EVALUATION OF DIFFERENT CONCENTRATION OF AUXINS IN ROOTING OF Jatropha curcas L. CUTTINGS

Abstract

The influence of three auxins with different concentrations in the rooting of Jatropha curcas L. pine nut cuttings was evaluated. Cuttings were collected with a length of 30±3 cm and a diameter of 20±3 mm. After the cut, they were placed in containers with the cut facing down, and they remained there for three days. Before planting, they were immersed in auxins for 1 h and planted in polyethylene bags of 5 kg capacity, and later 66 ml of each treatment were applied to each pot. The substrate was a mixture of soil and sand. There were 13 resulting treatments with four concentrations (10, 250, 500 and 1000 mg kg^-1) of indole-acetic acid (IAA), indole-butyric acid (IBA), naphthalene-acetic acid (NAA) and a control, distributed in a completely random design with eight repetitions. The number of roots, dry weight of radical and aerial biomass was recorded, and analyzed statistically considering differences between treatments (Tukey 5 %). The results indicated that auxins promoted the root and plant development of J. curcas in a differential manner, depending on the concentration applied. The NAA promoted the highest response, while IBA showed an intermediate response, and IAA was the lowest. The greatest aerial and radical biomass was quantified with the application of naphthalene-acetic acid (NAA), and in terms of greater increase in structures and biomass, it was seen with indole-butyric acid (IBA) and indoleacetic acid (IAA) with the lowest dose applied, respectively.