Seasonal Changes in Carbohydrate and Protein Content of Seeded Bermudagrasses and Their Effect on Spring Green-Up

The widespread use of warm-season turfgrasses in transition zones of Europe, such as northern Italy, has been hampered by the long dormancy periods. To encourage the conversion from cool- to warm-season grasses, research is needed to identify cultivars that exhibit early spring green-up. A 2-year study was conducted at the agricultural experimental farm of Padova University from November 2006 to October 2008 to compare water-soluble carbohydrate and protein content in stolons of four bermudagrass [Cynodon dactylon (L.) Pers.] cultivars and determine their effect on spring green-up. Samples of ‘La Paloma’, ‘NuMex Sahara’, ‘Princess 77’ and ‘Yukon’ were collected monthly, and water-soluble carbohydrates (WSC) and crude protein (CP) content of stolons were measured. Dry weight values of WSC and CP for each cultivar were regressed against days needed to reach 80 % green cover in spring (D80). ‘Yukon’ exhibited the highest rhizome dry weight and WSC content during the winter months and was the fastest to reach 80 % green cover. Conversely, ‘Princess 77’ was the slowest cultivar to green-up in both years. Regression analysis revealed a stronger relationship between D80 and WSC than between CP content and D80.