Micropropagação de porta-enxertos híbridos de Vitis labrusca x Vitis rotundifolia com resistência à pérola-da-terra (Eurhizococcus brasiliensis Hempel, Hemiptera: Margarodidae)

The homogeneous production of rootstock resistant to perola-da-terra (Eurhizococcus brasiliensis Hempel, Hemiptera: Margarodidae) and well adapted to the growth conditions of the main grape growing region of Southern Brazil by the use of the micropropagation technique, may come to solve the demand of the grape productive sector and avoid losses caused by this pest. The objective of this work was to develop a protocol of micro propagation for the hybrids 1 and 2, which have the desired genetic qualities and vigor to be used as rootstock resistant to perola-da-terra. From axillaries buds cultivated in Galzy culture medium with 3 mu M of BAP, it was possible to induce multiple shooting with a reasonable number of shoots, which may be improved by successive subcultures in the same medium. The shoots were transferred to Galzy culture medium with 8 mu M. 10(-3) of NAA and all of them rooted, overcoming the rooting step that has been pointed out as the main barrier for micro propagation of the species Nits rotundifolia and its hybrids.