Increasing use of sustainable plants in production and landscape design

Increasing use of sustainable plants in production and landscape design

Summary

PEST – RESISTANT PLANT SELECTION SOFTWARE: The pest resistant plant database that is being developed for this SARE grant is now in a beta version that is ready for distribution to Extension agents and specialists and Master Gardeners in the four cooperating states that are part of this grant (GA, FL, TN, MS). To facilitate distribution to extension agents, specialists and master gardeners in the cooperating states, an online download tool has been created and tested on a small scale.
Additionally, the beta version of the software has been presented to over 250 green industry professionals in the Southeast and nationally at several professional meetings including: the annual GA/FL Green Industry Update, the Entomological Society of America Master Gardener symposium and the Georgia State Botanical Garden Native Plant Symposium.
LANDSCAPE PEST MANAGEMENT SURVEY:Data collection for the 4-page survey from landscape and grounds management professionals was concluded in September 2007. Responses, which were tabulated and assessed for correct data entry into the spreadsheet, yielded 328 usable surveys that are presently subject to statistical analysis.
PLANT EVALUATION FOR PEST RESISTANT CULTIVAR SELECTION: Results of field and greenhouse experiments evaluating St. Augustinegrass cultivars determined that Raleigh was most heavily infested while Floratam and Floralawn were least infested by the southern chinch bug in central GA. Antibiosis among 25 Paspalum taxa to fall armyworm was identified. Warm season turf selections of centipedegrass, bermudagrass, St. Augustinegrass, and zoysiagrass were evaluated for tolerance to adult two lined spittlebug (Prosapia bicincta Say) feeding in choice and no- choice experiments, and for their ability to support nymphal development (antibiosis potential). Among 133 selections evaluated for response to the two lined spittlebug, several showed evidence of potential antibiosis and/or improved tolerance over commercially available cultivars.

Objectives/Performance Targets

This program will research, develop and deliver a mutually conceived plant information and resource database that will simultaneously encourage the demand, production and ultimate use of low-input, horticulturally-desirable plants in southeastern landscapes. Abundant research has been conducted to identify pest-resistant and other lower-input plants. That information, however, is unsystematically distributed and, therefore, not readily accessible. Additionally, sources of low-input and pest resistant plant material, when requested by homeowners or landscape architects and designers, are often unavailable or difficult to locate. We engage Green Industry professionals with our multi-state, interdisciplinary research and extension team in the development of a multi-pronged plan to 1) identify optimal plant material (from both low-input and horticultural aspects), 2) provide a tool to facilitate the location of these optimal plants and 3) educate Green Industry professionals on the feasibility and technical aspects of sustainable landscapes. Our goal is to enhance the likelihood that low-input plants will be specified in landscape design, thereby stimulating and expediting the production and availability of such materials.

Accomplishments/Milestones

PEST-RESISTANT PLANT SELECTION SOFTWARE:
The pest resistant plant database that is being developed for this SARE grant is now in a beta version that is ready for distribution to Extension agents and specialists and Master Gardeners in the four cooperating states that are part of this grant (GA, FL, TN, MS). In the past year, we have finalized the descriptive fields to be used in the database (bringing the total to over 500). These searchable characteristic were chosen to best represent the pest resistance level and describe the spectrum of pests and pest damage that can be expected for any particular plant. Two unique printable reports were created to communicate this information and are available as a tool within the software. These reports are designed to allow customized reports of pest resistance and pest problems for each unique plant list of pest resistant plant selected by the user. A graphical interface was developed to ease the learning curve of the user and to emphasize the beauty of pest resistant and native plants, furthering the idea that pest resistant and native do not equate to dull or boring. To facilitate distribution to extension agents, specialists and master gardeners in the cooperating states, an online download tool has been created and tested on a small scale.
Additionally, the beta version of the software has been presented to over 250 green industry professionals in the Southeast and nationally at several professional meetings including: the annual GA/FL Green Industry Update, the Entomological Society of America Master Gardener symposium and the Georgia State Botanical Garden Native Plant Symposium. At each of these events we have informally gathered input to improve the software’s usability and usefulness to a wide ranging audience. During the next phase of this project, we will distribute the software to Green Industry professionals and Extension faculty via a web downloadable executable file from the web. We will gather formalized feed back from recipients and incorporate their plant notes and comments into a final version of our software that will be made available, free-of-charge to University faculty and staff and Master Gardeners in the four cooperating states listed above.
LANDSCAPE MANAGEMENT SURVEY: Data collection for the 4-page survey from landscape and grounds management professionals was concluded in September 2007. Responses, which were tabulated and assessed for correct data entry into the spreadsheet, yielded 328 usable surveys that are presently subject to statistical analysis.
PLANT EVALUATION FOR PEST RESISTANT CULTIVAR SELECTION: Results of field and greenhouse experiments evaluating St. Augustinegrass cultivars determined that Raleigh was most heavily infested while Floratam and Floralawn were least infested by the southern chinch bug in central GA. Experimental lines tested did not exceed resistance in Floratam, but were not as susceptible as others, e.g., Raleigh. Quality measurements indicate a range in aesthetic response to SCB densities. Predators of chinch bugs were well represented in plots.

Antibiosis among 25 Paspalum taxa to fall armyworm was identified. Larvae failed to survive to 8d on 5 of the Paspalum spp. accessions, including PI-282807 (P. macrophyllum), PI-310146 (P. notatum), PI-422024 (P. notatum var. saurae), PI-462290 (P. plicatulum) and PI-462298 (P. quadrifarium). Paspalum selections with the lowest larval weights, suggesting some degree of antibiosis, included PI-286486 (P. thunbergii), PI-404449 (P. ionanthum), PI-404465 (P. minus), PI-419929 (P. dilatatum), PI-209983 (P. nicorae), ‘Sea Spray’ and ‘Aloha.’ The lowest pupal weights were observed among Paspalum spp. accessions, including PI-304147 (P. pubiflorum), PI-404643 (P. conjugatum), PI-209983 (P. nicorae), PI-419929 (P. dilatatum) and PI-477100 (P. dilatatum subsp. flavescens). Extended days to develop to pupal stage were observed for PI-209983 (P. nicorae), PI-404643 (P. conjugatum), PI-304147 (P. pubiflorum), PI-419929 (P. dilatatum), PI-477100 (P. dilatatum subsp. flavescens), 03-539-31, ‘Aloha’ and ‘Sea Isle Supreme.’

Warm season turf selections of centipedegrass, bermudagrass, St. Augustinegrass, and zoysiagrass were evaluated for tolerance to adult two lined spittlebug (Prosapia bicincta Say) feeding in choice and no- choice experiments, and for their ability to support nymphal development (antibiosis potential). Among 133 selections evaluated for response to the two lined spittlebug, several showed evidence of potential antibiosis and/or improved tolerance over commercially available cultivars. Most of the centipedegrass germplasm evaluated was susceptible to the spittlebug. Some potential antibiosis among Chinese centipedegrass introductions was identified, and there was a gradient in the ability of the different grasses to tolerate spittlebug feeding. Among the centipedegrasses evaluated, fewest nymphs developed on TC 341, TC 379, TC 399, TC 422 and E. cilliaris. The bermudagrasses 00-23 and 00-28 and the St. Augustinegrasses T638 and Mercedes failed to support development in either of the two developmental trials conducted. In a laboratory trial, the fewest nymphs developed on St. Augustinegrass. Among centipedegrasses, the least damage was visible on TC 441, TC 341, TC 358, TC 342, TC 344, TC 390, TC 438, TC 362, TC 347 and TC 346 in no- choice trials. In choice trials, however, the least damaged centipedgrasses were TC 324, 325, 326 and 338 and TC 358 and 359. The most tolerant bermudagrasses were 00-23, 03-14, and 03-15.

Impacts and Contributions/Outcomes

Optimal plant material selection:
In Georgia more than 200 plant cultivars have been evaluated for optimal performance, invasive tendencies, and pest resistance. Additional evaluations are on-going with results expected to add to the optimal plant locator software being developed.

Provision of a tool to facilitate the location of optimal plants:
The pest resistant plant database that is being developed for this SARE grant is now in a beta version that is ready for distribution to Extension agents and specialists and Master Gardeners in the four cooperating states that are part of this grant (GA, FL, TN, MS). In the past year, we have finalized the descriptive fields to be used in the database (bringing the total to over 500). This tool will permit selection of optimal plant material for various landscape uses and integrate directly with software typically used in landscape design.

Educate Green Industry professionals on the feasibility and technical aspects of sustainable landscape design:
The beta version of the software has been presented to over 250 green industry professionals in the Southeast and nationally at several professional meetings including: the annual GA/FL Green Industry Update, the Entomological Society of America Master Gardener symposium and the Georgia State Botanical Garden Native Plant Symposium. At each of these events we have informally gathered input to improve the software’s usability and usefulness to a wide ranging audience. Ongoing project results were delivered to audiences at the 2008 Georgia Green Industry Association sponsored Wintergreen and the Kentucky Nursery and Landscape Annual Conference.

Collaborators: