Search Results
This research was conducted to determine if application of 1,3-dichloropropene (1,3-D) could reduce turfgrass water requirements in soil infested with sting nematodes (Belonolaimus longicaudatus Rau). The effects of 1,3-D and fenamiphos were evaluated on quality and persistence of `Tifway 419' bermudagrass (Cynodon dactylon × C. transvaalensis Burtt-Davy) subjected to drought or deficit irrigation. The research consisted of two greenhouse studies in 2002 and 2003 where irrigation was either withheld or applied in deficit quantities, and one field study in 2003 where irrigation was withheld. In general, 1,3-D-treated turf maintained up to 40% higher quality during drought than other treatments and had up to 27% less leaf wilting. As drought severity increased, 1,3-D treatments had better spectral reflectance values, indicating better physiological functioning under stress. Results of this research suggest that application of 1,3-D in sting nematode-infested soils may increase bermudagrass drought survival.
Kentucky bluegrass (Poa pratensis L.) cultivars are often blended to incorporate diverse characteristics. Factors that may contribute to the actual cultivar composition have not been evaluated. Through the use of DNA markers, individual plants in blended stands can be identified. This study evaluated changes in cultivar composition of `Blacksburg', `Midnight', and `Unique' Kentucky bluegrass blends. Characteristics such as seed size, seed moisture content, percent germination, and seedling development did not affect the initial composition of blends at time of seeding. DNA markers were used to demonstrate how the composition of a blended `Blacksburg', `Midnight', and `Unique' turf changed during the first growing season following establishment. The composition of blends did not significantly change from time of seeding in Sept. 1999 to Apr. 2000 or from Apr. 2000 to Oct. 2000. Two of the three blends were significantly different by Oct. 2000 relative to the percentages seeded in Sept. 1999.
In 2003 and 2004, a new herbicide containing three active ingredients was evaluated for efficacy on important weed species and the tolerance of popular ornamental plant species. Currently available ornamental herbicides differ greatly in the weeds they control and tolerance of ornamental plants grown in production nurseries. This new granular product, trade name Showcase, also known by its experimental number, GF-1162, contains 2% trifluralin, 0.25% isoxaben, and 0.25% oxyfluorfen. With preemergent applications applied to pots artificially infested with weed seed, GF-1162 demonstrated exceptional control of many difficult to control species, such as spurge, groundsel, bittercress, oxalis, and crabgrass. When applied preemergence at 150 lb/acre, GF-1162 was as efficacious as current standards. At 200 lb/acre, weed control was exceptional, exceeding all products included in the trials. Ornamental tolerance to GF-1162 was comparable to that of Snapshot TG, with the exception of whorled plants. On whorled plants, such as daylily and hosta, where granular products can be retained on leaf surfaces, products containing oxyfluorfen must be applied with special precautions to immediately shake or wash granules from leaf surfaces. Even when whorled plants were injured by GF-1162, they did eventually recover. GF-1162 received a federal registration in 2004 and state registrations may be complete as early as Spring 2005, at which time this new herbicide would be made available to ornamental nurseries and lawn care companies as an alternative to current herbicide options.