Effect of 6-Benzylaminopurine and -Naphthalene Acetic Acid on In vitro Production of MD2 Pineapple Planting Materials

MD2 pineapple is currently the most preferred variety on the international market pleasant aroma and high brix acidity ratio. Large quantities of planting material are needed to replace the existing Smooth Cayene and Sugar Loaf varieties commonly grown by farmers. Therefore in vitro procedures were developed as an alternate method to improve upon the multiplication rate of this variety. Clumped explants were cultured on MS supplemented with 30 g/l sucrose and various combination of 6-benzylaminopurine (BAP) and -naphthalene acetic acid (NAA) in solid or liquid cultures. Liquid cultures required 5.0 mg l BAP to significantly (P<0.05) 1 increase the multiplication rate by 2- or 5-fold compared to 7.5 mg l in solid cultures. When plantlets from 1 optimal treatments were transferred to liquid medium with high concentration (7.5-15 mg l ) of NAA there was 1 no root development. However, the transfer of one or two-month old cultured plantlets to solid MS medium supplemented with NAA or IBA alone or combination of NAA and IBA resulted in root production. The number of root produced per plantlet on a medium supplemented with a combination of NAA and IBA was comparably higher than when NAA or IBA alone were used. The increased multiplication rate of MD2 in vitro will serve as alternate source of planting materials for both subsistence and large-scale farmers in the pineapple industry.