Substrate and irrigation scheme on the growth of Parapiptadenia rigida (angico-vermelho) seedlings

Abstract

ABSTRACT: Parapiptadenia rigida (angico-vermelho) is a native arboreal species widely found in central and southern Brazil and is indicated for restoration of degraded areas due to its high plasticity to light gradients and ease adaptation to degraded environments. However, there is still a lack of information on this species regarding the production of quality seedlings, as well as the rational use of the resources involved. Thus, the objective of this study was to evaluate the effects of different substrates and irrigation schemes in the development of P. rigida seedlings. The experimental design used was randomized blocks, in a factorial scheme with split plots, with four substrate formulations (100% peat; 80% peat + 20% carbonized rice husk (CRH); 60% peat + 40% CRH; 40% peat + 60% CRH) and six irrigation schemes (4; 8; 12; 16; 20 and 24mm.day-1). At 180 days after emergence, the following parameters were evaluated: height, stem diameter, height and stem diameter ratio, shoot dry weight, root dry weight, total dry weight and Dickson Quality Index. Use of substrate composed of 80% peat + 20% carbonized rice husk and/or 100% peat, combined with irrigation scheme of 4mm day-1, resulted in the best growth of P. rigida seedlings.