现出较高的内在活性，有效剂量范围为0.000078至0.02 mg L(-1)。葡萄白粉病菌分离株对丙硫菌唑的敏感性相对较低，其EC(50)值范围为0.001至0.3 mg L(-1)。丙硫菌唑对小麦白粉病菌中对戊唑醇、粉唑醇、氟环唑、嘧菌环胺和醚菌酯敏感、抗性或敏感性较低的分离株的防治效果相当。在51个小麦白粉病菌分离株中，喹氧灵和丙硫菌唑的敏感性之间存在正相关（r = 0.617）。对喹氧灵抗性的小麦白粉病菌分离株对丙硫菌唑的敏感性略低于对喹氧灵敏感的分离株；然而，丙硫菌唑对这些分离株的活性仍远高于喹氧灵。在叶盘试验中检测的65个葡萄白粉病菌分离株中，丙硫菌唑和喹氧灵之间的敏感性关系更强（r = 0.874）。丙硫菌唑的敏感性值显著低于喹氧灵，证实了丙硫菌唑对两种病原菌的内在活性更高。
鉴于白粉病抗性发展的历史以及观察到的与喹氧灵的敏感性关系，特别是在葡萄白粉病菌中，我们得出结论，使用喹氧灵可能会影响对丙硫菌唑产生抗性的风险。基于这些结果，作者建议将丙硫菌唑和喹氧灵一起用于抗性治理。
