Phenology of warm-season forage genotypes in rangelands of southwestern Buenos Aires

TORRES, Y.A., C.A. BUSSO, O.A. MONTENEGRO, H.D. GIORGETTI, G.D. RODRÍGUEZ, T. MONTANI Y A. MAIDANA

Tafí del Valle, Tucumán

Jornada; XXIV Jornadas Científicas de la Asociación de Biología de Tucumán; 2007

Asociación de Biología de Tucumán

This study shows a detailed phenological analysis of the most abundant, native, palatable warm-season perennial grass in southwestern Buenos Aires,  Pappophorum subbulbosum, and of 2 palatable perennial grasses, Leymus cinereus cultivars 'Magnar' and 'Trailhead', recently introduced from the U.S.A. Studies were conducted at the field in the Chacra Experimental de Patagones. Half of the plants were defoliated to 5 cm stubble height (apical meristems were not removed). The other half of the plants remained undefoliated (control). Rainfall can be a major factor in determining phonological stages in the study region. Native species appear adapted to synchronize their phenology to rainfall availability. Since it can be extremely variable in the study semiarid region, P. subbulbosum initiates reproductive development early enough as to guarantee their survival in the plant community.