The objective of this work was to evaluate the in vitro rhizogenesis response of stem apexes of young plants of 'Tainung 01' papaya tree in different times of permanence in induction and regeneration media. The induction medium was MS, supplemented with organic complements constituted of sucrose, myo-inositol, thiamin, pyridoxine, nicotinic acid and AIB. The regeneration medium differed from the induction medium because it does not have AIB. The treatments consisted of variable times of permanence of the explants in the induction and regeneration media (induction/regeneration): 0/25; 5/20; 10/15; 15/10; 20/5 and 25/0 days. The experimental design was completely randomized, with six treatments and four repetitions, with each experimental unit represented by five test tubes. The maximum rooting and the maximum length of the largest leaf were obtained around 16 days after the branches were incubated in the induction medium. For the variables ‘number of roots’ and ‘larger prolongation of the branches’, the maximum results were obtained after approximately 15 days in the induction medium. Therefore, this work concludes that, for good rooting pattern, the permanence of the branches in medium of induction for a period of 15 to 16 days is essential.
Carica papaya; auxin; micropropagation; tissue culture
