Thomas-Sharma S, Andrade-Piedra J, Carvajal Yepes M, Hernandez Nopsa J F, Jeger M J, Jones R A C, Kromann P, Legg J P, Yuen J, Forbes G A, Garrett K A
First, fourth, and eleventh authors: Department of Plant Pathology, Kansas State University, Manhattan; first author: Department of Plant Pathology, University of Wisconsin-Madison, Madison; second author: International Potato Center, Lima, Peru; third author: International Center for Tropical Agriculture, Cali, Colombia; fourth and eleventh authors: Plant Pathology Department, Institute for Sustainable Food Systems, and Emerging Pathogens Institute, University of Florida, Gainesville; fifth author: Centre for Environmental Policy, Imperial College London; sixth author: Institute of Agriculture, University of Western Australia, Crawley, Australia; seventh author: International Potato Center, Quito, Ecuador; eighth author: International Institute of Tropical Agriculture, Dar es Salaam, Tanzania; ninth author: Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, Uppsala, Sweden; and tenth author: International Potato Center, Kunming, China.
Phytopathology. 2017 Oct;107(10):1123-1135. doi: 10.1094/PHYTO-09-16-0340-R. Epub 2017 Jul 6.
Pathogen buildup in vegetative planting material, termed seed degeneration, is a major problem in many low-income countries. When smallholder farmers use seed produced on-farm or acquired outside certified programs, it is often infected. We introduce a risk assessment framework for seed degeneration, evaluating the relative performance of individual and combined components of an integrated seed health strategy. The frequency distribution of management performance outcomes was evaluated for models incorporating biological and environmental heterogeneity, with the following results. (1) On-farm seed selection can perform as well as certified seed, if the rate of success in selecting healthy plants for seed production is high; (2) when choosing among within-season management strategies, external inoculum can determine the relative usefulness of 'incidence-altering management' (affecting the proportion of diseased plants/seeds) and 'rate-altering management' (affecting the rate of disease transmission in the field); (3) under severe disease scenarios, where it is difficult to implement management components at high levels of effectiveness, combining management components can be synergistic and keep seed degeneration below a threshold; (4) combining management components can also close the yield gap between average and worst-case scenarios. We also illustrate the potential for expert elicitation to provide parameter estimates when empirical data are unavailable. [Formula: see text] Copyright © 2017 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .
在营养繁殖种植材料中病原体的积累，即种子退化，是许多低收入国家面临的一个主要问题。当小农户使用农场生产的种子或从认证项目之外获取的种子时，这些种子往往受到感染。我们引入了一个种子退化风险评估框架，评估综合种子健康策略中各个组成部分及其组合的相对性能。对纳入生物和环境异质性的模型评估了管理绩效结果的频率分布，结果如下：（1）如果为种子生产选择健康植株的成功率较高，农场内种子选择的效果可以与认证种子相当；（2）在季节内管理策略中进行选择时，外部接种体可决定“发病率改变管理”（影响患病植株/种子的比例）和“传播速率改变管理”（影响田间疾病传播速率）的相对有效性；（3）在严重病害情况下，难以高效实施管理措施时，组合管理措施具有协同作用，可使种子退化保持在阈值以下；（4）组合管理措施还可缩小平均情况与最坏情况之间的产量差距。我们还说明了在缺乏实证数据时，专家判断提供参数估计值的可能性。[公式：见正文] 版权所有© 2017作者。本文是一篇开放获取文章，根据知识共享署名 - 非商业性使用 - 禁止演绎4.0国际许可协议发布。
