Recipient Organization
UNIVERSITY OF FLORIDA
G022 MCCARTY HALL
GAINESVILLE,FL 32611
Performing Department
AGRI RES & ED CENTER, APOPKA
Non Technical Summary
Managing plant disease is an important sub-component of plant protection for vegetable and ornamental production. As with insects, management of plant diseases present unique situations and opportunities, so disease management research is an important goal. The objective of this research is to explore and develop safe and effective disease management methods for vegetable and ornamental production in order to reduce impacts from diseases and reduce pesticide use. Information gained would also apply to horticultural crop production throughout Florida, southeastern U.S. and the Caribbean. Florida's horticultural industry is currently responding to new pests, foreign competition, expanding urbanization, environmental concerns, and other economic and social factors by shifting to different crop production systems and product diversification. The shift has been to novel, higher-quality, branded, and value-added products. Examples are ethnic vegetables, vine-ripened tomatoes
and branded fruits such as strawberries, miniature vegetables, ripe products such as colored pepper, Cuban squash, and herbs such as cilantro (coriander). Organic vegetable production is also increasing. Nurserymen are planting new landscape cultivars and species and producing larger, higher quality plants suitable for 'instant landscapes'. These trends are creating new pest and production problems, so new approaches to production, plant protection are required.
Animal Health Component
75%
Research Effort Categories
Basic
25%
Applied
75%
Developmental
(N/A)
Goals / Objectives
To develop disease management strategies to protect vegetables and ornamental plants from diseases or lessen their impact thereby increasing the profitability of production in an environmentally sound manner. Specific objectives include: 1. Describe and identify important diseases, pathogens, and disorders and study the interactions between plants and their pathogens that result in disease damage, including the evaluation, modification, and development of detection and identification techniques for plant pathogens. 2. Study the life systems of disease-producing organisms and plant production systems and identify important factors which can be manipulated or altered to avoid or reduce the impacts of plant diseases. 3. Develop and evaluate disease management tactics which are economical and environmentally-acceptable and which minimize disease impacts and enhance economic return.
Project Methods
In many cases, causal agents will be unknown and must be elucidated by isolation, identification and pathogenicity tests. Methods and procedures will be diverse and determined by the specific problem, but will generally follow approaches standard to plant pathology research for viruses, bacteria and fungi. For example, fungi would be isolated from diseased tissue, grown in axenic culture, and identified by microscopic examination. In many cases, molecular techniques such as PCR, biochemical profiles, and DNA fingerprinting and hybridization techniques would be employed for identification and detection. Plants would be inoculated with the suspect pathogen and its ability to produce the original disease confirmed. When appropriate, the mechanisms and occurrence of important impacts and losses will be documented (for example seasonal occurrence, disease intensity, spacial distribution), and economically important damage thresholds determined. Knowledge of the life systems
of pathogens is essential to determine which production activities are conducive to disease and which can be manipulated or revised to deter disease occurrence or slow development. Similar knowledge is needed to formulate pesticide-based approaches particularly in regard to timing and placement. The biology of pathogens will be studied in the laboratory to determine key variables such temperature and pH, basic reproductive and dissemination strategies, and survivability and persistence capabilities(for example, persistence in soil, seeds, or plant debris) would be investigated. In greenhouses or controlled-environments, factors such as temperature and leaf wetness periods that influence infection and disease development will be determined, then verified in field experiments. In the field, dissemination of the pathogen and the influence of weather on disease development would also be examined. Environmental monitoring, spore trapping, and monitoring of disease development and progress
by sampling or scouting are examples of methods used in this phase of research. Effective fungicides and bactericides will be identified through lab, greenhouse and field testing sometimes using potted plants or detached leaves. Optimum rates, application methods, and frequencies will be determined through field testing in small, replicated plots or in larger plots with grower participation. Cultural activities greatly influence the success or failure of disease control and are a key part of plant disease management. With knowledge gained, interactions of important cultural activities can be postulated and verified in field experiments. Development of monitoring and scouting methods and approaches to these tasks may be appropriate in many instances. Fungicide programs alone will not provide acceptable results unless well-integrated with cultural practices that avoid disease or are detrimental to disease progress. However, in the case of horticultural crops, the testing and labeling of
fungicides or biologically-based pesticides will be needed, so cooperative work with chemical companies and IR-4 will likely be an important component of this project.