Morphogenetic characteristics of forage peanut pastures (Arachis Pintoi Krapovickas & Gregory cv. Belmonte) subjected to intensities of continuous stocking management

Abstract

Forage legumes are used with two main purposes in grassland áreas: nitrogen fixation and production of high quality herbage. Such characteristics are basic features of productive and sustainable pastoral systems of animal production, since they reduce the need of nitrogen fertilizers. In that context, the forage peanut has been presented as a promising alternative, because it has a high competitive ability relative to tropical forage grass species due to its growth habit and perennation strategy. However, knowledge regarding its behavior and responses under grazing is scarce, limiting the possibilities of adequate planning of its use in pastoral systems of animal production. The objective of this experiment is to characterize the morphogenetic responses of the forage peanut (Arachis pintoi Krapovickas & Gregori cv. Belmonte) subjected to intensities of continuous stocking management as a means of describing its strategies of growth and development and how they interfere with sward productivity and persistency. The experiment will be carried out at ESALQ/USP, Piracicaba, SP, from November 2012 to April 2014. Treatments correspond to a range of grazing intensities characterized by four sward surface heights (5, 10, 15 and 20 cm) to be maintained constant through continuous stocking and variable stocking rate. These will be allocated to experimental units (210 m2 paddocks) according to a randomized complete block design, with four replications. The following response variables will be studied: leaf appearance, elongation and senescence rate, stolon and petiole elongation rate, leaf lifespan, number of live leaves per stolon, population density of growing and root formation points. The chosen range of grazing intensities (5, 10, 15 and 20 cm) should allow for an adequate contrast between treatments (severe, moderate, lenient and very lenient, respectively), allowing that functional responses of plants to grazing intensity may be studied and important information for inferences regarding the grazing management of this forage plant determined.