The development of sustainable seed coating formulations is essential to enhance crop performance while reducing reliance on synthetic inputs. This study evaluates biochar-enriched coatings incorporating olive pomace, buffalo digestate, and microbial consortia from
Fagus,
Quercus, and
Pinus forest litters, including
Trichoderma
[...] Read more.
The development of sustainable seed coating formulations is essential to enhance crop performance while reducing reliance on synthetic inputs. This study evaluates biochar-enriched coatings incorporating olive pomace, buffalo digestate, and microbial consortia from
Fagus,
Quercus, and
Pinus forest litters, including
Trichoderma harzianum, for their effects on seed germination and plant growth. Four crops (
Diplotaxis tenuifolia,
Lactuca sativa,
Solanum lycopersicum, and
Zea mays) were tested through germination assays and field trials. Treatments containing digestate or pomace alone significantly reduced germination and seedling growth in
D. tenuifolia and
L. sativa (below 25%, compared to control), due to the phytotoxic effects of ammonia, salts, and polyphenols. In contrast, biochar-based coatings mitigated these effects, enhancing germination and root elongation. The addition of
T. harzianum further improved seedling establishment, likely by enhancing nutrient uptake and suppressing soilborne pathogens, with increases exceeding 100% (compared to control). Field trials confirmed these findings, showing that biochar–
T. harzianum combinations improved both shoot and root biomass, particularly in
L. sativa and
S. lycopersicum.
Z. mays displayed greater tolerance to raw by-products, though biochar remained essential for optimal growth. While forest-derived microbial consortia supported microbial balance, their effect on biomass was less pronounced. These results highlight the potential of biochar-based coatings, especially when combined with
T. harzianum, as sustainable alternatives to conventional seed treatments.
Full article