Crecimiento en longitud foliar y dinámica de población de tallos de cinco asociaciones de gramineas y leguminosa bajo pastoreo

The purpose of the present study was to determine leaf length, net growth, senescence, tiller weight and tiller dynamics of five associations between two grasses and a legume planted in different proportions. Five treatments were evaluated: 4:3:3; 4:6:0; 4:0:6; 4:4:2 and 4:2:4 of white clover, cocksfoot, and perennial ryegrass, respectively. These treatments were distributed in 20 paddocks, 104 m^-2 each, in a randomized complete block design. The greatest increase in both leaf length and leaf net growth in the species tested was found in summer, with 7.1 and 6.53 cm tiller^-1 d^-1 for cocksfoot and 7 and 6.7 cm tiller-1 d-1 for perennial ryegrass; while in white clover no differences in leaf length and leaf net growth and petiole elongation in summer and spring (P>0.05) were not found. The greatest tiller weight in perennial ryegrass and cocksfoot was recorded in summer (0.38 g^-1 stem^-1) and highest tiller population density in the winter season (9,961 and 10,423 tiller m²), respectively. Tissue turnover in the assessed species showed a noticeable seasonality, being more dynamic in summer that in autumn. Associations of three species allowed for one major tiller population dynamics compared to those of two-associated species.