Soil type, management history, and soil amendments influence the development of soil-borne (Rhizoctonia solani, Pythium ultimum) and air-borne (Phytophthora infestans, Hyaloperonospora parasitica) diseases

Abstract

The impact of soil type, long-term soil management, and short-term fertility input strategies on the suppressiveness of soils against soil-borne (Ocimum basilicum -Rhizoctonia solani, Lepidium sativum -Pythium ultimum) as well as air-borne (Lycopersicon esculentum -Phytophthora infestans, Arabidopsis thaliana -Hyaloperonospora parasitica) diseases was studied. Soils from field trials established in five European sites with contrasting pedoclimatic conditions were examined. Sites included (i) a long-term management field trial comparing organic and conventional farming systems (DOKtrial, Therwil, Switzerland) (ii) a short-term fertility input field trial comparing mineral and organic matter fertilisation regimes (Bonn (BON), Germany) (iii) two short-term fertility input field trials (Stockbridge (STC) and Tadcaster (TAD), UK) comparing the impact of farmyard manure, composted farmyard manure, and chicken manure pellet amendements and (iv) soil from a site used as a reference (Reckenholz (REC), Switzerland). Soil type affected disease suppressiveness of the four pathosystems signficantly, indicating that soils can not only affect the development of soil-borne, but also the resistance of plants to air-borne diseases at relevant levels. Suppressiveness to soil-and air-borne diseases was shown to be affected by soil type, but also by long-term management as well as short-term fertility inputs.

Enhancing Soil Quality and Plant Health Through Suppressive Organic Amendments

“…In fact, compost amendments have a consistently demonstrated suppressive effect on several soil-borne diseases, such as damping-off and root rots (Pythium ultimum, Rhizoctonia solani, Rosellinia necatrix, Phytophthora spp.) and wilts (Fusarium oxysporum and Verticillium dahliae) in a wide range of crops [14,36,[38][39][40][41][42][43] ( Table 1). The use of organic amendments or mulches has been successfully incorporated into the integrated management of certain diseases, such as the avocado root rot caused by P. cinnamomi, in combination with genetic host resistance, fungicide applications or physical inactivation [44].…”

Site-specific field resistance of grapevine to Plasmopara viticola correlates to altered gene expression and was not modulated by the application of organic amendments

“…For instance, A. thaliana plants grown on different soil types differed in their susceptibility to downy mildew caused by H. arabidopsidis by a factor of six (i.e. plants grown on the most suppressive soil were six times less infected than plants grown on the least suppressive soil), whereas tomatoes grown on the same soils only differed by a factor of 0.2 (Tamm et al 2010). To our knowledge, no such relevant differences between sites have been reported before for resistance of woody perennial plants such as grapevine to air-borne diseases.…”

“…Several studies have demonstrated that suppressiveness of natural soils to soil-borne, but also to airborne diseases can be affected by the application of organic soil amendments such as manure and compost (Fuchs et al 2004;Litterick et al 2004;Tamm et al 2010;Vallad and Goodman 2004). However, the effect of soil-amendments on resistance of various plant species to soil-and air-borne diseases was much smaller than site-specific effects (Tamm et al 2010). In the present study, we found no evidence that the resistance of grapevine to P. viticola can be influenced by the application of composts.…”

“…Soils in which plants develop no or reduced disease symptoms, even if a pathogen is present or artificially added to the soil, are known as suppressive soils (Weller et al 2002). Certain soils even influence the susceptibility of plants to foliar diseases (Tamm et al 2010). Living soil microorganisms have been identified as a key factor to reduce the occurrence and severity of soil-borne diseases (Knudsen et al 2002;Menzies 1959;Shipton et al 1973;Stutz et al 1986;Wiseman et al 1996), as well as the resistance of plants to foliar diseases (Thuerig et al 2009).…”

“…Several studies have demonstrated that suppressiveness of natural soils to soil-borne diseases can be modulated by the application of organic soil amendments such as manure and compost (Fuchs et al 2004;Litterick et al 2004), and a few reports have shown the same for suppressiveness of soils to airborne diseases (Tamm et al 2010;Vallad and Goodman 2004). Yet, differences between management strategies were much smaller than differences between soil types (Tamm et al 2010), and little is known about the effect of soil management practices on the resistance of woody perennial plants to foliar air-borne diseases.…”