Seed treatment with prodigiosin controls damping-off of cucumber caused by Pythium ultimum

AMB Express

Table 2 Suppression of damping-off of cucumber caused by Pythium ultimum in soil-less mix with prodigiosin purified from ethanol extract of Serratia marcescens N4-5

Treatment^a	Mean plant stand per pot at different P. ultimum infestation levels^b
Treatment^a	0	10	30	50
Non-treated seed	4.75 A	4.00 A → D	2.17 E	1.46 EF
Ethanol-only	4.67 AB	3.33 CD	0.79 F	1.13 EF
N4-5 ethanol extract	4.42 AB	4.21 ABC	3.42 CD	3.96 A → D
Purified prodigiosin	4.67 AB	3.71 BCD	3.21 CD	1.58 EF

^aSee “Materials and methods” for a description of treatments. Non-treated, no treatment was applied; ethanol-only, seeds were treated with ethanol only; N4-5 ethanol extract, seeds were treated with ethanol extract of strain N4-5; purified prodigiosin, seeds were treated with purified prodigiosin in ethanol
^bValues were the mean of three experiments (n = 3) expressed as mean plant stand per pot. Results were combined prior to analysis as there was no significant experiment × treatment effect (P = 0.3975). Treatments in all experiments contained eight replicate pots, each containing five seeds. Numbers followed by the same letter were not significantly different (P ≤ 0.05) as determined by a protected least significant difference test. Least significant difference was 0.97. P. ultimum was added at 0, 10, 30, and 50 sporangia/cm³ soil-less mix inoculum