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Tomato bacterial diseases cause significant losses annually to fresh market, processing and greenhouse producers worldwide. As researchers continue to better understand the biology of bacterial pathogens and develop effective management strategies to reduce disease incidence and severity, improved methods are needed to translate and exchange this new knowledge to a diverse and dynamic group of tomato stakeholders. However, identifying tools or methods that present knowledge in a way that will facilitate uptake and application of the knowledge can be challenging. In addition, very little science-based information is available on the best way to deliver plant disease management strategies to vegetable producers. Based on surveys conducted to identify midwestern vegetable producers’ preferences for receiving information regarding food safety hazards and the fact that the need for communication in society is heterogeneous and requires differentiation according to target groups, innovative factsheets for bacterial leaf spot (BLS), bacterial speck, bacterial canker, and pith necrosis were developed. Each factsheet contains science-based information that incorporates recent changes in the taxonomic classification, epidemiology, management and identification of the pathogens that cause these diseases. The information provided is relevant to new producers or home gardeners (beginners), experienced producers (advanced) and plant disease diagnosticians. Information from all three levels of knowledge is summarized into one downloadable factsheet that is available in English and Spanish. Additionally, uncommon terminology is defined in English and Spanish, images of diseases with similar and potentially confusing symptoms are provided and resources for diagnosing each disease are included. The factsheets were published on January 23, 2013 at www.vegetablediseasefacts.com. Over a 2-month period the factsheets had 93 new visitors and 112 returning visitors. The bounce rate for new and returning visitors was 8.6 and 52.7%, respectively. While the majority of visitors (94.7%) were from Ohio, visitors were also from Florida, Illinois, Louisiana, North Carolina, New York, Pennsylvania, Virginia, and Wisconsin. International visitors were from Guatemala, India, China, Colombia, Egypt, Iran, Italy, Mexico and Senegal. Bacterial leaf spot was the most frequently visited and downloaded disease factsheet; followed by bacterial canker, pith necrosis and bacterial speck. User engagement of each factsheet continues to be monitored and additional factsheets targeting high tunnel and organic tomato producers are currently being developed.

Powdery mildew (Oidium sp.) is an important disease of greenhouse-produced tomatoes. The severity of the disease, the widespread distribution of the pathogen, and its ability to develop insensitivity to fungicides with a narrow mode of action requires the identification of viable alternatives to conventional fungicides. Various products are available or in development that have the potential to contribute to the management of powdery mildew of tomato. Biorational products and fungicides including Cease and Serenade ASO (Bacillus subtilis QST 713 strain), Actinovate (Streptomyces lydicus), JMS stylet oil (paraffinic oil), Kocide 3000 (copper hydroxide), Microthiol Disperss (sulfur), Milstop (potassium bicarbonate), OxiDate (hydrogen dioxide), Rally 40WSP (myclobutanil), Regalia (extract of Reynoutria sachalinensis), Nufarm-Cuproxat concentrate (copper sulfate), cedar oil, citronella, clove oil, cottonseed oil, lemongrass, Ortho-Eco sense 3-in-1 Rose and Flower Care (sulfur and pyrethrin), Ortho-Eco sense Garden Disease Control (copper octanoate), whole milk, Prestop (Gliocladium catenulatum J1446), and Quintec (quinoxyfen) were tested. The experiments were done twice, each with four replicates per treatment. The severity of powdery mildew on foliage and phytotoxicity were evaluated using a scale of 0-100% foliage affected. In both experiments the severity of powdery mildew was moderate (~20% foliage affected). Cottonseed oil, Rally 40WSP, whole milk and Microthiol Disperss provided >87% control of powdery mildew compared to the non-treated control in both experiments, with little or no phytotoxicity. Cedar oil, lemongrass, Regalia, citronella, both Ortho-Eco sense products, clove oil, Milstop, JMS stylet oil, and Quintec reduced the severity of powdery mildew at least 39% in the first experiment and 62% in the second experiment. Many of the products were slightly phytotoxic on tomato foliage, but JMS stylet oil, cedar oil and citronella damaged foliage significantly compared to the non-treated control in both experiments.

One half of fresh tomato sales in the US are from greenhouse grown crops. Fresh tomato was linked to a number of foodborne disease outbreaks. Collectively, foodborne and phytopathogen hazards threaten both public health and economic viability of the greenhouse industry. Management practices in tomato greenhouses in North America were documented previously. In this study, a systematic, internet-based, iterative Delphi method was used to gauge opinions about the potential impact of various greenhouse management factors (water management, workers, environment and greenhouse design, equipment sanitation, animals, waste, and traceability) on food safety. The pretested questionnaire was distributed to 20 national and international experts in food safety of fresh fruits and vegetables. The Delphi process was repeated until the criteria for consensus were satisfied (expert agreement ≥70%). Expects attributed greenhouse irrigation water as a highly important source of contamination with human pathogens. Accordingly, testing of irrigation water for human pathogens was considered to be a valuable tool in controlling contamination in the greenhouse. According to this expert panel, people may occasionally introduce pathogens into the greenhouse. Hand washing and footwear were ranked the most effective in preventing contamination from employees and visitors. The majority of experts believed the presence of human pathogens in the greenhouse environment presented an important source of contamination for edible tomato fruits. Experts also agreed that livestock and poultry operations should be at least 250 feet away from the greenhouse. Although any animal intrusion was considered a high-extreme food safety risk-rodents were ranked the highest, and cats the lowest. Employee hygiene, mode of irrigation, equipment sanitation was ranked the most important management practice in prevention of contamination with human pathogens.

Bananas (Musa spp.) are subject to a number of diseases that are difficult to diagnose early in development when control measures are most likely to be successful. Rapidly spreading new diseases, such as Xanthomonas wilt present unique diagnostic challenges. Surveys conducted in East and West Africa documented the lack of sufficient equipment, supplies, reference materials and training in the majority of plant pathology laboratories charged with disease diagnoses. To begin to address these issues, the International Plant Diagnostic Network (IPDN) was established in East and West Africa in 2006, through the Integrated Pest Management Collaborative Research Support Program (IPM CRSP). The IPDN is a diagnostic, communication and data network, modeled in part on the United States National Plant Diagnostic Network. Software for digital imaging and diagnosis and information management provides a platform for enhanced diagnosis and communication amongst clinicians and their clientele. Improved diagnostics tools and protocols were also developed and tested, including a PCR assay for Xanthomonas wilt. Training programs were conducted in Benin in 2006, Kenya and the United States of America in 2007, and Uganda and Mali in 2008, to enhance technical capacity amongst diagnosticians in East and West Africa. Initiatives such as IPDN can benefit by collaboration with other similar internet-based initiatives in Africa. One such activity is the East Africa Phytosanitary Information Committee (EAPIC). EAPIC is linked to the Food and Agricultural Organization's International Plant Portal to provide the official national plant protection organization posting of plant pests for each respective country, which now includes Kenya, Tanzania, Uganda and Zambia. The plant pest list will serve as a foundation from which to develop harmonized border inspection protocols, which in turn support capacity building efforts in plant pest survey, identification and communication systems, such as IPDN.

Glucosinolate-producing cover crops are being marketed as biofumigants to reduce soil-borne diseases and increase yields. ‘Caliente 119’ (Brassica juncea and Sinapis alba), ‘Caliente 99’ and ‘Caliente 61’ (B. juncea) and ‘Nemat’ (Eruca sativa) were tested for their effects on growth, yield and incidence of anthracnose, blossom end rot and minor fruit rots of processing tomatoes at OARDC research stations in Fremont and Wooster, in 2006. Spring-seeded ‘Caliente 119’, ‘Caliente 99’ and ‘Caliente 61’ produced similar amounts of biomass, significantly higher than that produced by ‘Nemat’ in both locations. ‘Caliente 119’, ‘Caliente 99’ and ‘Caliente 61’ were significantly taller than ‘Nemat’ plants, but ‘Nemat’ population density was higher than recorded for the mustard varieties in Fremont. There were no differences among cover crops in germination in Wooster. In Fremont, there were no significant differences between plots with or without cover crops in tomato growth parameters, total or marketable yield, or percentage of fruits with anthracnose or blossom end rot. In Wooster, tomatoes following ‘Caliente 119’, ‘Caliente 61’ or ‘Nemat’ were shorter than plants not following a cover crop. Tomato plant width and number of leaves per plant were less in tomatoes following any cover crop than the non-cover control. Total fruit yield was lower in tomatoes following ‘Caliente 119’, ‘Caliente 99’ and ‘Caliente 61’ than the control, but there were no differences in marketable yield or yield of fruit with anthracnose. Minor fruit rots were lower in tomatoes following ‘Caliente 99’ and ‘Nemat’ than the control in Fremont. However, minor fruit rots were higher in tomatoes following ‘Nemat’ than the control in Wooster.

The effects of different strategies for transition to organic tomato production on timber rot (Sclerotinia sclerotiorum), early blight (Alternaria solani) and Septoria leaf spot (Septoria lycopersici) incidence and severity, soil chemistry and yield were studied. The four cropping strategies considered were 1) low input cover crop/fallow, 2) low input perennial mixed hay, 3) moderate input field vegetables, and 4) high input extended season vegetables under high tunnels. Each was considered with and without compost applications. Each cropping strategy was carried out for 3 years, and then all plots were cropped to fresh market tomato, cultivars Florida 47 and Mountain Spring in the fourth year. Annual applications of composted dairy manure during the 3-year transition and prior to tomato planting resulted in significantly less timber rot and early blight in high tunnels, and Septoria leaf spot in open field plots under the mixed hay transition strategy, than in the non-amended plots. Tomatoes in the mixed hay transition strategy tended to have less Septoria leaf spot than those in the open fallow and vegetable transitions. Septoria leaf spot was significantly higher in Mountain Spring than in Florida 47 in open-field plots. Transition strategy generally did not affect soil fertility, but, in all cases, compost amendment significantly increased soil C, N and other nutrients. Compost amendment in the each cropping strategy significantly increased total and marketable yield for green to pink and light red to red maturity stages of both cultivars. The high-tunnel vegetable cropping strategy significantly increased to total and marketable yield for both cultivars. There were no significant differences among cultivars in the total and marketable yield.

A pilot project focused on IPM for home gardens was conducted by establishing demonstration trials at public garden sites in three cities (Wooster, Stow and Twinsburg) in northeastern Ohio, USA. Three strategies for disease and insect pest management were compared: 1) “low maintenance” with emphasis on cultural practices, a management style common among gardeners lacking time for laborintensive gardening; 2) “integrated biorational”, utilizing integrated cultural and biorational tactics, with biorational pesticides applied only when needed; and 3) “traditional IPM”, utilizing cultural tactics and conventional synthetic chemicals. Tomatoes, zucchini squash, snap beans and collards were planted in each garden. Early blight (Alternaria solani) and Septoria leaf spot (Septoria lycopersici) were the principal foliar diseases observed in tomatoes in all three sites; disease pressure was low-moderate. Tomatoes in the traditional IPM and integrated biorational systems had less foliar disease throughout the season, as measured by the Area Under the Disease Progress Curve (AUDPC), and at the end of the growing season than the low maintenance system in all three sites. The traditional IPM system yielded the most total fruit yield or percentage of marketable fruit and significantly fewer fruits with anthracnose, hornworm and stinkbug damage. There were no significant differences between strategies in percentage of fruits with blossom end rot for the three sites.