[Effects of different irrigation minima on green period and cold-resistance physiological indices of Festuca arundinacea].

A pot experiment was conducted to study the effects of different irrigation minima [80% field capacity (FC), 70% FC, 60% FC and 50% FC] from late autumn to early winter on the green period and cold-resistance of Festuca arundinacea. Under the low temperature in winter, treatments 80% FC and 70% FC made the leaf relative water content, POD, CAT, and SOD activities, and chlorophyll, soluble sugar, and free proline contents of F. arundinacea maintained at a higher level, but made the MDA content and electrolyte leakage decreased, resulting in an increased cold-resistance of F. arundinacea. Treatment 80% FC made the green period of F. arundinacea prolonged by 4, 22 and 28 days, as compared with treatments 70% FC, 60% FC, and 50% FC, respectively, and made F. arundinacea have the shortest time to wither in winter and to turn green in spring, with the longest green period. Taking water-saving and water use efficiency into consideration, 70% FC would be the optimum irrigation low limit from late autumn to early winter for F. arundinacea.