Phytopathology. 2000 Dec;90(12):1307-12. doi: 10.1094/PHYTO.2000.90.12.1307.
ABSTRACT The use of host diversity as a tool for management of potato late blight has not been viewed as promising in the past. But the increasing importance of late blight internationally has brought new consideration to all potential management tools. We studied the effect of host diversity on epidemics of potato late blight in Oregon, where there was little outside inoculum. The experimental system consisted of susceptible potato cv. Red LaSoda and a highly resistant breeding selection, inoculated with local isolates of US-8 Phytophthora infestans. Potatoes were grown in single-genotype plots and also in a mixture of 10 susceptible and 26 resistant potato plants. Half of the plots received inoculation evenly throughout the plot (general inoculation) and half received an equal quantity of inoculum in only one corner of the plot (focal inoculation). The area under the disease progress curve (AUDPC) was greater in single genotype stands of susceptible cv. Red LaSoda inoculated throughout the plot than with stands inoculated in one focus. The host-diversity effect on foliar late blight was significant in both years of the investigation; the AUDPC was reduced by an average of 37% in 1997 and 36% in 1998, compared with the mean disease level for the potato genotypes grown separately. Though the evidence for influence of inoculum pattern on host-diversity effects was weak (P = 0.15), in both years there was a trend toward greater host-diversity effects for general inoculation. Statistical significance of host-diversity effects on tuber yield and blight were found only in one of the two years. In that year, tuber yield from both the resistant and susceptible cultivar was increased in mixtures compared with single genotype stands and tuber blight was decreased in mixtures for susceptible cv. Red LaSoda.
摘要 过去，人们认为利用宿主多样性作为防治马铃薯晚疫病的手段并不具有前景。但是，晚疫病在国际上的重要性日益增加，使所有潜在的管理工具都受到了新的关注。我们研究了宿主多样性对俄勒冈州马铃薯晚疫病流行的影响，该地区几乎没有外来接种体。实验系统由易感马铃薯品种 Red LaSoda 和一个高度抗性的选育品种组成，用当地分离的 US-8 晚疫病菌接种。马铃薯种植在单基因型的地块中，也种植在 10 个易感和 26 个抗性马铃薯植株的混合物中。一半的地块均匀地接受整个地块的接种（普遍接种），另一半的地块仅在地块的一个角落接受等量的接种（焦点接种）。在整个地块普遍接种的易感 Red LaSoda 单基因型地块的病害进展曲线下面积（AUDPC）大于在一个焦点接种的地块。在调查的两年中，宿主多样性对叶片晚疫病都有显著影响；1997 年和 1998 年，AUDPC 分别平均降低了 37%和 36%，与单独种植的马铃薯基因型的平均病害水平相比。尽管接种模式对宿主多样性效应的影响证据较弱（P = 0.15），但在这两年中，普遍接种的宿主多样性效应呈增加趋势。只有在其中一年中，宿主多样性对块茎产量和疫病的影响才具有统计学意义。在那一年，与单基因型地块相比，抗性和易感品种的块茎产量在混作中增加，易感品种 Red LaSoda 的块茎疫病减少。
