Abstract:The leaves of Phalaenopsis amabilis were used as explants, cultured 1/2MS medium supplemented with 0.1 mg L-1 α-naphthyl acetic acid (NAA), 1.0 mg L-1 thidiazuron (TDZ), 10% coconut milk (CM)(v/v) to induce PLB (protocorm-like body), the effects of cutting and explant size on PLB induction were studied. The results showed that the leaves were cut transversely or longitudinally twice, both induction rate and average PLB number per leaf increased significantly, and the time of PLB formation decreased significantly. The effect of cutting transversely was better than that of cutting longitudinally. When the leaves were divided transversely into three, six and twelve segments, respectively, the PLB induction rates increased significantly and the time of PLB formation decreased significantly compared to the control. The PLB induction rate of six-divided segments was significantly higher than that of the three- and twelve-divided segments. These results showed that cutting and explant size could affect PLB induction from leaves of P. anabilis significantly.
