Department of plant Pathology and weed research and Weed Research, Institute of Plant Protection, ARO, the Volcani Center, Dagan, Israel.
Phytopathology. 2010 Jan;100(1):97-104. doi: 10.1094/PHYTO-100-1-0097.
The individual and joint effects of covering the soil with polyethylene mulch before planting and fungicides commonly used by organic growers on tomato late blight (caused by Phytophthora infestans) were studied in three experiments conducted from 2002 to 2005. Application of fungicides resulted in inconsistent and insufficient late blight suppression (control efficacy +/- standard error of 34.5 +/- 14.3%) but the polyethylene mulch resulted in consistent, effective, and highly significant suppression (control efficacy of 83.6 +/- 5.5%) of the disease. The combined effect of the two measures was additive. In a second set of three experiments carried out between 2004 and 2006, it was found that the type of polyethylene mulch used (bicolor aluminized, clear, or black) did not affect the efficacy of late blight suppression (control efficacy of 60.1 to 95.8%) and the differences in the effects among the different polyethylene mulches used were insignificant. Next, the ability of the mulch to suppress cucumber downy mildew (caused by Pseudoperonospora cubensis) was studied in four experiments carried out between 2006 and 2008. The mulch effectively suppressed cucumber downy mildew but the effect was less substantial (control efficacy of 34.9 +/- 4.8%) than that achieved for tomato late blight. The disease-suppressing effect of mulch appeared to come from a reduction in leaf wetness duration, because mulching led to reductions in both the frequency of nights when dew formed and the number of dew hours per night when it formed. Mulching also reduced relative humidity in the canopy, which may have reduced sporulation.
在 2002 年至 2005 年进行的三项实验中，研究了在种植前用聚乙烯覆盖土壤和有机种植者常用的杀菌剂对番茄晚疫病（由疫霉引起）的单独和联合作用。杀菌剂的应用导致晚疫病抑制效果不一致且不充分（控制效果为 34.5%±14.3%），但聚乙烯覆盖物可有效、一致地抑制该疾病（控制效果为 83.6%±5.5%）。这两种措施的联合效果是相加的。在 2004 年至 2006 年进行的第二组三项实验中，发现所使用的聚乙烯覆盖物类型（双色镀铝、透明或黑色）不会影响晚疫病抑制效果（控制效果为 60.1%至 95.8%），且使用不同聚乙烯覆盖物之间的效果差异不显著。接下来，在 2006 年至 2008 年进行的四项实验中研究了覆盖物抑制黄瓜霜霉病（由古巴假霜霉菌引起）的能力。覆盖物可有效抑制黄瓜霜霉病，但效果不如番茄晚疫病显著（控制效果为 34.9%±4.8%）。覆盖物的疾病抑制作用似乎来自叶片湿润持续时间的减少，因为覆盖物导致结露的夜晚频率和每次结露的露水小时数减少。覆盖物还降低了冠层中的相对湿度，这可能减少了孢子形成。
