Efeito dos substratos rejeito de vermiculita, fibra e pó de coco verde no enraizamento de alporques de faveleira (Cnidoscolus quercifolius Pohl).

Abstract

The use of alternative substrates for the production of seedlings, besides contributing to the solution of environmental problems caused by the deposition of tons of waste piled up in the streets, in the dumps and mining courtyards, can also reduce the costs of production, resulting in this way, in a more economical and environmentally-friendly alternative. This work aimed to evaluate coconut husk and vermiculite tailings substrates on vegetative propagation of Cnidoscolus quercifolius Pohl, by the technique of air-layering. The experiment was conducted in the period of May to October 2012, in the city of Patos-PB in the experimental area of Research for the Semi-Arid (NUPEÁRIDO). The air layers were made of healthy and vigorous branches of faveleira mother-threes. We used a randomized block design in a factorial 2 x 6 (6 substrates and 2 portions of IBA) with 08 repetitions, totaling 96 plots. After 90 days, layers were evaluated for the presence of air layering with callus and primordium roots percentage of rooted air layers. As for the rooted air layers, the following variables were analyzed: the number of roots, root length (cm), main root length (cm), fresh weight (g) and dry weight of roots (g). The use of IBA at a concentration of 6.0 g L-1 was effective in increasing the length, number, fresh weight and dry weight of Cnidoscolus quercifolius Pohl roots. It was possible to observe the emergence of roots in the air layers surface 21 days after the completion of the layering. The coconut shell powder (T4) and vermiculite tailings (T6) substrates, both associated with the use of IBA induction of rooting at a concentration of 6.0 g L-1 in alcoholic solution, promoted better rooting percentage. In all variables, the highest means were observed with the use of vermiculite tailings and a combination of 1/3 of bark fiber of green coconut + 1/3 of bark powder of green coconut + 1/3 of vermiculite tailing.