Biocontrol of Penicillium digitatum on Postharvest Citrus Fruits by Pseudomonas fluorescens

Table 2

The effect of P. fluorescens on spore germination and germ tube elongation of P. digitatum.

Treatments	Spore germination (%)	Germ tube length (μm)
Control	87.32 ± 1.14a	49.56 ± 7.29a
Culture filtrate	30.03 ± 0.28b	29.90 ± 3.76c
Autoclaved cultures	29.67 ± 0.69b	39.42 ± 3.56b
1 × 10^6 CFU/mL bacterial suspension	19.80 ± 0.59c	13.27 ± 3.85d
1 × 10^7 CFU/mL bacterial suspension	5.66 ± 0.43d	7.86 ± 1.60e
Bacterial fluid (1 × 10^8 CFU/mL)	1.00 ± 0.82e	4.17 ± 1.18e
1 × 10^8 CFU/mL bacterial suspension	0.66 ± 0.47e	3.75 ± 1.25e

Autoclaved cultures were prepared by autoclaving 1 × 10⁸ CFU/ml bacterial fluid at 121°C for 20 min. Culture filtrate was prepared by using a 0.22 μm polycarbonate membrane filter to filtrate the supernatants. Bacterial suspension was prepared by using SDW to wash the bacterial precipitation twice to remove the residual culture medium and adjusted to designed one with the addition of sterile distilled water. Bacterial fluid (1 × 10⁸ CFU/mL) was prepared by diluting the culture (about 1.5 × 10¹⁰ CFU/mL) with culture filtrates. Values in a column followed by a different letter are significantly different according to Duncan’s multiple range test at level.