EFFICACY OF BANANA PLANTLET PRODUCTION BY MICROPROPAGATION

The use of banana (Musa spp.) plant production by tissue culture is in creasing throughout the world. However the occurrence of somaclonal va riation has been one of the most important problems affecting the comm ercial value of the plants. A reason for the somaclonal variation can be the time of permanence of the culture in vitro, i.e., the number of subcultures, With the aim of evaluating the effectiveness of banana p lant production from shoot tip in vitro, and the behavior of vegetativ e apices coming from different rhizomes of cv. Nanicao, nine shoot tip s were cultured in MS medium supplemented with 4.5 mg/L BAP for six su bcultures at four-week intervals. The evaluations were done at each su bculture by counting the number of new shoots produced. The results sh ow that shoot tips coming from different rhizomes behave differently u nder in vitro conditions, some being highly productive and others prod ucing a much smaller number of plants under similar culture conditions . The average number of plants produced was 676 per shoot tip after si x subcultures, with 1,850 plants produced by the most productive, agai nst 143 plants produced by the lowest productive one. These data can b e very useful for micropropagation companies in the screening of the m ost promissor shoot tips in the beginning of the culture and in the ec onomic calculations of the individual plantlets prices.