Table 1.

The number of bacteria positive for the clear zone test on emulsified PLA agar plates isolated from soil.

Study	Number of Soils Used	Number of Bacteria Positive for the Clear Zone Test
Tomita et al. 2004 [14]	153	1
Teeraphatpornchai et al. 2003 [21]	400	4
Sukkhum et al. 2009 [20]	80	13
Nakamura et al. 2001 [18]	300	2
Pranamuda et al. 1997 [16]	45	1
Kim and Park 2010 [17]	60	1