Funahashi F, Parke J L
Department of Crop and Soil Science.
Department of Crop and Soil Science and Department of Botany and Plant Pathology, Oregon State University, Corvallis 97331.
Plant Dis. 2016 Feb;100(2):438-443. doi: 10.1094/PDIS-04-15-0453-RE. Epub 2015 Dec 19.
Infested container nursery beds are an important source of soilborne Phytophthora spp. for initiating disease through movement with surface water or splashing onto foliage. We investigated the effects of soil solarization, alone or with subsequent amendment with a Trichoderma asperellum biocontrol agent, on the survival of Phytophthora spp. inoculum. In field trials conducted with Phytophthora ramorum in San Rafael, CA and with P. pini in Corvallis, OR, infested rhododendron leaf inoculum was buried at 5, 15, and 30 cm below the soil surface. Solarization for 2 or 4 weeks during summer 2012 eliminated recovery of Phytophthora spp. buried at all depths in California trial 1, at 5 and 15 cm in California trial 2, but only at 5 cm in Oregon. There was no significant reduction of Phytophthora spp. recovery after T. asperellum application. Although the population densities of the introduced T. asperellum at the 5-cm depth were often two- to fourfold higher in solarized compared with nonsolarized plots, they were not significantly different (P = 0.052). Soil solarization appears to be a promising technique for disinfesting the upper layer of soil in container nurseries under certain conditions.
受侵染的容器育苗床是土壤传播疫霉菌的重要来源，可通过地表水移动或溅到叶片上引发病害。我们研究了土壤太阳能消毒单独使用或随后用棘孢木霉菌生物防治剂改良对疫霉菌接种体存活的影响。在加利福尼亚州圣拉斐尔对樟疫霉以及在俄勒冈州科瓦利斯对松疫霉进行的田间试验中，将受侵染的杜鹃花叶片接种体埋在土壤表面以下5厘米、15厘米和30厘米处。2012年夏季进行2周或4周的太阳能消毒后，在加利福尼亚试验1中，所有深度埋入的疫霉菌都无法再分离得到；在加利福尼亚试验2中，5厘米和15厘米深度埋入的疫霉菌无法再分离得到，但在俄勒冈州仅5厘米深度埋入的疫霉菌无法再分离得到。施用棘孢木霉菌后，疫霉菌的分离数量没有显著减少。尽管在太阳能消毒处理的地块中，5厘米深度处引入的棘孢木霉菌种群密度通常比未消毒地块高两到四倍，但差异不显著（P = 0.052）。在某些条件下，土壤太阳能消毒似乎是一种对容器育苗床上层土壤进行消毒的有前景的技术。
