Green manure crops of sweet corn, soybean, alfalfa, snap bean, rape, pea and of the two oat cultivars 'Dane' and 'Troy' were incorporated into the same soil and containers in which the crop had grown for five weeks. The soil was then evaluated for suppression of common root rot (Aphanomyces euteiches) of pea grown in infested pasteurized and non-pasteurized soils in the greenhouse. Pea biomass reduction and a plant bioassay for A. euteiches were used to measure the green manure suppression of disease. Green manures of sweet corn cv.'Jubilee', oat cv.'Troy', and rape cv.'Humus' significantly reduced pea biomass losses over the non-amended control soil treatments. Oat cv.'Troy' and sweet corn cv.'Jubilee' green manures significantly reduced inoculum density of A. euteiehes over the corresponding fallow controls in inoculated pasteurized soil by 87% and 76%, respectively, and in inoculated non-pasteurized soil by 67% and 66%, respectively. Only the green manure of oat cv. 'Troy' reduced inoculum density significantly below fallow.
Bibliographical noteFunding Information:
We gratefully acknowledge the funding support provided by the Minnesota Agricultural Experiment Station based on research conducted under Project 22– 92H, the Agricultural Utilization Research Institute, and Cool Season Food 26 Legume CSRS Special Grant UID/061–K552 MN/USDA/Sub. Published as paper No 21,773 of the contribution series of the Minnesota Agricultural Experiment Station.
- Crop residue
- Rolled towel bioassy
- Root rot
- Snap bean