A Novel In Vitro Protocol for Inducing Direct Somatic Embryogenesis in Phalaenopsis aphrodite without Taking Explants

Table 1

Number of embryos formed on the distal site of shoots of 2-month-old seedlings, depending on culture systems and concentration of cytokinins.

PGR treatments (mg L^−1)	Solid medium	Two-layer medium	Two-step culture
PGR-free	0^d*	3.6^b	5.0^b
BA
1	5.8^c	4.0^b	7.0^b
2.5	7.4^bc	7.6^ab	10.4^b
5	5.6^c	5.6^b	7.8^b
TDZ
0.1	8.2^bc	6.8^ab	19.0^ab
0.5	15.4^a	15.0^a	16.6^ab
1.0	9.2^b	12.4^ab	28.8^a

∗Data in the same column followed by the same letters are not significantly different by Duncan’ multiple range test at P < 0.05.