Rapid growth of Trichoderma

Trichoderma are soilborne fungi that occur worldwide. Urban soils often have less microbial activity than compared to naturally formed soils due to their lower organic matter content. One way to increase the amount of beneficial microorganisms and to restore the imbalance is the use of Trichoderma.

Trichoderma are characterised by a short life cycle and high growth rates of up to 2 cm/day under optimal conditions. In comparison, growth rates of e.g. basidiomycetes (fungi, department showing the most frequent pests on trees) are usually 1 to 2 mm/day and life cycles range from 1 to several years.

The optimal conditions for growth and germination are temperatures between 20 and 25 °C. The conidia (asexual spores, see Figure 1) are green-pigmented and can survive cooler temperatures (e.g. in winter) in which they rest until temperatures are increasing again (approx. 12 °C for growth and germination). Trichoderma itself feeds on dead organic matter, on substances excreted from roots or by mycoparasitism of other fungi.

Conidia

The green-pigmented spores of Trichoderma harzianum are asexually formed by the transformation of special hyphae. They serve as spreading organs for asexual reproduction. Source: Empa.

Mycoparasitization

Trichoderma itself feeds on dead organic matter, on substances excreted from roots or by parasitising other fungi. Source: Empa.

Growth behaviour of Trichoderma harzianum in comparison to Armillaria mellea (honey fungus) over 4 weeks.