Somatic hybridization has been used for citrus rootstock breeding in many countries. In USA, many reports had proved the efficiency of procedures for the isolation and culture of citrus protoplasts. This research was conducted to evaluate the efficiency of procedures of protoplast isolation using embryogenic callus of the Cleópatra mandarin rootstock. Alterations were proposed to increase protoplast isolation and culture method. Results show the possibility of a protoplast yield of 1.4 to 4.7 x 10(6) pps/g.f.w. for Cleópatra tangerine rootstock callus. Protoplast yield can be raised to 4.7 x 10(6) pps/g.f.w. if the embryogenic callus are grown in a medium supplemented only with 4% sucrose and pre-treated with 1% w/v macerozyme for 1 hour, at 120 rpm, in dark, is applied before protoplast isolation.
Cleópatra mandarin; protoplast; isolation