Mary Bianchi

Research Priorities for Coordinating Management of Food Safety and Water Quality

Efforts to exclude disease organisms from farms growing irrigated lettuce and leafy vegetables on Californias central coast are conflicting with traditionally accepted strategies to protect surface water quality. To begin resolving this dilemma, over 100 officials, researchers, and industry representatives gathered in April 2007 to set research priorities that could lead to effective co-management of both food safety and water quality. Following the meeting, research priorities were refined and ordered by way of a Delphi process completed by 35 meeting participants. Although water quality and food safety experts conceptualized the issues differently, there were no deep disagreements with respect to research needs. Top priority was given to investigating the fate of pathogens potentially present on farms. Intermediate priorities included characterizing the influence of specific farm management practices on food safety and improving our understanding of vector processes. A scientific subdiscipline focusing on competing risks is needed to characterize and resolve conflicts between human and environmental health.

Spore Trapping and Pathogenicity of Fungi in the Botryosphaeriaceae and Diaporthaceae Associated with Avocado Branch Canker in California

Avocado branch canker in California is caused by a complex of fungal species in the families Botryosphaeriaceae and Diaporthaceae. As the popularity of avocado fruit increases, California growers are under pressure to increase their productivity in order to compete with imports. One way to increase production is through high-density planting, which entails intense canopy management, possibly leaving the trees vulnerable to infection through pruning wounds. A spore trap study was undertaken to determine the seasonal spore discharge of Botryosphaeriaceous and Diaporthaceous fungi. Based on colony counts, the highest population of Botryosphaeriaceous fungi (68%) occurred during or soon after precipitation events, which coincided with the winter months of December, January, and February. The spring and fall seasons had lower numbers of spores trapped (at 13 and 17%, respectively), with few spores trapped in the summer season. For members of the Diaporthaceae family, spores trapped were almost evenly split between winter and fall seasons (50 and 49%, respectively), with few to no spores trapped in the spring and summer seasons. A pathogenicity test of six fungi of Botryosphaeriaceae and one fungus of Diaporthaceae was conducted in the greenhouse. Internal plant vascular lesion lengths resulting from inoculation with any of the seven fungal species differed significantly from the noninoculated control. These studies suggest that pruning during the drier parts of the year would minimize infection by fungi in the Botryosphaeriaceae and Diaporthaceae families.

Co-management: Balancing Food Safety, the Environment, and the Bottom Line

Growers and distributors of fresh produce have long realized that reliably safe products and responsible use of resources inspire brand trust and consumer loyalty. Balancing food safety and resource conservation goals has become a vital element of produce industry management throughout the supply chain. Co-management is a process that seeks to balance food safety and sustainability goals in the context of maintaining a sound bottom line. The resources to develop effective co-management strategies lie within diverse communities of practice, including agricultural producers, food safety and wildlife professionals, conservation professionals, and academics with primary focus on any the above areas.The economic loss incurred from fields that must be abandoned before harvest due to fecal contamination can be significant. In addition, compliance with both food safety and conservation goals may generate additional operational costs. Key research questions remain, many defined during the critical conversations surrounding on-farm decisions regarding co-management. Additionally, responsibility lies with the research community for creating an open and integrated approach to interpretation, extension, and implementation of research results surrounding contamination, transport and survival of pathogens in the production environment.

Identifying Your Farm Water Quality Goals

Author(s): Bianchi, Mary | Abstract: This is reference sheet 7.1 in the Farm Water Quality Planning series.