Crude protein (CP, %), yield of protein dry matter (YPDM, kg ha-1), nitrogen use efficiency (NUE, kg dry matter kg-1 N) and nitrogen recovery (NR, %) were evaluated in Digitaria eriantha after exposing this species to various field-treatments during 1998-1999 and 1999-2000 in Bahía Blanca (38 degrees 48′S, 62 degrees 13′W), Argentina. Treatments included (1) 3 N fertilization rates (0, 50 or 100 kg ha-1), (2) 2 row spacings (30 or 50 cm), and (3) 2 methods of fertilizer application (either split at the beginning of spring and summer or applied at once in early spring). Plants were cut leaving 5 cm stubble whenever they reached 26-28 cm. Studied parameters were determined on forage harvested in spring, summer or total annual. Crude protein increased (P < 0.05) as N fertilization increased in both seasons. Total annual CP averaged 9.7, 12.0 and 14.0%, respectively for the 0, 50 and 100 kg ha-1 fertilization rates, respectively. Crude protein was greater (P < 0.05) on forage which received split rather than bulk N fertilization, and mean values were 13.2 and 11.7%, respectively. Forage sown at different row spacings had a similar (P > 0.05) CP concentration. In general, YPDM responded positively (P < 0.05) to N fertilization and to a split application of N fertilizer. Although differences were not always significant, there was an inverse relationship between N fertilization rate and NUE and NR. Nitrogen use efficiency was 34.5 and 24.8 kg dry matter kg-1 N (P < 0.05), and NR was 98 and 79% (P < 0.05) when N fertilization rates were 50 and 100 kg ha-1, respectively. There was a positive (P < 0.05) relationship between rainfall and NUE or NR. Nitrogen fertilization in D. eriantha should be split with a N fertilization rate close to 50 kg ha-1, and using 30 rather than 50 cm row spacing. The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact lbry-journals@email.arizona.edu for further information. Migrated from OJS platform August 2020
Scholarly peer-reviewed articles published by the Society for Range Management. Access articles on a rolling-window basis from vol. 1, 1948 up to 5 years from the current year. Formerly Journal of Range Management (JRM). More recent content is available by subscription from SRM.