The in vitro propagation of the banana is accomplished to produce large quantities of seedlings free from diseases. Micropropagation process can be optimized changing the method, but also considering plantlet quality. The objective of this work was to evaluate the influence of the flask size and of the growth medium consistence on the multiplication rate and on the initial plantlet development of in vitro propagated 'Maçã' banana tree. Starting from stem apexes, four subcultures were accomplished (S2, S3, S4 and S5) in MS medium modified with the half of the concentration of the macronutrients, added of 30g L-1 of sucrose, 2.5mg L-1 of BAP (6-benzylaminopurine) in factorial design 2x2: two types of growth media (semi solid by addition of 1.6g L-1 Phytagel™ and stationary liquid), and two flask sizes (250 and 500mL). Plantlets were induced in vitro rooting and acclimatization in greenhouse using trays with 72 cells and later grown in 17x18cm polypropylene bags. Cultivation in liquid medium bottle of 500mL can be successfully adopted for propagation of 'Maçã' banana plantlets because it had larger multiplication rate (25.27), better adaptation in the initial stage of acclimatization and similar performance to the other treatments after 60 days of cultivation in the bags.
micropropagation; Musa spp.; tissue culture; liquid medium
