DEVELOPMENT OF A RAPID METHOD FOR MICROPROPAGATION OF A NEW PINEAPPLE [ANANAS COMOSUS (L.) MURR.] CLONE, 'YEPPOON GOLD'

‘Yeppoon Gold’ is a locally selected clone of ‘Smooth Cayenne’. It can produce marketable fruit during winter, and its fruits are sweeter and less fibrous than those of other cultivars. Because of these features, it is anticipated that the demand for its propagating material will increase over the next five years. Tissue culture experiments were therefore conducted to develop rapid multiplication procedures for ‘Yeppoon Gold’. Axillary buds from suckers were treated with 0.025% (w/v) mercuric chloride for five minutes and placed in different media. Rapid shoot initiation was found in MS medium supplemented with 1 mg L^-1 BAP after four weeks incubation. Shoots were subcultured by bisectecting vertically and placing on MS or B₅ medium containing 30.0 g L^-1 sugar, 8.0 g L^-1 agar and 0.0, 0.5, 1.0, 1.5, 2.0 or 2.5 mg L^-1 BAP. The highest multiplication was obtained in B₅ medium at 2 mg L^-1 BAP. Repeated subculturing in the same medium for seven months resulted in root initiation. Thus, B₅ medium with 2 mg L^-1 BAP can serve as both multiplication and rooting medium. This protocol, which eliminates the extra step required for root initiation, has the potential to produce up to a million plants per year from about 10-20 suckers.