Alvarez L A, Vicent A, Soler J M, De la Roca E, Bascón J, García-Jiménez J
Instituto Agroforestal Mediterráneo, Universidad Politécnica de Valencia, Camino de Vera s/n, 46022 - Valencia, Spain.
Bayer CropScience S.L., Polígono Industrial El Pla, 30, Alcasser, 46290 - Valencia, Spain.
Plant Dis. 2008 Sep;92(9):1357-1363. doi: 10.1094/PDIS-92-9-1357.
Since 2002, considerable losses of Clementine trees (Citrus clementina) have been observed in Spain due to Phytophthora branch canker of citrus caused by Phytophthora citrophthora. Due to the low efficiency of the available cultural and genetic control measures, application of fungicides is required for economic management of the disease. Fosetyl-Al, metalaxyl, and its enantiomer mefenoxam are the only systemic fungicides registered for control of Phytophthora diseases in Spain. However, their efficacy has not been tested against Phytophthora branch canker. Greenhouse and field experiments were conducted for 3 years in Spain to evaluate the ability of these fungicides and application methods to reduce lesion expansion. Nevertheless, with the inoculation technique used, it was not possible to evaluate the protective activity of fungicides, which can play an important role in their performance under field conditions. None of the fungicide treatments inhibited lesion expansion when applications were made on a curative basis. The residual effect was better on young than on mature trees. Paint treatments were generally more effective in reducing lesion expansion that drip chemigation or foliar sprays. However, this application method is laborious and becomes uneconomical in Spain. Trunk and branch sprays as well as long-term programs of foliar sprays or drip chemigation for control of spring and autumn infections are proposed as targets for future research.
自2002年以来，西班牙观察到由于柑橘褐腐疫霉引起的柑橘疫霉枝枯病，克莱门氏小柑橘树（Citrus clementina）出现了大量损失。由于现有栽培和遗传防治措施效率低下，为了对该病进行经济管理，需要施用杀菌剂。乙膦铝、甲霜灵及其对映体精甲霜灵是西班牙仅有的登记用于防治疫霉病的内吸性杀菌剂。然而，它们对柑橘疫霉枝枯病的防治效果尚未得到测试。在西班牙进行了为期3年的温室和田间试验，以评估这些杀菌剂及其施用方法减少病斑扩展的能力。然而，使用所采用的接种技术，无法评估杀菌剂的保护活性，而这在田间条件下对其性能可能起到重要作用。当进行治疗性施药时，没有一种杀菌剂处理能抑制病斑扩展。残留效果在幼树比在成年树上更好。涂药处理在减少病斑扩展方面通常比滴灌施药或叶面喷雾更有效。然而，这种施药方法费力，在西班牙变得不经济。建议将树干和树枝喷雾以及用于控制春季和秋季感染的叶面喷雾或滴灌施药长期方案作为未来的研究目标。
