Indolebutyric acid and substrates on Spondias tuberosa layering

Abstract

Spondias tuberosa is a native species from the Brazilian Northeast and northern Minas Gerais State, whose fruits present good market acceptance. However, its large scale propagation is affected by slow and uneven seeds germination, demanding the use of vegetative propagation techniques. This study aimed at evaluating the effect of indolebutyric acid (IBA) application and different kinds of substrate on the vegetative propagation of Spondias tuberosa by layering. The experiment consisted of eleven Spondias tuberosa arrays and a randomized blocks design with four replications, in a 3x5 factorial scheme, in order to evaluate the effect of five IBA doses (0 mg L^-1; 1,000 mg L^-1; 2,000 mg L^-1; 4,000 mg L^-1; and 6,000 mg L^-1) and three substrates (Bioplant^®, vermiculite and sugarcane bagasse). The selected branches were ringed and, subsequently, the concentrated IBA solutions were applied. At 180 days, the percentage of rooted and callous layers, percentage of layers with primordium roots, number of roots per layer, length of the longest root and root fresh and dry weight were evaluated. The use of 6,000 mg L^-1 of IBA promoted a higher growth and development of radicular layers. The use of sugarcane bagasse is recommended, for being easy to get, in the study area, besides presenting adequate chemical and physical features.