GREEN MANURES OF OAT, RAPE AND SWEET CORN FOR REDUCING COMMON ROOT-ROT IN PEA (PISUM-SATIVUM) CAUSED BY APHANOMYCES-EUTEICHES

Green manure crops of sweet corn, soybean, alfalfa, snap bean, rape, p ea and of the two oat cultivars 'Dane' and 'Troy' were incorporated in to the same soil and containers in which the crop had grown for five w eeks. The soil was then evaluated for suppression of common root rot ( Aphanomyces euteiches) of pea grown in infested pasteurized and non-pa steurized soils in the greenhouse. Pea biomass seduction and a plant b ioassay for A. euteiches were used to measure the green manure suppres sion of disease. Green manures of sweet corn cv. 'Jubilee', oat cv. 'T roy', and rape cv. 'Humus' significantly reduced pea biomass losses ov er the non-amended control soil treatments. Oat cv. 'Troy' and sweet c orn cv. 'Jubilee' green manures significantly reduced inoculum density of A. euteiches over the corresponding fallow controls in inoculated pasteurized soil by 87% and 76%, respectively, and in inoculated non-p asteurized soil by 67% and 66%, respectively. Only the green manure of oat cv. 'Troy' reduced inoculum density significantly below fallow.