PLANT MORPHOLOGY AND FORAGE NUTRITIVE-VALUE OF 3 BAHIAGRASSES AS AFFECTED BY HARVEST FREQUENCY

Differences in morphological development have been reported among bahi agrass (Paspalum notatum Flugge) cultivars, Relationships of harvest m anagement to these developmental differences and subsequent forage pro duction and nutritive value have not been characterized, A 2-yr study was initiated by harvesting 'Argentine', 'Pensacola', and Tifton 9' ba hiagrass every 20, 30, or 40 d from mid-May until mid-September. Objec tives were to determine if differences exist among these cultivars for leafiness, morphological development, forage mass, and forage nutriti ve value, and to determine if differences were affected by harvest fre quency and season of growth. Leaf percentage by weight, inflorescence development, forage nutritive value, and forage mass were evaluated fo r monocultures of the three cultivars. Argentine had a greater (P = 0. 01) percent leaf (87.2%) than did Pensacola (80.4%) or Tifton 9 (81.0% ). In addition, Argentine and Tifton 9 produced fewer (P = 0.01) inflo rescences at 20- and 30-d harvest frequencies than did Pensacola. Leaf percentage was greater (P = 0.01) at 20- (88.7%) than at 30- (78.6%) and 40-d (81.4%) harvest frequencies. There were cultivar x plant part interactions (P < 0.05) for neutral detergent fiber (NDF) and lignin, but differences were detected only in the stem component, No differen ces (P less than or equal to 0.05) were detected among cultivars for o ther nutritive value variables, Total forage mass was similar (P less than or equal to 0.05) among cultivars. Differences in forage mass wer e detected (P = 0.01) only at the first harvest, where Argentine produ ced less forage (1.9 Mg ha(-1)) than Pensacola (3.1 Mg ha(-1)) or Tift on 9 (2.9 Mg ha(-1)), The combination of greater leaf percentage and f ewer inflorescences indicate that Argentine could have potential advan tages as a forage over other bahiagrass cultivars.