Natural bioactivators in physiological performance of beet seeds

Abstract

Sugar beet crop suffers from uneven emergence in field which encourages the search for alternative methods to improve germination performance and the initial development of sugar beet seedlings. The objective of this work was to evaluate the effect of aqueous extract of purple nutsedge (Cyperus rotundus L.) and indole-3-butyric acid (IBA) on the germination and early stages of development of sugar beet seedlings. Two experiments were conducted in a completely randomized design with four replications. The germination test was performed with four replications of 25 seeds per treatment and four replications of 20 seeds were used for the primary root length test. In the first experiment, sugar beet seeds were treated with concentrations of 0,0, 0,5, 1,0, 1,5 mgL-1 of IBA. In the second experiment, the seeds were treated with concentrations of 0, 15, 25, 50 and 100% of the aqueous extract of purple nutsedge and with the best concentration obtained from the synthetic auxin selected in the first experiment. The following tests were performed: germination, first count of germination, germination speed index and root length. The data were analyzed using analysis of variance and the averages were compared by Tukey test at 5% probability and polynomial regression was also made. There was no significant difference between the IBA concentrations compared to the control. The use of aqueous extract of purple nutsedge in the concentration of 100% during soaking sugar beet seeds favor the early development of seedlings and increasing the speed of germination stimulating root protrusion and higher main root development when compared to the use of synthetic auxin and to seeds without any treatment.