Biochar as a carrier: Trichoderma harzianum on Biochar to promote disease suppression in strawberry

For the ministry of economic affairs, ECN (Energy Centre Netherlands, part of TNO) develops energy production from renewable organic sources. Pyrolysis and gasification are technologies by which green bio gas and platform chemicals can be produced. Another option is to co-produce bio-energy and biochar. Biochar is the high-carbon low-solid product of the process. The economic feasibility of the latter processes dependents on the valorisation of biochar. A promising application is as (partial) peat replacement option in potting soil mixtures for greenhouse horticultural production. Wageningen University & Research Greenhouse Horticulture used biochar in dedicated research to accomplish two distinct goals. The first goal was to use biochar as an environmentally more friendly peat alternative in potting soil mixes for the production of strawberries. The second goal was to use biochar as carrier for beneficial micro–organisms for the production of strawberries. In a cultivation experiment the growth effects in a range of biochar–peat mixtures was studied. Trichoderma was added to protect the plant against a wilful addition of the disease Phytophthora. The results show 10, 20 and 30% v/v of biochar in a peat soil does not affect fresh or dry weight production of leaf and stem mass. The biochar addition does increase the fruit fresh weight production with about 5-10%. The addition of Trichoderma with biochar did not lead to an improved survival of the Trichoderma in the potting soil mixes. The added Phytophthora did not lead to a higher disease incidence, but the Phytophthora presence is lower in treatments with a higher dose of biochar.