IMPROVEMENT OF SOIL SOLARIZATION WITH VOLATILE COMPOUNDS GENERATED FROM ORGANIC AMENDMENTS

Combining organic amendments with soil solarization is a nonchemical a pproach to improvement of the control of soilborne plant diseases. Pat hogen control in solarized amended soil is attributed to a combination of thermal killing and enhanced generation of biotoxic volatile compo unds. Apparently, pathogen sensitivity to biotoxic volatile compounds is enhanced with an increase of soil temperature and acts in combinati on with antagonistic microbial activity, Enhanced biocontrol also may be involved with some amendments. Toxic volatile compounds including a lcohols, aldehydes, sulfides, isothiocyanates, and others were detecte d in soil amended with cruciferous residues during heating. Field sola rization of soil amended with composted chicken manure gave better con trol of pathogens and higher yield of lettuce and tomato than either t reatment alone.