Sementes e miniestaquia em Nectandra megapotamica (Spreng.) Mez. e sementes e micropropação em Handroanthus chrysotrichus (MART. ex DC.) J. Mattos

Abstract

Nectandra megapotamica (Spreng.) Mez. and Handroanthus chrysotrichus (Mart. ex DC.) J. Mattos are Brazilian native species that have great economic importance, ecological, silvicultural and ornamental. However, there is loss of viability of the seeds after collection, and usually the germination decreases sharply after storage. As a result, studies are needed that allow better understand the nature of these species, to obtain good quality seedlings, with conditions to resist adverse conditions, survive and grow at a level compatible with the expected economically. Thus, the general objective of this study was to evaluate methodologies that can contribute to the propagation of N. megapotamica and H. chrysotrichus. In N. megapotamica were evaluated the physical, physiological and sanitary quality of a seed lot, assessing different culture media, and analyzing the ex vitro rooting of shoots of N. megapotamica exposed to different concentrations of IBA, through minicutting. In H. chrysotrichus were conducted in physiological and health quality tests from two different seed lots, stored in a refrigerator at different ages. For multiplication, different antioxidants were tested (Polyvinylpyrrolidone PVP and activated charcoal) in the control of phenolic oxidation in nodal segments. For rooting in vitro micropropagated shoots were subjected to treatments which have been tested in media containing vermiculite in the presence or absence of agar, and the acclimatization of the plants produced. The results indicated that the seeds of N. megapotamica showed variations as biometric aspects, high humidity and association with microorganisms. For rooting, it was possible to promote the rooting of cuttings in solution of 1000 mg L-1 IBA, 60 days in a greenhouse, however this evaluation was not enough and additional studies will be conducted. As for H. chrysotrichus was observed that the seeds differ in their physiological and sanitary quality, and lose their viability after storage in a refrigerator. The antioxidant activated charcoal was more effective on the control of phenolic oxidation in nodal segments of H. chrysotrichus. The medium ½WPM with vermiculite, in the absence of agar favored the in vitro rooting of shoots and seedlings performed well during acclimatization.