Tropical Grasslands (2001) Volume 35, 161167
Forage yield and nutritive value of Eragrostis curvula and Digitaria eriantha in central-south semi-arid Argentina
A.O. GARGANO1,2, M.A. ADÚRIZ1, H.M. ARELOVICH1,3, and M.I. AMELA1
1Departamento de Agronomía, Universidad Nacional del Sur, Argentina
A clipping experiment was conducted over 4 consecutive years at Bahía Blanca (Argentina) to evaluate dry matter (DM) yield, crude protein (CP) concentration and in vitro DM digestibility (IVDMD) in Digitaria eriantha cv. Irene and Eragrostis curvula cv. Tanganyika. During spring and summer (mid-October to mid-February) the plants were cut whenever they reached 25–30 cm height. The same measurements were also performed for the autumn regrowth on June 1 and July 15 each year. The 4-year average of total DM yield for the spring-summer and deferred growth periods were 2812 and 798 kg/ha for D. eriantha, and 3591 and 729 kg/ha for E. curvula, respectively. The CP and IVDMD values were: D. eriantha 12.1 and 5.0%; 64.0 and 50.8%; and E. curvula 9.2 and 3.9%; 51.6 and 40.4%, for the spring–summer and deferred periods, respectively. Differences in spring–summer yields between species depended upon the initiation of the growing cycle. Quality of deferred forage was significantly higher for D. eriantha. However, a large proportion of leaf lodging was observed for its deferred forage mass. This problem may substantially reduce the ability of grazing animals to harvest this forage.