Interaction of Sustainable Soil Management Practices and Soil Fumigation on Soil Quality Measures in Plasticulture Strawberry Systems in the SE.

The long-term use of annual soil fumigation in Southeastern (SE) strawberry production, combined with a lack of crop rotation and low organic matter inputs presents a risk for serious declines to soil health in these production systems. The incorporation of sustainable soil management practices into these systems could help counteract these declines while positively contributing to yields. In our two year field study we evaluated the impacts of incorporating sustainable soil management practices into both conventionally fumigated and non-fumigated plasticulture strawberry production systems on indicators of soil helath. The sustainable soil management practices we evaluated were: compost, a summer cover crop mix (Cowpea var. ‘Iron Clay’(Vigna unguiculata) and Pearl Millet (Pennisetum glaucumgenus)), and the beneficial soil inoculants of vermicompost and arbuscular mycorrhizal fungi (AMF). These practices were applied both individually and in several combinations in both fumigation strategies. Biological, chemical and physical soil indicators that when combined make-up soil health were assessed over time, including changes to: microbial community composition, various aspects of soil fertility and soil aggregate size distributions. Results from our study indicate that there are both strong singular effects and some significant interactions between fumigation and sustainable soil management practices on several measures of soil health. Of note was the strong effect (p < 0.001) of fumigation on virtually eliminating populations of AMF throughout the growing season in both years. This is despite the fact that AMF were re-introduced into the fumigated system via the inoculated plug treatment.   These results point to the potential use of certain soil management practices on increasing certain aspects of soil health, but recognize that the detrimental biological effect of fumigation cannot likely be overcome with the implementation of the studied sustainable soil management practices.