Relation between soil health, wave-like fluctuations in microbial populations,and soil-borne plant disease management

Long-term orchard groundcover management systems affect soil microbial communities and apple replant disease severity

“…Termorshuizen and Lotz (2002) noted that glyphosate applications may increase opportunistic root pathogens on weakened or dying plants. Incorporating dead plant residues can also increase populations of potentially pathogenic soil-borne organisms such as Pythium and Rhizoctonia (van Bruggen et al 2006). …”

Supplementing chemical fertilizer with an organic component increases soil biological function and quality

“…Employing DGGE, Biolog, and FAME analysis methods, a timeseries experiment with and without grass-clover was carried out over a period of nine days by van Bruggen et al (2006) to determine the response of copiotrophic bacterial CFUs to the disturbance of organic matter added into sandy soil. The results showed that copiotrophic CFUs oscillated over time in a wave-like fashion after amendment of the soil, and greater copiotrophic CFUs were always obtained in grass-clove addition treatment than in control.…”

Managing Crop Disease through Cultural Practices

“…It can alter soil texture, aeration, temperature, moisture and density, and can also infl uence nutrient release in the soil with benefi ts to the crop (Ball et al, 2005). Tillage also leads to clear fl uctuations in microbial activity and biomass in the soil (van Bruggen et al, 2006). Reduced tillage or no-tillage is often associated with higher microbial biomass and activity in upper soil layers compared to regular tillage (ploughing) (van Diepeningen et al, 2005).…”

“…van Bruggen et al (2006) argue that healthy soils are more suppressive to soil-borne plant pathogens than biologically impoverished soils. These authors defi ne a healthy soil as a stable soil system with high levels of biological diversity and activity, internal nutrient cycling, and resilience to disturbance.…”

“…These authors defi ne a healthy soil as a stable soil system with high levels of biological diversity and activity, internal nutrient cycling, and resilience to disturbance. The implication is that microbial fl uctuations following a disturbance would dampen more quickly in a healthy than a biologically impoverished soil (van Bruggen et al, 2006). The authors suggest that regular addition of soil organic matter might increase background levels of microbial activity, increase nutrient cycling, lower the concentrations of easily available nutrient sources, increase microbial diversity and enhance natural disease suppression (van Bruggen et al, 2006).…”