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Verticillium dahliae Kleb. is a soilborne fungal pathogen of many crops. In potato, it is the major causal agent of Early Dying. In Manitoba, potato fields planted with cv. Russet Burbank are infested with highly pathogenic V. dahliae isolates, which can produce up to 90 % disease severity. The objective of the study was to evaluate selected compost, green manure, and seed-meal treatments, in comparison with the soil fumigant Vapam, for their ability to reduce propagule density of V. dahliae in soil and decrease disease, and to enhance potato yield. Select green manure crops (oriental and white mustard, Canada milk vetch, sorghum-sudangrass, rye, alfalfa, oat/pea mixture), organic amendments (composted cattle manure and mustard seed-meal), and Vapam, and crop sequences that contribute to the suppression of Verticillium, or the improvement of

Approaches to restore productivity to eroded soils are urgently needed to sustain food security. We evaluated plant response to soil-landscape rehabilitation, in which approximately 15 cm of topsoil was moved from depositional landscape positions to the eroded upper slope. Crop response was monitored for 6 yr of a corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] rotation at a severely eroded site and for 4 yr of a wheat (Triticum aestivum L.)-soybean rotation at a moderately eroded site. Experiments were conducted in years with relatively wet springs and droughty summers. In the severely eroded landscape, addition of 15 cm of soil increased crop biomass by 25-95% on a kg ha -1 basis and increased grain yields by 20-49% (corn) and 12-59% (soybean), with the largest yield increases recorded in the most eroded landscape positions. Soil addition increased corn grain protein and test weight. No significant differences were observed in crop emergence rate or stand establishment. In the moderately eroded landscape, soil addition significantly increased crop biomass, but not grain yield. In both landscapes, yields were lower in areas of soil removal than in adjacent areas from which no soil was removed, which is likely at least partially an artifact of the plot design. While more research is needed to evaluate long-term impacts, the results of these studies show that soil-landscape rehabilitation may help alleviate the effects of past erosion and provide immediate benefits to the productivity of severely eroded soils.This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

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