Yandoc-Ables Camilla B, Rosskopf Erin N, Lamb Elizabeth M
former Postdoctoral Research Associate.
Research Microbiologist, United States Horticultural Research Laboratory, United States Department of Agriculture-Agricultural Research Service, Fort Pierce, FL 34945.
Plant Dis. 2007 Dec;91(12):1651-1656. doi: 10.1094/PDIS-91-12-1651.
Experiments were conducted in the greenhouse to determine the efficacy of two phosphonate-containing fungicides (FNX-100 and FNX-2500) against Phytophthora crown rot of pumpkin. The experiments were designed to determine the effects of crop cultivar, application method (soil drench versus foliar spray), and phosphonate concentration on the level of effectiveness of a crown rot management strategy using phosphonates. Pumpkin cultivar, treatment (type of fungicide product), phosphonate concentration, and application method significantly influenced the level of Phytophthora crown rot control. Between the two fungicides, only FNX-100 suppressed Phytophthora crown rot in pumpkin. For cv. Phantom, the highest level of control was achieved with the drench application of 3.0% FNX-100 whereas, for cv. Spooktacular, all three concentrations of FNX-100 (1.0, 2.0, and 3.0%, vol/vol) applied as a soil drench suppressed or significantly reduced the severity of crown rot. Additional experiments using zucchini as test plants demonstrated that, at the concentrations tested, FNX-100 was more efficacious than FNX-2500 in controlling Phytophthora crown rot and that zucchini cultivar or FNX-100 concentration did not significantly influence crown rot control with phosphonates. In this study, FNX-100, which is not currently labeled for use in vegetables, provided satisfactory disease control in both pumpkin and zucchini whereas FNX-2500, a foliar fungicide comprised of the phosphate/phosphonates and copper, manganese, and zinc, did not significantly affect disease severity. This study, albeit limited in scope, showed that cultivar selection may play an important role in the successful management of Phytophthora crown rot on cucurbits with phosphonates, information which may be useful in designing additional tests and developing management strategies for pumpkin and zucchini that are grown in the field.
在温室中进行了实验，以确定两种含膦酸酯的杀菌剂（FNX - 100和FNX - 2500）对南瓜疫霉根腐病的防治效果。实验旨在确定作物品种、施用方法（土壤浇灌与叶面喷施）以及膦酸酯浓度对使用膦酸酯的根腐病管理策略有效性水平的影响。南瓜品种、处理（杀菌剂产品类型）、膦酸酯浓度和施用方法对疫霉根腐病的防治水平有显著影响。在这两种杀菌剂中，只有FNX - 100能抑制南瓜疫霉根腐病。对于“幻影”品种，使用3.0% FNX - 100进行浇灌处理可实现最高防治水平；而对于“惊人”品种，以土壤浇灌方式施用的所有三种浓度的FNX - 100（1.0%、2.0%和3.0%，体积/体积）均能抑制或显著降低根腐病的严重程度。使用西葫芦作为试验植物的额外实验表明，在所测试的浓度下，FNX - 100在防治疫霉根腐病方面比FNX - 2500更有效，并且西葫芦品种或FNX - 100浓度对使用膦酸酯防治根腐病没有显著影响。在本研究中，目前未标注可用于蔬菜的FNX - 100在南瓜和西葫芦中均提供了令人满意的病害防治效果，而由磷酸盐/膦酸酯以及铜、锰和锌组成的叶面杀菌剂FNX - 2500对病害严重程度没有显著影响。本研究虽然范围有限，但表明品种选择可能在使用膦酸酯成功管理葫芦科作物疫霉根腐病方面发挥重要作用，这些信息可能有助于设计更多试验以及制定在田间种植的南瓜和西葫芦的管理策略。
