Cultivating high value fungi in future tree orchards

The majority of plants have a symbiotic relationship (mycorrhizae) with a type of soil fungi known as mycorrhizal fungi. These mycorrhizal fungi colonize the plant roots (a bit like a glove covers fingers) and supply their host plants with water and nutrients and in return plants supply soluble sugars to the fungi.

Some mycorrhizal fungi (forming ectomycorrhizae) produce large fruiting bodies – mushrooms (above ground) and truffles (below ground), many of which are edible. Market supplies of most mushrooms are from natural populations, as only a handful of edible mycorrhizal mushrooms have been successfully cultivated. However, controlled propagation of mushrooms in tree orchards is possible and has the ability to deliver high value fungi crops.

A long-term collaborative study between scientists at Plant & Food Research and the Chinese Academy of Science, assessed the feasibility of controlled colonisation between five native Chinese milk cap mushroom species and five pine species. The colonised pines were maintained under glasshouse conditions for up to 14 months until the mycorrhizae were abundant and dominant on the root systems. This first step in cultivation (known as “marrying”) is critical to ensure seedlings are fully colonized before outplanting.

The scientists found that an inoculation method based on pure cultures of fungal tissue led to high levels of colonization for 13 combinations of pines and fungi species. Promising combinations were identified for cultivation trials in the field, providing a foundation for the establishment of future mushroom orchards. 

The study also found control of insect grazing during the cultivation stage in glasshouse conditions will be critical to large-scale production of mycorrhizal-colonized seedlings.

This work was supported by the following projects: Visiting professorship awarded to Dr Alexis Guerin-Laguette under the Chinese Academy of Sciences President’s International Fellowship Initiative, Program of High-End Foreign Experts Affairs of China, National Key Research and Development Program of China, and Science and Technology Research Program of Kunming Institute of Botany–CAS. 

Journal Reference:

Wang, R, Guerin-Laguette, A, Huang, L, Wang, X, Butler, R, Wang, Y, Yu, F. 2019 Mycorrhizal syntheses between Lactarius spp. section Deliciosi and Pinus spp. and the effects of grazing insects in Yunnan, China. Canadian Journal of Forest Research 49. DOI: 10.1139/cjfr-2018-0198