IN VITRO MICROPROPAGATION OF BANANA

Abstract

The present study was conducted at the Biotechnology Laboratory, Biotechnology Division, Bangladesh Agricultural Research Institute (BARI), Gazipur during the period from September, 2004 to June, 2005 to investigate the effect of different concentrations of BAP and NAA on virus free plant regeneration, shoot multiplication and different concentrations of IBA and IAA on in vitro root formation ofbanana cv. BARI-I. The culture meristem first turned brown in colour in 4-5 days and after 30-50 days later a green globular hard coat mass grow to be round in shape producing a ball like structure. From this ball like structure adventitious plantlets were developing. Among the different concentration 7.5 mgl," BAP + 0.5 mgl," NAA showed the highest shoot proliferation 0.75, 2.75 and 6.25 shoots per explant at 10, 20 and 30 DAI respectively. The longest shoot was produced by the treatment concentration 7.5 mgl," BAP + 0.5 mgl," NAA treatment (1.03, 2.45 and 3.38 cm) at 10, 20 and 30 DAI respectively. The maximum number of leaves (2.50, 3.25 and 7.00 leaves/explant at 10, 20 and 30 DAI) produced on the medium supplemented with 7.5 mgl," BAP and 0.50 mgl," NAA. The longest leaves was produced by the treatment concentration 7.5 mgl," BAP + 0.5 mgl," NAA treatment (0.85, 2. 70 and 4.23 cm at 10, 20 and 30 DAI) respectively. For root initiation half strength MS medium supplemented with different levels of IBA (0, 0.5, 1.0 and 1.50 rngl.") and IAA (0, 0.5 and 1.0 mgL"1) in order to allow root formation. Root numbers varied with different concentrations of IBA and IAA. The highest number of roots were produced by 0.5 mgl." IAA + 0.5 mgl," IBA (3.50, 4.50 and 6.50 per explant respectively). The highest length was observed at 10, 20 and 30 DAI in the treatment concentration 0.5 mgl," IAA and IBA (2.93, 4.63 and 5.88 cm) which was statistically significant. Meristem derived plantlet transferred to polybags containing 1 : 1 (ground soil : cowdung) mixture after 7 days hardening in room temperature (28-30°C) and established plantlet is ready for planting.