Development of direct regeneration protocol for mass multiplication of Musa spp. variety Udhayam (Pisang Awak, ABB) using different explants

Abstract

Musa spp. variety Udhayam (Pisang Awak, ABB) is the first high yielding selection from ICAR-NRCB, Trichy released during 2005. The demand for quality planting material shows an increasing trend because of its higher yield (40%) than the local Karpuravalli. But this variety is highly recalcitrant for shoot tip culture owing to its high phenolic exudation, and very low shoot proliferation rate (<2.0). Therefore, in the present study, attempts were made to develop direct regeneration protocol for the aforementioned variety using various explants like cormlets and male floral hands other than shoot tips. Results revealed that the direct regeneration protocols using cormlets and male floral hands were totally free from latent contamination and recorded high rate of shoot multiplication as against shoot tip explants. Among the three explants used, immature male floral hands showed not only higher multiplication rate under in vitro conditions and also performed better under field conditions compared to shoot tip and cormlet derived plants. The plantlets derived from different explants were found to be true to type as confirmed using ISSR markers. Field performance of the plants derived from various explants indicated that though all are suitable for direct regeneration, male floral hands was superior followed by sucker, shoot tip and cormlets in terms of bunch yield and crop duration. Key message: Immature male flower buds are the best explants for mass multiplication through direct regeneration and commercial exploitation in banana variety Udhayam (Pisang Awak, ABB).