In the present study, we found that a combination of BA
and picloram was optimal for inducing embryogenesis compared
to other plant growth regulators reported. The best
embryogenic response was obtained in MS medium
supplemented with 4.14 μM picloram and 0.22 μM BA, in
which an average of 347 embryos were formed per explant in
100% of the explants which is very high compared to 0–
22.2% in male flower bud explants of various banana cultivars
(Strosse et al. 2006), and 3.6% explants with eight to ten
embryos were formed in a period of 3.5 mo in scalp explants
of Banana CIEN-BTA 03 (Ramírez-Villalobos and de García
2008). Moreover, embryo development occurred within 15 d
compared to the slow development of embryos (8–9 mo) in
the previous reports. This is a substantial advancement in the
protocol for somatic embryogenesis in banana. Induction of
somatic embryos on medium containing picloram has also
been reported in many species (Mendoza and Kaeppler
2002; Preeti and Kothari 2004; Gona and Omid 2008). In
our study, embryos developed not only on the cut surface, but
the entire tissue near the meristem and also on the surfaces of
innermost leaf sheaths (Fig. 1E). Furthermore, these embryos
underwent secondary embryogenesis and the proliferation of
embryos continued for 3 mo in the same media.