Table I.

Percentages of TEs differentiated without intervening cell division

PSK-α Concentration	TEs
	% of living cells	% of total TEs
1.0 μm	39  ± 7	81  ± 7
0.1 μm	39  ± 2	87  ± 2
0.01 μm	35  ± 2	82  ± 4
1.0 nm	16  ± 5	86  ± 3
0.1 nm	8  ± 4	NDa
None	1  ± 2	ND

Zinnia mesophyll cells were cultured at an initial density of 2.5 × 10⁴ cells mL⁻¹ in media containing PSK-α at various concentrations. The TE differentiation frequency was determined after 5 d of culture. Data are mean values of three replicates ± sd.

^aND, Not determined.