Table 2.

Synergistic effect of chitosan and lactic acid bacteria J02 and J13 on the reduction of soft rot severity as assayed on radish slices

Treatmenta	Area of necrotic lesions (mm2)b
	200×		400×
	Chitosan	Mock	Chitosan	Mock
MRS + J02	0 c B	500 ± 40.83 b A	37.75 ± 8.07 cd B	347.5 ± 23.72 bc A
MRS + J13	0 c B	803.25 ± 87.85 a A	0 d B	333 ± 28.67 c A
MRS + LA	0 c B	291 ± 12.72 cd A	139.5 ± 14.34 bc B	504.75 ± 82.67 ab A
MRS	237 ± 11.20 b B	860.5 ± 89.73 a A	217 ± 21.83 b A	236.75 ± 27.60 c A
DW + LA	0 c B	112.75 ± 4.09 d A	156.25 ± 25.24 b B	319.5 ± 48.87 c A
DW	411.5 ± 28.15 a A	333.5 ± 73.73 bc A	485.5 ± 80.17 a A	649.25 ± 92.10 a A

^aLactic acid bacteria were cultured in De Man, Rogosa and Sharpe (MRS) at 37°C for 5 days, diluted, and mixed with 1% chitosan. Both lactic acid bacteria broth and P. carotovorum subsp. carotovorum (Pcc) suspensions (10⁸ colony-forming unit/ml) (35 µl each) were applied onto a filter paper disc overlaid on radish as shown in Fig. 1 and incubated at 30°C for 2 days. Pcc suspensions mixed with distilled water (DW), MRS medium, and DW + or MRS + 2% lactic acid (LA) were used as mock controls.

^bEach treatment contained four replicates. Means followed by the same case letters in each panel were not significantly different according to Fisher’s least significant difference test (P ≤ 0.05). Different lower-case letters indicate a significant difference among various treatments and different capital letters indicate a significant difference between chitosan and mock.