MINICUTTING TECHNIQUE OF YERBA MATE IN FOUR SEASONS OF THE YEAR

ABSTRACT

Ilex paraguariensis is a forest species that has multiple potentialities, being used in the food, pharmaceutical and cosmetic industries. However, the seminal propagation of the species is difficult due to its low (below 20%) and non-uniform germination and the long period (four to six months) stratification of seeds needed for the breaking of embryo dormancy. The minicutting technique is an alternative to overcome such limitations, therefore this study aimed to evaluate the effect of indolebutyric acid (IBA) on rooting of yerba mate minicuttings collected at different seasons (July/2014 to May/2015). Minicuttings were prepared with 6 cm (± 1 cm) long and two leaves reduced by half and, the basal portion of the propagules was immersed for 10 second in different hydroalcoholic solutions of IBA (0,200,400,6000 and 8000 mg L^-1). After 90 days of installation of the experiments, we evaluated the percentage of rooting, root number and average length of three major roots, percentage of callogenesis, leaf retention, developed shoots and mortality. The spring was the most promising season, providing approximately 70% of rooting and coupled the application of 8000 mg L^-1 of the IBA the minicuttings reached the greatest length (4.3 cm) and root number (9.1) as well as the lower callus induction rate (0%). The minicutting collection in the spring and 8000 mg L^-1 of the IBA is the most indicated for minicutting technique of yerba mate.

Keywords:
cloning; Ilex paraguariensis; plant growth regulator; indolebutyric acid