Biophysical scaling and the passive dispersal of fungus spores: relationship to integrated pest management strategies
Biophysical scaling and the passive dispersal of fungus spores: relationship to integrated pest management strategies
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DOI：
10.1016/s0168-1923(99)00072-6
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发表时间：
1999-11-30
影响因子：
6.2
通讯作者：
Aylor, DE
中科院分区：
文献类型：
--
作者：
Aylor, DE
成功的综合虫害管理策略取决于对进入管理区的“移民”接种物的准确评估。植物病原真菌孢子的传播是一系列相互联系的事件。从孢子产生开始，传播依次取决于孢子从基质中释放或去除，孢子从冠层空间逃逸，孢子云被湍流风运输和稀释，运输过程中接种物活力的丧失，孢子通过沉淀从大气中去除，孢子沉积在宿主组织上，以及沉积孢子在易感宿主组织上的感染效率。所有这些成分都在时间和空间上发生变化，这对空气生物学家提出了挑战，以确定控制疾病传播的关键生物物理过程。其中一些过程将以两种植物疾病为例进行说明：由病原体黑星病菌引起的苹果黑星病和由病原体烟草霜霉引起的烟草蓝霉病。这两种病原体都是通过空气中的孢子传播的。苹果黑星病病原体的子囊孢子主要在降雨事件期间通过空气传播，而烟草赤星病菌孢子囊主要在干燥对流条件下通过空气传播。传播的初步成功取决于阵风，阵风允许孢子从作物冠层或地面上方的空气边界层逃逸。当时的小气候条件（如白天或黑夜、下雨或不下雨）和孢子释放的位置（树冠的上部或下部）对病原体随后的传播有显著的影响。在远距离疾病传播过程中，疾病锋面边界的推进速度可能比疾病在当地传播的速度快6倍。将以烟草蓝霉病为例讨论这种明显的异常。在空间异质分布的寄主中，疾病前沿的移动速率主要取决于当地疾病发展的相对速率、传播功能的长度尺度、寄主植物区域之间的距离以及这些寄主区域的面积。一些因素，如患病移植物的地面运输和病原体对杀真菌剂敏感性的变化，有时可以超越长距离孢子传播的生物物理限制。(C)1999 Elsevier Science B.V.保留所有权利。
Successful integrated pest management strategies depend on an accurate evaluation of 'immigrant' inoculum coming into a managed area. Dispersal of plant pathogenic fungus spores is comprised of a series of inter-connected events. Starting with spore production, dispersal depends, in turn, on spore release or removal from a substrate, spore escape from the canopy space, transport and dilution of a spore cloud by turbulent wind, loss of inoculum viability during transport, spore removal from the atmosphere by precipitation, spore deposition on host tissue, and the infection efficiency of deposited spores on susceptible host tissue. All of these components change in time and space, challenging the aerobiologist to identify critical biophysical processes that control disease spread.Some of these processes will be illustrated for two plant diseases: apple scab caused by the pathogen Venturia inaequalis and tobacco blue mold caused by the pathogen Peronospora tabacina. Both these pathogens are dispersed by airborne spores. Ascospores of the apple scab pathogen become airborne primarily during rain events, while P. tabacina sporangia become airborne primarily during dry, convective conditions. Initial success of dispersal depends on, wind gusts which allow escape of spores from a crop canopy or the boundary layer of air just above the ground. Microclimatic conditions at the time (e.g. day or night, rain or no rain) and the location of spore release (upper or lower canopy) can have a significant effect on subsequent dispersal of pathogens.The rate of advance of a disease frontal boundary during long-distance disease spread can be as much as six times faster than the local rate of disease spread. This apparent anomaly will be discussed using tobacco blue mold as an example. The rate of movement of the disease front in a spatially heterogeneous distribution of hosts, is determined largely by the relative rate of local disease development, the length scale of the dispersal function, distance between regions of host plants, and the area of those host regions. Factors such as ground transportation of diseased transplants and changes in the pathogen's sensitivity to fungicides can, at times, override the biophysical constraints on long-distance spore dispersal. (C) 1999 Elsevier Science B.V. All rights reserved.