摘要：Biochar (BC) and hydrochar (HC) are solid by-products obtained through, respectively, pyrolysis and hydrothermal carbonization of biomass. Both materials are used as organic amendments allowing carbon sequestration in soil. Two BCs, from spruce pellets (BC_(SP)) and grapevine pruning residues (BC_(GV)), and two HCs, from urban pruning residues (HC_(UP)) and the organic fraction of solid urban waste (HC_(SU)), were tested at concentrations of 0.2 and 1% (w/v) on soil-resident fungi. The higher dose of BC samples significantly reduced mycelial growth of the phytopathogens Rhizoctonia solani and Botrytis cinerea (up to 53% for BC_(GV) on B. cinerea after 24 h from inoculation, compared to control), whereas, in general, the lower dose of both BCs inhibited R. solani for the whole experiment and B. cinerea only initially. HC samples evidenced a general lower toxicity on the two pathogens than BCs. In fact, only HC_(UP) at both concentrations reduced hyphal elongation of the sole B. cinerea for the entire experimental time (up to of 38% for both doses at 24 h from inoculation). All BC and HC treatments at the lower concentration did not influence or greatly stimulated the antagonists Tricho- derma harzianum and T. virens, Differently, the higher dose of these materials caused some suppression at the initial stage or at each sampling by BC_(SP) on T. harzianum and HC_(UP) on T. virens. The whole results obtained indicate a plant protective activity of these materials with consequent less need for fungicidal treatments.
