Influence of cultivar and cultural practices on chemical composition of tall fescue turf.

摘要

A field trial was carried out from 1999 to 2001 in Legnaro, north-eastern Italy to evaluate the effects of cultivar and cultural practices (fertilizer and mowing management) on some chemical characteristics of live tissues of tall fescue (Festuca arundinacea) turf. Four treatments were compared: (1) 'Safari' mowed at 30 mm when the turf reached the height of 40 mm and treated with N at 200 kg ha-1 year-1 applied in equal parts in February, April, May and September; (2) 'Safari' mowed at 60 mm when the turf reached the height of 80 mm and treated with N fertilizer as in treatment 1; (3) 'Safari' mowed as in treatment 2 and N at 100 kg ha-1 year-1 applied in two equal parts in February and May; and (4) 'Noria' mowed and treated with N fertilizer as in treatment 3. At each season, samples of verdure were taken after the cut and divided into live and dead parts to determine the dry weight of both components. Observations were recorded for crude protein (CP), crude fibre (CF), neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent lignin (ADL), ether extract (EE) and ash content in live tissues. The dry matter of vegetative tissues decreased during the winter, while that of dead tissues increased from May to October and subsequently decreased from October to March. Important changes were observed in the chemical components as a consequence of different management conditions. The reduction of mowing height decreased structural carbohydrates and increased CP and EE. The difference between the two cultivars compared depended on CP (which was higher in 'Safari') and CF (which was higher in 'Noria').