Carroll Christine L, Carter Colin A, Goodhue Rachael E, Lawell C-Y Cynthia Lin, Subbarao Krishna V
First author: College of Agriculture, California State University, Chico 95929; second and third authors: Department of Agricultural and Resource Economics, University of California, One Shields Avenue, Davis 95616; fourth author: Charles H. Dyson School of Applied Economics and Management, 407 Warren Hall, Cornell University, Ithaca, NY 14853; and fifth author: Department of Plant Pathology, University of California, Davis, c/o U.S. Agricultural Research Station, 1636 E. Alisal Street, Salinas 95616.
Phytopathology. 2018 Feb;108(2):160-171. doi: 10.1094/PHYTO-03-17-0083-RVW. Epub 2017 Oct 16.
Plant pathogens migrate to new regions through human activities such as trade, where they may establish themselves and cause disease on agriculturally important crops. Verticillium wilt of lettuce, caused by Verticillium dahliae, is a soilborne fungus that was introduced to coastal California via infested spinach seeds. It has caused significant losses for lettuce growers. Once introduced, Verticillium wilt could be managed by fumigating with methyl bromide and chloropicrin, but this option is no longer available. Growers can also manage the disease by planting broccoli or not planting spinach. These control options require long-term investments for future gain. Verticillium wilt can also be prevented or controlled by testing and providing spinach seeds with little or no V. dahliae infestation. However, seed companies have been reluctant to test or clean spinach seeds, as spinach crops are not affected by Verticillium wilt. Thus, available control options are affected by externalities. Renters and other producers with short time horizons will not undertake long-term investments and seed companies do not take into account the effect of their decision not to test on lettuce producers. We review the literature on the economics of managing crop disease; discuss the economics of managing Verticillium wilt; and review the recent research on the externalities that arise with short-term growers, and between seed companies and growers due to Verticillium wilt. An externality arises whenever the actions of one individual or firm affects the payoffs to another individual or firm not involved in a specific transaction. These externalities have important implications for the management of Verticillium wilt and, more broadly, for the management of migratory pathogens and the diseases they cause in agriculture in general. This review is of interest to policy-makers, the producers, marketers, seed companies, and researchers.
植物病原体通过贸易等人类活动迁移到新的地区，在那里它们可能立足并对重要农作物造成病害。由大丽轮枝菌引起的生菜黄萎病是一种土传真菌，它通过受侵染的菠菜种子被引入加利福尼亚沿海地区。这给生菜种植者造成了重大损失。一旦引入，可用甲基溴和氯化苦熏蒸来管理生菜黄萎病，但这种选择已不再可行。种植者也可以通过种植西兰花或不种植菠菜来管理这种病害。这些控制措施需要长期投资以获取未来收益。通过检测并提供几乎没有或没有大丽轮枝菌侵染的菠菜种子，也可以预防或控制生菜黄萎病。然而，种子公司一直不愿检测或清理菠菜种子，因为菠菜作物不受黄萎病影响。因此，可用的控制措施受到外部因素的影响。租期较短的租户和其他生产者不会进行长期投资，种子公司也没有考虑到他们不进行检测的决定对生菜生产者的影响。我们回顾了关于作物病害管理经济学的文献；讨论了生菜黄萎病管理的经济学；并回顾了近期关于短期种植者以及由于生菜黄萎病在种子公司和种植者之间产生的外部因素的研究。只要一个个人或公司的行为影响到未参与特定交易的另一个人或公司的收益，就会产生外部因素。这些外部因素对生菜黄萎病的管理具有重要意义，更广泛地说，对迁移性病原体及其在农业中引起的病害的管理也具有重要意义。本综述对政策制定者、生产者、营销商、种子公司和研究人员都具有参考价值。
