Identification of the effect of Benzylaminopurine on shoot regeneration of cavendish banana

Abstract

The Cavendish banana (Musa acuminata) is a commercially significant cultivar in the global horticultural market and is extensively propagated using plant tissue culture techniques. In this technique, Plant Growth Regulators (PGRs) are used to enhance rapid propagation for large-scale production. One such PGR, N6-benzylaminopurine (BAP), a synthetic cytokinin, has gained attention for its effects on plant growth and development in tissue culture. The objective of the present study was to evaluate the effects of different BAP concentrations on in vitro shoot multiplication of Cavendish banana. One-month-old in-vitro banana plantlets were used as explants and cultured on Murashige and Skoog (MS) media series, supplemented with a constant 2.0 ppm of Indole-3-acetic acid (IAA) and varying concentrations of BAP (0, 2, 4, 6, 8, and 10 ppm). Cultures were maintained at 26±1oC under a 16-hour photoperiod. After 30 days of culture, shoot number, leaf number, and highest shoot height (cm) were measured. The experiment followed a Completely Randomized Design (CRD) with three replicates per treatment, and each replicate consisted of four explants. Statistical analysis was performed using SPSS software. The results revealed that shoot proliferation and elongation were significantly greater with rising BAP concentrations. BAP concentrations below 2 ppm did not significantly differ from the control in shoot proliferation. The optimum concentration of BAP was found to be 6 ppm for Cavendish plantlets, which produced an average of 1.60 new shoots per explant, 4.50 leaves and a shoot height of 4.40 cm, with a 100% survival rate. Shoot emergence typically began after 12–15 days in 6 ppm BAP medium, while delays were noted in both lower and higher concentrations. Additionally, BAP concentrations above 6 ppm resulted in reduced shoot proliferation and lower plantlet survival rates. It is recommended that future research explore the synergistic effects of BAP with auxins such as IAA or NAA and genotype-specific responses to improve multiplication efficiency and support varietal micropropagation protocols.