Reproducibility of suppression of Pythium wilt of cucumber by compost

Abstract

There is increasing global interest in using compost to suppress soil-borne fungal and bacterial diseases and nematodes. We studied the reproducibility of compost suppressive capacity (SC) against Pythium wilt of cucumber using nine composts produced by the same composting plant in 2008 and 2009. A bioassay was set up in a greenhouse using cucumber inoculated with two strains of Pythium. The composts were used as 20% mixtures (v:v) of a basic steam-sterilized light Sphagnum peat and sand (3:1, v:v). Shoot height was measured weekly during the 5-week experiment. At harvest, the SC was calculated as the % difference in shoot dry weight (DW) between non-inoculated and inoculated cucumbers. The SC was not affected by year of production (2008 or 2009), indicating reproducibility of SC when the raw materials and the composting method are not changed. Differences in shoot height were not as pronounced as those for shoot DW. The results were encouraging, but further studies are still needed for producing compost with guaranteed suppressiveness properties.

Pseudomonas chlororaphis and organic amendments controlling Pythium infection in tomato

“…Also some other studies demonstrated such a general suppressive effect of compost against Pythium spp. when amended to peat-like growing media (Pane et al 2011;Alfano et al 2011;Vestberg et al 2014).…”