Habili Nuredin, Nutter Forrest W
Senior Research Scientist, Cooperative Research Centre for Viticulture and CSIRO Division of Horticulture, GPO Box 350 Adelaide, South Australia 5001.
Associate Professor, Department of Plant Pathology, Iowa State University, Ames 50011.
Plant Dis. 1997 Jun;81(6):625-628. doi: 10.1094/PDIS.1997.81.6.625.
An epidemic of grapevine leafroll disease (GLD), caused by grapevine leafroll-associated virus 3 (GLRaV-3), was monitored over an 11-year period in Nuriootpa, South Australia. Inoculum originated from infected budwood, and initial GLD incidence at the time of transplanting in 1986 was 23.1%. Infected vines were planted in a random spatial pattern. Change in disease incidence was not observed until 8 years after planting, when disease incidence increased to 27.9%. Disease incidence increased to 51.9% by 1996. Disease progress and rate curves (dy/dt versus time) indicated that the logistic (R = 96.2) and Gompertz (R = 96.3) growth models would best describe disease progress. However, the logistic model, which has a simpler data transformation with fewer model assumptions, was chosen for the purpose of comparing this epidemic (South Australia) with a GLRaV-3 epidemic in Cabernet Sauvignon grapevines in New Zealand. The logistic rate of GLD spread with respect to time was 0.35 logit/year in South Australia and was nearly three times faster (1.19 logits/year) for GLRaV-3 spread in New Zealand. Ordinary runs analyses indicated that the arrangement of infected vines within rows in South Australia was random up to 8 years after transplanting but subsequently became highly aggregated. Thus, GLD-infected plants are contributing to new infections (i.e., there is evidence for plant-to-plant spread), and a biotic vector with a steep dispersal gradient from each point source is likely to be involved.
在南澳大利亚的努里奥塔巴，对由葡萄卷叶相关病毒3（GLRaV-3）引起的葡萄卷叶病（GLD）疫情进行了为期11年的监测。接种源来自受感染的接穗，1986年移栽时GLD的初始发病率为23.1%。受感染的葡萄藤以随机空间模式种植。直到种植8年后才观察到发病率的变化，此时发病率增至27.9%。到1996年，发病率增至51.9%。病情进展和速率曲线（dy/dt对时间）表明，逻辑斯蒂（R = 96.2）和冈珀茨（R = 96.3）生长模型最能描述病情进展。然而，为了将此次疫情（南澳大利亚）与新西兰赤霞珠葡萄藤中GLRaV-3疫情进行比较，选择了数据转换更简单且模型假设更少的逻辑斯蒂模型。在南澳大利亚，GLD传播的逻辑斯蒂速率为每年0.35对数单位，而在新西兰，GLRaV-3传播的速率（每年1.19对数单位）几乎快三倍。普通游程分析表明，在南澳大利亚，移栽后8年内，受感染葡萄藤在行内的排列是随机的，但随后变得高度聚集。因此，受GLD感染的植株正在导致新的感染（即有植株间传播的证据），并且可能涉及一种从每个点源具有陡峭扩散梯度的生物传播介体。
