Obtainment of embryogenic cell suspensions from scalps of the banana CIEN-BTA-03 (Musa sp., AAAA) and regeneration of the plants
The purposes of this work were to obtain embryogenic cell suspensions (ECS) from scalps and to regenerate plants of the banana CIEN-BTA-03. Shoot apexes were grown in the scalp-induction medium of Murashige and Skoog plus BA and IAA, following four diverse treatments. The first two, ME22 and ME25, were solid media supplemented with (mg L-1) 22.7 BA plus 0.192 IAA, and 25 BA plus 0.217 IAA, respectively, all containing 1.8 g L-1 of phytagel, and subcultures were performed monthly and bimonthly over 16 months. The other two treatments, IT22 and IT25, resembled ME22 and ME25 but consisted in temporary immersion for four months without subcultures, followed by two months in solid media. The scalps were grown in callus-induction medium and embryogenic calluses were obtained with abundant somatic embryos, especially in scalps from IT25. About 10 to 15 embryos from each were transferred to 5 ml of multiplication medium to initiate the ECS. The scalps obtained from the IT25 treatment were the most successful as they led to ECS with high embryogenic capability. In addition, IT25 decreased the timespan required for the production of scalps. The obtained ECS gave rise to secondary somatic embryos. It showed a high multiplication index, as well as numerous mature somatic embryos, and good conversion of embryos and plant regeneration.