Drought tolerance of Paspalum notatum subjected to defoliation

Abstract

Drought associated with climate change and climate variability is the main factor affecting the productivity and diversity of terrestrial ecosystems. The objective of this study was to evaluate the tolerance to drought and the compensatory growth of two provenances of Paspalum notatum subjected to defoliation and water deficit. The experiment was carried out under greenhouse conditions, located at the Experimental Station for the Study of the Dry Tropics "El Limón", attached to the UNAN Managua. An experiment was carried out with a factorial arrangement of treatments with three repetitions. Individuals from two provenances of P. notatum were subjected to two levels of defoliation and two levels of water regime. The variables evaluated were dry matter production, relative growth rate and water potential. The main results show the P. notatum plants in conditions without water stress in an increase in their aerial biomass by 15%, the accumulation of rhizome biomass of defoliated plants was lower in relation to the non-defoliated plants, the root biomass was dependent on the water regime, the total accumulated biomass increased by 20% in non-defoliated conditions and the defoliated plants of Muy Muy showed overcompensation and the defoliated plants of Rivas presented a partial compensation. The water potential in defoliated plants did not show differentiation, regardless of the water regime to which they were subjected. Drought is a determining factor that modifies the compensatory capacity of grasses subjected to defoliation in aerial biomass and rhizomes.