Wednesday, November 7, 2007
268-5

Effects of Wear Stress on Basal Rot Anthracnose Severity in Agrostis Species and Genotypes.

Jason Dowgiewicz, University of Massachusetts, Stockbridge Hall, Amherst, MA 01003, Jeffrey Ebdon, 12F Stockbridge Hall, University of Massachusetts, University of Massachusetts, Department of Plant, Soil & Insect Sciences, Amherst, MA 01003, Michelle DaCosta, University of Massachusetts, University of Massachusetts, Dept of Plant, Soil & Insect Sciences, 11 Stockbridge Hall, 80 Campus Center Way, Amherst, MA 01003, and William Dest, University of Connecticut, 53 McMullen Ave., Wethersfield, CT 06109-1234.

Genotype effects on anthracnose disease severity in Agrostis psecies maintained as golf green turf was evaluated near Amherst, MA. The test consisted of 7 velvet (Agrostis canina L.) and 20 creeping bentgrass (Agrostis stolonifera L.) genotypes. Wear treatments were imposed on plots using a grooming brush attached to a walk behind greens mower. Wear treatments were applied uniformly to all plots on 30 October, 2005. Approximately one third of each plot was treated to wear. Cultivars were planted on 3 November, 2003 to 1.5 m x 3 m plots. The experimental design was a randomized complete block with three replications. The green was constructed on a USGA sand base root zone and was maintained at 3.2 mm inch height of cut, fertilized with 172 kg N/ha per season, irrigated to prevent stress, and fungicides were applied preventatively. Plots were rated for anthracnose (1 to 9 scale, 9 = no disease) on 26 April 2006. The identity of the disease was confirmed by the University of Massachusetts Turfgrass Disease Diagnosis Laboratory. Data was analyzed using ANOVA procedures.No basal rot anthracnose was observed in non-wear treated plots, however, significant difference between species and cultivar was detected due to the effects of wear. All entries exhibited acceptable anthracnose resistance except for the experimental entry, ‘SRX 1GD' creeping bentgrass. The experimental entries ‘9200', ‘A03-EDI' and ‘LS-44' creeping bentgrass as well as the commercially available ‘Independence', ‘Penncross' and ‘Pennlinks II' creeping bentgrass exhibited excellent anthracnose resistance (no disease). ‘SR-7200' was the only velvet bentgrass entry providing excellent resistance to basal rot anthracnose. On average, creeping bentgrass entries provided significantly better anthracnose resistance compared to velvet entries, which averaged 8.2 and 7.7 on the 1 to 9 disease rating scale, respectively.