Combined application of soil solarization and organic amendmentin the control of corky root and fusarium wilt in greenhouse tomato

Abstract: Two years greenhouse (2010-2011) experiment was carried out with the aim to studythe efficacy of integration of soil solarization and organic amendment. Organic amendment wasmade using compost (15t ha-1) from organic fraction of urban waste applied after 35 days of soilsolarization. The amendment was applied after soil solarization in order to mitigate the drasticeffects produced by solar heating on microbial community and to reduce mineral fertilization.Disease severity, incidence and yield were evaluated. The experiments were performed in theSouth of Italy at Poggiomarino (Campania region) using the ecotype known as “Pomodoro diSorrento” much appreciated by the market, but that has no resistance to Pyrenochaeta lycopersiciand Fusarium oxysporum f.sp. lycopersici. These two pathogens infect tomato later reducing theharvest season and the grower income. Soil solarization alone had the same efficacy of methamsodium and was effective in reducing diseases giving efficacies of 81.1 and 64.7% (mean of thetwo years) respectively for Fusarium and Pyrenochaeta. The application of organic amendmentincreased efficacy against P. lycopersici (98%) conversely significantly reduced the control ofF. oxysporum (55.3%). Yield was higher in solarized soil than in solarized plus compostamendment due to the higher level of incidence of Fusarium. This approach gave different resultsin relation to the ecological features of the pathogen, in the present work some considerations onthis topic are reported. For fresh tomato under greenhouse, biological and integrated managementis not only applied in order to reduce the ecological impact of the crop, but mainly for technicaland economic reasons. As a matter of fact, the reduced availability of fumigants, the difficultiesto apply fungicides against these two pathogens and the cost of many scheduled fungicideapplications render the integrated and/or the biological disease management the best choice forthis crop.