Grant Information
| Knowledge Area | Subject of Investigation | Field of Science | Percent |
|---|---|---|---|
| 216 - Integrated Pest Management Systems | 1499 - Vegetables, general/other | 1160 - Pathology | 80% |
| 216 - Integrated Pest Management Systems | 999 - Citrus, general/other | 1160 - Pathology | 20% |
Florida ranks first in the U.S. in the farmgate sales value for fresh market tomatoes, bell peppers, squash, and watermelon and first in the value of production of oranges, grapefruit, and tangerines (Agricultural Marketing Resource Center, 2010). Florida growers receive more than US $500 million in sales of tomato, $200 million in bell pepper, and $150 million in cucurbits (watermelon, cantaloupe, cucumber, and squash). Citrus is a $1 billion industry. Southwest Florida is a leading producer of citrus and vegetables including pepper, watermelon, cantaloupe, squash, corn, cucumber, potato, tomato, and snap bean. A large transplant industry for vegetables is located in the region. Additionally, there are ornamental and palm nurseries, herb producers, organic growers, and various specialty crops. This wide diversity of crop species can be subjected to a number of limiting plant diseases, most of which are favored by Floridas subtropical climate of warm and wet environmental conditions for rapid disease development. Additionally, Florida crops are exceptionally at risk because of the frequent introductions of exotic pests, including plant pathogens. Plant diseases can severely and adversely affect production of all of these crops. Documented disease outbreaks caused 100% plant loss in watermelon and tomato caused by watermelon vine decline (Squash vein yellowing virus; Adkins et al,. 2007) and late blight (Phytophthora infestans), respectively. Losses incurred by diseases can impact productivity by 10-50% in any given year. Currently, the citrus industry is facing one of the most devastating diseases of citrus, Huanglongbing (HLB) a.k.a. greening disease (Candidatus Liberibacter asiaticus), vectored by the Asian citrus psyllid, which causes tree decline, lost productivity due to reduced yields and quality, and ultimately tree death (Bove, 2006; de Graca, 1991). Another disease introduced in the 1990s, and now endemic to Florida citrus despite a massive eradication program, is citrus canker caused by the bacterial pathogen, Xanthomonas citri subsp. citri. Citrus canker can cause severe yield losses due to fruit blemishes and premature fruit drop. The introduction of exotic pests to Florida creates challenging situations to the ecosystem and agriculture. Although the potential exists that an exotic pest can devastate a particular host and entire industry, at the very least, growers may have to substantially change their management practices and increase inputs to include disease control measures for an exotic pathogen. Additionally, established pathogen populations can shift and become increasingly problematic to manage, for example, a genetic shift may occur in the pathogen which then becomes insensitive to fungicide active ingredient
1. Spatial and Temporal Incidence of Ca. Liberibacter in Citrus and Psyllids Detected Using Real-time PCR. 2. We are collaborating with researchers to evaluate lines of cucurbits for resistance to Squash vein yellowing virus causing watermelon vine decline; the use of resistant pollinizers and insecticides to slow the rate of the virus spread (Kousik et al., 2009); and use of systemic acquired resistance inducers to slow the rate and severity of the watermelon vine decline in field studies. All trials are complete block, randomized with four replications of each treatment. In the fall and spring seasons, seedlings are transplanted to field as described above and receive various treatments . Disease severity (percentage symptomatic tissue) or disease incidence (percentage of plants showing incidence) will be assessed throughout the season at 7- to 14- day inverals. The differences will be examined between means by Least Significant Difference (LSD) using SAS. 3. In vitro, In vivo, and field testing to evaluate efficacy for novel or other compounds Bacterial suspensions will be prepared by suspending 24-h cultures in a sterile phosphate-buffered saline (Leben et al. 1968). For in vitro assays, the suspensions will be adjusted to an absorbance of 0.3 at 600 nm (5x108 CFU/ml). Bacterial suspensions will be combined with the chemical suspensions in test tubes at a ratio of 1:1 (vol:vol). Test tubes will be placed on a shaker platform. Following shaking, suspensions will be filtered with a sterile Whatman no. 1 filter paper. The filtrate will serially be diluted and an aliquot of appropriate dilutions will be plated on media in petri plates. There will be three plates per dilution series. Plates will be incubated at 28C for 3 days. Colonies will be counted and differences among treatments assessed using SAS.
Target Audience
The target audience were growers, crop consultants, county agents, extension and research faculty, agroindustry, regulators, and Florida residents. Since most commercial vegetables growers employ a scouting service, our direct contact is typically through these professionally hired scouting service.
Changes / Problems
Nothing Reported
Training & Professional Development
Scouting for diseases on cucurbits Statewide in-service training and grower meeting Citrus Squeezer: Citrus Black Spot Presentation Citrus Squeezer, Immokalee Citrus Canker Management Presentation Ft Pierce Basics of Plant Pathology Master Gardener training: Charlotte County Basics of Plant Pathology Master Gardener training, Collier County Spring vegetable field day SWFREC, Immokalee, FL Vegetable grower meeting: late blight SWFREC, Immokalee, FL Novel product use in tomato disease management Homestead, FL Ex-officio member of the Vegetable Advisory Committee SWFREC
Dissemination Streams
Partnered with extension agents, consultants, agrochemical and associated industry personnel, and extension faculty in visits to clientelle Presented program outcomes in presentations at grower meetings Provided disease diagnostics and integrated management recommendations through both the HLB Diagnostic Lab and Florida Extension Plant Disease Diagnostic Clinic Provided printed and on-line educational materials through EDIS, trial reports, trade journal articles, PowerPoint presentations, disease identification cards, and other materials Served as a resource to news reporters Provided yearlyIn-Service Training Conducted on-site demonstration and disease management trials Conducted demonstration trials at SWFREC and disseminate the results in written reports, presentations, and on the website Updated fungicide and management recommendations in EDIS documents and other materials Provided written and verbal interpretation of management strategies to growers, extension agents, industry, consultants, and other interested parties Tested products and programs(fungicides, bactericides, chemical, experimental compounds, SAR, and biological control agents)in field trials.
Next Reporting Steps
Nothing Reported