Abstract
The mamalade shrub [Streptosolen jamesonii (Benth.) Miers] is an ornamental species with great potential of use in gardens. These plants have an intense contrast of colors among the flowers and leaves, being the blooming in all seasons during the year. The propagation of this species is mainly by using stem cuttings, besides the vegetative propagation of mamalade is still poorly known. Thus, knowledge about auxins and substrates for rooting may be important for the cultivation and increase the popularization use of these plants for garden purposes. Therefore, this study aimed to evaluate the effect of indolbutiric acid (IBA) and substrates on stem rooting and quality of marmalade bush plants shoot production. The experimental design was completely randomized, in a 5x3 factorial scheme, with 8 replications and one stem per plot. The A Factor consisted of 4 concentrations of IBA 500; 1000; 2000 and 3000 mg L-1 and control (only distilled water). The B factor consisted of the substrates: vermiculite, sand and one commercial -Plantmax®. The herbaceous cuttings were standardized by length, measuring 10 cm with 6 leaves. The treatment was performed submerging the base of the cutting, 3 cm, in an IBA solution for 1 min and then planted in the tested substrates. After 30 days, there were evaluated the percentage of rooting and surviving of the cuttings, number of roots and shoots, length of roots and shoots; length of roots and shoots, and fresh weight of roots and shoots. The IBA concentrations or the substrates do not affect the rooting or survival of the cuttings, however, better quality plantlets are obtained in cuttings treated with 750 to 1456 mg L-1 IBA using the commercial substrate Plantmax®, showing the highest number of roots and the better root and shoots development.
Keywords:
asexual propagation; auxin; floriculture; landscaping; ornamental bush
