Research Focal Areas

Introduction Faculty and students have academic freedom to choose research topics. Topics are influenced, however, by the RI Agricultural Experiment Station and by external granting agencies. In developing a strategic plan for the department, we have agreed to recognize three principle focal areas which characterize much of our research. These are Sustainable Landscapes, Arthropod Vectors of Human Disease, and Invasive Species.

Sustainable Landscapes

Plant Development

We are developing plants that are economical to grow and maintain—in home, work, and recreational plantings—and that require minimal water, fertilizer, energy, or pesticides. We select, breed or change plants through biotechnology. Our primary focus is on ornamental horticulture and turfgrasses, which are important to RI agriculture. We use genomics and transgenics while remaining sensitive to public concerns about biotechnology.

Trees and Shrubs Plant development for trees and shrubs aims to increase the diversity of sustainable tree and shrub taxa available to the RI and NE nursery and landscape industries. Our research emphasizes increasing new ornamental plant germplasm for use in New England landscapes: specifically we concentrate on plant materials that may be substituted for pest-prone taxa. For example, we are working on salt-tolerant conifers suitable for replacement of Japanese black pines dying along the RI seaboard. We are also studying possible replacements for insect-susceptible Canadian hemlocks. We also have five new shrub taxa (RI natives) under evaluation for release and possible patent. We collaborate with the USDA National Arboretum, the Landscape Plant Development Center, and J.F. Schmidt & Sons Nursery,. the Rhode Island Nursery and Landscape Association, New England Nursery Association, and the Horticulture Research Institute.

Turfgrasses The goal of the URI turfgrass program is to increase grass tolerance to stress—from mowing, wear, dryness, insects and diseases, and salt—thereby reducing costs and environmental effects from fertilizers, pesticides, and fossil fuels. We emphasize development of varieties adapted to New England; current focus is on bentgrass (Agrostis spp.) and fine leaf fescues (Festuca spp.). We also evaluate the local fitness of turfgrass varieties developed elsewhere.

We are working with private companies on transgenic transformation of turfgrasses, reducing the time required for traditional breeding; we also continue to use traditional breeding and germplasm screening methods. We are also interested in turfgrass management; the aim is to decrease turf effects on the environment

Plant Management

Trees and Shrubs We are at work to clone and propagate trees and shrubs which use less water and chemicals. We are studying ways to treat nursery fertilizer and chemical runoff using ornamental plant biofiltration systems that produce a saleable crop. We are evaluating loss of nutrients and pesticides through above-ground and pot-in-pot production systems, using a new total-capture irrigation system and biofilter systems. Finally, we will continue efforts to reduce the impact of deer browsing and antler-rubbing in nurseries and landscapes.

Pest Management

Trees and Shrubs Research on plant pathology in trees and shrubs is derived from both local needs (eg. Phytopththora on Rhododendrons) and national problems (eg. Sudden Oak Death, below).

Phytopththora. Local Rhododendrons—a major revenue source for nurseries—are highly susceptible to Phytopththora, which causes significant annual losses. Our focus is to identify and quantify resistance to this disease in available germplasm.

Apple Replant Disease. We are investigating the possibility that "apple replant disease," a problem commonly seen in commercial apples, occurs on crabapples. Using our East Farm crabapple orchard, we are determining the severity of this disease on crabapples; we are looking for management strategies for landscapers and homeowners wishing to grow crabapples.

Sudden Oak Death. A new fungus species is killing oak trees in California. The fungus has been found since on many under-story shrubs, forest trees, and woody nursery plants. Nursery crops moved about the country may vector the disease, potentially devastating oak forests and urban/landscape plantings throughout North America. Despite severe quarantines against movement from affected areas in California, the pathogen has been found killing trees in Oregon (a major source of plant materials for the RI Green industry). The USDA recently funded a cooperative project between URI (Dr. Englander) and the USDA-ARS Plant Quarantine facility in Ft. Detrick MD to develop essential knowledge about the environmental and biological parameters of this pathogen.

Turfgrasses Our turfgrass pest management focuses on pests of both golf courses and sod farms, in response to local and national problems. Our overall goal is to manage pests economically, with minimal impact on the environment.

Research focuses on stress-induced pathogens and on integrated management strategies to lessen disease pressure. We study Cephalosporium, Leptosphaerulina, and other fungal species. We are exploring the diversity and management of Nematodes, a perennial stress-related pathogen on turf in New England. We also investigagte the biology and control of bacterial blight of annual bluegrass, an emerging disease, and diseases of ornamental grasses, which are increasingly common in the Northeast. Fungicide efficacy trials provide current information on specific fungicides and fungicide resistance in Rhode Island.

The goal of the turfgrass insect research program is to continue to develop biological (entomopathogenic nematodes, bacteria) and least-toxic (pheromone mating disruption) methods for control of major turfgrass insect pests in the Northeast.

Arthropod Vectors of Human Disease

Diseases transmitted by ticks and mosquitoes are a significant concern in Rhode Island and much of the northeast. Reforestation and demographic shifts towards the suburbs facilitate serious tick-transmitted infections. The physical geography of the region supports diverse and abundant mosquito populations, many of which carry diseases. The recent introduction of West Nile virus into the northeast shows how vulnerable the region is to threats from arthropod-associated human and animal pathogens.

The current research capacity for responding to vector-borne disease threats in Rhode Island is largely within the Department's Center for Vector-Borne Disease. The Center's research focus includes 1) enhancing disease and risk surveillance; 2) improving diagnostic tools and capacity; 3) elucidating vector/microbe and vector/host interactions for the purpose of disease prevention and control; and 4) developing, implementing, and evaluating community-based disease prevention strategies.

Ticks

We focus on tick biology, ecology, and control. Specific research goals are to

Mosquitoes

Our focus is on mosquito pathology, ecology, and surveillance and management of mosquito-borne diseases. The RI Mosquito Abatement Coordinator, Department of Environmental Management (Dr. Gettman) is an adjunct member of our department. Primary research goals include to

Invasive Species

Non-native plants and animals that are introduced into North America typically come without the natural enemies that keep them in check in their native habitats. Freed from natural controls, alien species reproduce and spread. We are addressing this issue by attempting to reduce the risk from purposeful plant introductions, and by working on biological control of select insect and weed problems.

Identification and Replacement of Invasive Ornamentals

Of the thousands of species of exotic plants that were introduced and distributed in this country for horticultural or agronomic uses over the past 300 years, several species are now widely regarded as pests. Well-known examples include kudzu, crabgrass, dandelion, barberry, and purple loosestrife. Some important ornamental plants (Norway maple, winged euonymous, Korean dogwood) have invasive tendencies, which may present problems in minimally managed landscapes. Our research focus is to identify invasive species and select, evaluate, and promote alternative species suitable for the nursery and landscape industries.

Our research and outreach goals in this program are to

Biological Control of Invasive Species

Of ~ 1,700 introduced insects in this country, over half are identified as pests. The 300 species of invasive plants in North America have already infested 100 million acres and infest another 3 million acres per year (about 4.5 times the land area of R.I.). Combined with the other exotic invasive animals (such as zebra mussels) these invasive species cause ~$123 billion in damages annually in the USA. In many cases these problems can be solved by "reacquainting" these "pests" with effective natural enemies in a deliberate process called "Classical Biological Control."

Our USDA-approved primary quarantine laboratory—the only university quarantinelab in the Northeast— allows us to import and study potential biological control agents that do not exist elsewhere in North America. We concentrate on invasive insects and plants, particularly those of consequence to landscape plants in the Northeast. We are currently working on birch leafminer, hemlock woolly adelgid, lily leaf beetle, purple loosestrife, Cypress spurge, and Phragmites australis (common reed). The goal of this research is to provide permanent control of key insect and weed pests and in the process to advance the science of biological control.