Growth curves of irrigated temperate forage species
Abstract
The objective was to estimate and compare the seasonal production pattern of 15 grasses and legumes. Four experiments were conducted between 1996 and 1999, each of which consisted of two replicates, with four main plots being distributed at random. In each main plot the grasses or legumes were also distributed at random in subplots. The main plots were cut in staggered sequence in four patterns of harvest. Each cutting date after the initial cutting was selected based on morphological characteristics of the forages. According to specifications of the methodology employed, the daily growth rates and dates of cutting of four successive main plots were used to establish each point on the growth curve. Seasonal daily growth rates were also determined. The extreme values observed for seasonal growth rates in kgDM. ha-1. day-1 were, for perennial grasses: 2.8 and 29.8 in autumn, 0.1 and 19.3 in winter, 24.4 and 67.6 in spring and 9.5 and 44.5 in summer; for perennial legumes: 2.8 and 22.0 in autumn, 5.6 and 42.4 in winter, 3.6 and 97.0 in spring and 2.1 and 75.2 in summer; and for winter cereals: 8.2 and 13.2 in autumn, 7.6 and 14.6 in winter and 26.9 and 34.9 in spring. The best cultivars in each trial were: Medicago sativa cv. Perla sp INTA, Festuca arundinacea cv. El Palenque Plus, Bromus willdenowii cv. Martín Fierro y Triticale cereale cv. Yagán INTA, with daily growth rates for the total period of 54.8, 29.6, 31.3 and 18.1 kgDM. ha-1. day-1, respectively.
