Effects of 6-benzyladenine and Longitudinal Explant Halving on <I>In Vitro</I> Plantlets Proliferation of 'Namwa Pak Chong 50' Banana

Abstract

The effects of plant growth regulator 6-benzyladenine (BA) and longitudinal explant halving on in vitro plantlets proliferation in ‘Namwa Pak Chong 50’ banana was studied. The experimental design was factorial in CRD with 12 replications, each of one plantlet per replication. The in vitro shoots of banana were cut to 1 cm length, leaves were discarded and stem part were cultured on Murashige and Skoog (MS) medium supplemented with 0, 1, 3, and 5 mg/L of BA. Two explant preparations (whole stem and longitudinally halved stem) were tested for 8 weeks with one subculture at the 4^th week. The results revealed that different BA concentration yielded significantly different in shoot proliferation. BA at 3 mg/L yielded 3.50±0.64 shoots which was not statistically different from 5 and 1 mg/L BA which yielded 2.64±0.75 and 2.64±0.61 shoots, respectively. These shoot numbers were higher than those without BA. For explant preparation, the statistical analysis showed significantly difference that the longitudinally halved stem yielded 3.93±0.67 shoots, while the whole stem yielded 1.10±0.08 shoots. There was also interaction of BA and explant preparation on shoot proliferation. Halved stem cultured on MS medium containing 1, 3 and 5 mg/L BA produced higher number of shoots than other protocols.