William T. (Billy) Crow
Landscape Nematologist, University of Florida
Entomology and Nematology Dept.
P.O. Box 110620
Building 970, Natural Area Dr.
Gainesville, FL 32611-0210
(352) 273-3941
FAX (352) 392-0190
E-mail
Position
Extension (70%), Research (25%), Teaching (5%)
Extension Responsibilities
This position centers on the diagnosis and management of plant-parasitic nematodes affecting turfgrasses, ornamental plants, and residential landscapes. As an extension educator, my major role is preparation of training materials and presentation of training programs for use by county extension faculty and volunteers, and commodity group clientele. These training materials include fact sheets, slide presentations, demonstration instructions, and for-sale publications. Training programs include in-service training for county extension agents, training for master gardeners, clientele training organized by extension faculty and by commodity groups, and participation in field days. I also manage the University of Florida Nematode Assay Lab, which provides diagnoses of nematode disorders of plants for extension personnel and clientele.
Teaching Responsibilities
My goals in teaching are to provide students with the tools they need to solve the problems and challenges they will face, and to give them practice doing so. As a mentor for graduate students, I give the student a rough outline of what needs to be done, and then allow them to put the substance on the skeleton. When the student faces difficulties, I point them in the right direction and give them any help they need, but allow them to attempt to solve the problem before getting involved directly. In the classroom, I generally use lots of case studies from real-life situations to give students practice in putting together the knowledge they have. We also go on lots of field trips to give students first-hand experience in applied nematology.
Nematode diagnosis: 2 Credits. Spring and Fall semesters. Hands-on graduate course developed to train students in diagnosis of nematode disorders of plants. This course is a requirement for students in the Doctor of Plant Medicine program, but is available to others as space is available. NEM6942
Field Plant Nematology: 2 Credits. Spring semesters. This course is designed to expose students to current applied research being conducted in Nematology and related subjects, and to familiarize the students with agricultural production techniques used by the different agricultural sectors in Florida. The course entails visits to University of Florida research sites around the state, as well as USDA and industry facilities. NEM6708
Research Responsibilities
The green industry (turf and ornamentals) generates >$10 billion for Florida’s economy annually. Plant-parasitic nematodes are a major limiting factor to the production and maintenance of turf and ornamental plants in this state. As an extension specialist, I need to properly diagnose plant disorders caused by nematodes, and then recommend management options to treat these disorders. My research program is designed to generate the information necessary to better conduct my extension duties.
To properly diagnose nematode problems, it is essential to correctly identify plant-parasitic nematodes and to know how much damage they cause. We have recently identified the two most common species of stubby-root nematodes associated with turf in Florida (Paratrichodorus minor and Trichodorus obtusus), and discovered ways to readily distinguish the two in a diagnostic setting. We have compared the virulence of these two nematodes on common turf species and determined the "action threshold" population density when treatment is recommended for each species. We also have identified ways to easily distinguish in diagnostic settings the several genera of spiral (Helicotylenchus, Peltamigratus, and Scutellonema) nematodes that feed on turf grasses in Florida.
As new plant species are introduced into Florida landscapes, it is important to identify potential pest problems that might occur. Seashore paspalum is a new species of turfgrass that is being used on lawns and golf courses in Florida. We recently determined that this grass is susceptible to sting (Belonolaimus longicaudatus) and lance (Hoplolaimus galeatus) nematodes. Because seashore paspalum has high salt tolerance and is used in saline environments, we studied the effects of salinity on plant-parasitic nematodes affecting this grass. We determined that irrigation with high salinity water is a potential management tool for nematodes affecting seashore paspalum turf. We have screened numerous perennial landscape plants for resistance to the four most common species of root-knot nematodes (Meloidogyne incognita, M. arenaria, M. javanica, and M. mayaguensis) that attack landscape plants in Florida. We identified two, firespike (Odontonema cuspidatum) and ‘Gold Dust’ croton (Codiaeum variegatum), that are immune to all four root-knot nematode species. This information is now being used to make recommendations for alternative planting in root-knot nematode infested landscapes.
Recently, water quality and quantity have come to the forefront of environmental policy in Florida. In addition to the economic losses and quality reductions resulting from nematode damage to turf, there are also negative environmental impacts that may result. Our studies have shown that sting nematode increases the potential for nitrate leaching in bermudagrass, decreases the effectiveness of fertilizer applied, and greatly reduces drought stress. Therefore, nematode control on turf may reduce groundwater contamination and water usage.
Fenamiphos, has been the predominant nematicide used on turfgrasses for the past 30 years. However, this nematicide will no longer be manufactured after May 2007. This has created a great need for development of new nematode management strategies that are efficient, economical, and environmentally sound. We are actively pursuing numerous strategies including chemical control, biological control, and enhancing plant tolerance. We have been evaluating >20 potential nematode management products each year. In addition to searching for effective new products for nematode management on turf and ornamentals we are providing a valuable service as an independent product-testing provider. Many of the products being marketed to the turf and ornamental industries have not undergone rigorous testing in the field. Without having worked with these products, it is impossible to give recommendations to our extension clientele on what to expect if these products are used.
Staff
Mr. Frank Woods, Senior Biologist
Mr. Matt Coon, OPS
Graduate Students
Mr. Pauric McGroary (M.S. student)