Yandoc C B, Rosskopf E N, Shah D A, Albano J P
Former Postdoctoral Research Associate.
United States Department of Agriculture-Agricultural Research Service (USDA-ARS), United States Horticultural Laboratory, Fort Pierce, FL 34945.
Plant Dis. 2007 Nov;91(11):1477-1483. doi: 10.1094/PDIS-91-11-1477.
Experiments were carried out in a greenhouse to determine the effect of fertilizer concentration (0, 0.5, 1.0, and 2.0× Hoagland solutions) and various commercial biopesticides on the severity of Phytophthora nicotianae infection of Madagascar periwinkle. Application of biopesticides and fertilizer concentration significantly influenced the severity of infection, but there was no significant effect from the interaction of these two factors. Overall, disease severity showed a tendency to increase with the concentration of applied fertilizer. Compared with the control plants, disease was significantly less severe in plants that were treated with the biopesticides, except for plants treated with metabolites of Myrothecium verrucaria (DiTera). However, only the products containing potassium phosphonates and potassium phosphates (FNX-100 and FNX-2500) provided a satisfactory level of control when compared with either the control plants or those that received any of the other products tested. Additional experiments were carried out in growth chambers to test the effects of increasing fertilizer concentrations in plants that were inoculated with different P. nicotianae inoculum levels. In these trials, there was no consistent indication that disease is most severe in plants that received the highest fertilizer concentration even at the highest inoculum level.
在温室中进行了实验，以确定肥料浓度（0、0.5、1.0和2.0倍霍格兰溶液）以及各种商业生物农药对长春花疫霉感染严重程度的影响。生物农药的施用和肥料浓度显著影响感染的严重程度，但这两个因素的相互作用没有显著影响。总体而言，病害严重程度呈现出随施肥浓度增加而上升的趋势。与对照植株相比，除了用疣孢漆斑菌（DiTera）代谢产物处理的植株外，用生物农药处理的植株病害严重程度显著较低。然而，与对照植株或接受任何其他测试产品处理的植株相比，只有含膦酸钾和磷酸钾的产品（FNX - 100和FNX - 2500）提供了令人满意的防治效果。在生长室中进行了额外的实验，以测试在接种不同水平烟草疫霉接种物的植株中增加肥料浓度的影响。在这些试验中，没有一致的迹象表明，即使在最高接种水平下，接受最高肥料浓度的植株病害最严重。
