Enraizamento de estacas do porta-enxerto de marmeleiro (Cydonia oblonga Mill.) cv. EMC, em diferentes substratos, concentrações de ácido indolbutírico e enxertia de raiz

Abstract

The objective for this study was to evaluate the effects of different substrates, concentrations of indolebutyric acid (IBA), and root grafting on the rooting of quince (Cydonia oblonga Mill.) cv. EMC hardwood cuttings. Two experiments were carried out. In the experiment 1, four concentrations of IBA (0; 1000; 2000 and 3000 mg.L-1) were tested. In the experiment 2, cuttings with or without root grafting were tested. In both experiments the cuttings were placed in one of the three substrates: vermiculite; Plantmax® ; or Plantmax® + vermiculite, 1:1 (v/v). The variables evaluated were: root length; number of shoots per cutting; percentage of rooted cuttings; and percentage of survival of rooted cuttings in the field. In the experiment 1, it was observed: a positive linear relation between IBA concentration and number of roots per cutting. On the other hand, there were negative linear relations between IBA concentration and: number of shoots; shoot length; and rooted cutting survival, respectively. Regarding to number of roots per cutting and percentage of rooted cuttings, both variables presented quadratic relation with IBA concentrations. The thresholds for root length was 1534 mg.L-1 of IBA and rooted cuttings percentage was 2119 mg.L-1 of IBA. In the experiment 2, it was observed that: root grafted cuttings had higher number of roots and lower shoot lengths when used the substrate Plantmax® + vermiculite. In the field, the highest plant survival (93.75%) was observed in those from direct rooting cuttings in the vermiculite substrate.