Microbial enrichment of compost with biological control agents to enhance suppressiveness to four soil-borne diseases in greenhouse

Abstract

The aim of the present work was to study if the level and reproducibility of suppressive properties of compost can be increased upon enrichment with biological control agents. A compost made from green waste, organic urban waste and urban sludge was inoculated with commercial formulations of Trichoderma and non-pathogenic Fusarium. The compost showed to be suppressive against some soil-borne pathogens, except R. solani, while such activity was lost after sterilisation. The suppressive effect of enriched compost was assessed in greenhouse trials on cucumber, tomato, bean and basil. The addition of T. harzianum T-22 at 4 g l -1 dosage was able to increase suppressiveness against R. solani of a 40% compost and 60% peat mix and to increase biomass of bean compared to a peat inoculated control. The same enrichment did not reduce suppressiveness of compost against P. ultimum and P. nicotianae, so its addition might be considered a good strategy to increase compost suppressiveness. Disease suppressiveness of sterilised compost was restored by the addition of T. viride TV1 (> 4 g l -1 ) in P.ultimum/cucumber and in P. nicotianae/tomato. This study represents a further step toward the development of a substrate able to control a wide range of soil-borne pathogens and in the use of fortified composts for controlling plant diseases.

Antagonistic Efficacy of Trichoderma harzianum and Bacillus cereus against Ganoderma Disease of Oil Palm via Dip, Place and Drench (DPD) Artificial Inoculation Technique

“…Hence, this BCA would be the most preferred component in an amendment of a biological control compost or biofertilizer. According to Pugliese et al (2011) and Harman et al (2004), Trichoderma as a component in compost could lead to a substrate with broader-range suppressive effects. However, this present study demonstrated that consortium of T. harzianum and B. cereus was less effective in controlling Ganoderma disease of oil palm at nursery trial compared to individual application of the BCAs.…”

Manipulating the soil microbiome to increase soil health and plant fertility

“…This combination of beneficial microbes also had the added effect of stimulating plant N and P absorption (Hernandez and Chailloux 2004). Formulations of compost with beneficial bacteria have also shown the ability to suppress plant pathogens (Pugliese et al 2011;Yang et al 2011). The ability of formulations of multiple beneficial microbes to increase plant productivity and health hint at the potential of the entire microbiome and plants working together with mutually beneficial outcomes.…”

Enriched cocoa pod composts and their fertilizing effects on hybrid cocoa seedlings

“…Enrichments in composting improve nutritive value; augment disease suppressive activity and beneficial microbial populations in the composts (Postma et al 2003;Biswas and Narayanasamy 2006;Pugliese et al 2011;Diaz et al 2011;Singh and Amberger, 1995;Nishanth and Biswas 2008;Biswas 2011;Meena and Biswas 2014). Such enriched composts partly substitute mineral fertilizer requirements (Adamtey et al 2009), improve soil organic matter stocks, augument soil quality and most importantly prevent loss of nutrient N through volatilization (DeLaune et al 2004;Steiner et al 2010).…”