Proliferation-rate effects of BAP and kinetin on banana (Musa spp. AAA group) 'Basrai'

Abstract

The effect of benzylaminopurine (BAP) and kinetin alone and in combination with indole 3-acetic acid (IAA) on shoot proliferation of 'Basrai' (Musa spp., AAA group) was investigated. Shoot tips (4-6 mm) were excised from field-grown suckers to initiate the cultures. Concentrations of BAP and kinetin ranged from 0.0 to 8.0 mg·L-1 each on solid or in liquid MS medium. When liquid medium was used, cultures were agitated continuously on an orbital shaker moving at 40 rpm. Three subculture regimes were employed; after each subculture, the number of shoots regenerated from each explant was counted. The results showed that the multiplication rate was significantly (P ≤ 0.05) dependent upon cytokinin type, its concentration, and type of medium used. The maximum number of shoots regenerated from a single shoot tip was achieved in liquid MS medium containing 4.0 mg·L-1 BAP. There was no significant difference between liquid and solid medium when kinetin was used; however, kinetin at 4.0 mg·L-1 or above yielded significant results as compared with the control and lower kinetin concentrations. The results demonstrated that 4.0 mg·L-1 BAP with 1.0 mg·L-1 IAA in liquid medium was best for shoot multiplication and shoot height during micropropagation of 'Basrai'.