Empa study – positive impact of Trichoderma on root nodules

In a Master’s thesis at Empa, Robinia (Robinia pseudoacacia) was examined for its root nodules. Root nodules are formed by the symbiosis of Robinia roots with the bacterium Rhizobia. These bacteria help the tree to fix nitrogen. The nodules are perennial and can grow up to 10 mm in size.

The Robinia trees were treated with Trichoderma After 19 weeks, the roots were excavated and checked for root nodules. The control trees without Trichoderma showed smaller and a lower number of root nodules compared to the Trichoderma treated trees. This showed that Trichoderma has a positive influence on the number and size of root nodules. It can be concluded that these trees are able to fix and absorb more nitrogen than the control trees.