SUPERFICIAL DISINFESTATION OF ISOLATED EXPLANTS FROM SEMI-HARDWOOD AND HERBACEOUS BRANCHES OF Eugenia involucrate DC. (MYRTACEAE)

Abstract

This study aimed to compare two methods of surface disinfestation of explants isolated from semi-hardwood and herbaceous branches of Eugenia involucrata DC. (Myrtaceae) to obtain aseptic cultures. The better control of bacterial contamination in nodal segments from semi-hardwood branches was obtained by immersion for 25 minutes in sodium hypochloride at 1.5%. However, 39.35% of explants showed bacterial colonies and excessive contamination made it impossible the cultures. Apical and nodal shoot segments derived from herbaceous branches did not differ and showed reduced fungal contamination (13.75%) and bacterial contamination (0.41%), and high in vitro establishment (91.92%). Sodium hypochlorite at 1.5% in the time tested is not efficient in promoting surface disinfestation of nodal segments that already present woody aspects. It is possible to obtain aseptic cultures of E. involucrata for growing shoot apical and nodal segments obtained after the pruning, and sterilized with the aid of mercuric chloride and sodium hypochlorite.