Fortifying fungi helps plants to thrive
Researchers have identified the type of fungi that has the most significant impact on a plant’s nutrient levels.
The symbiotic relationship between plants and fungi sees root-associated fungi provide up to 80 per cent of the nutrients and water a plant needs to grow, while plants simultaneously produce up to 30 per cent of the photosynthate food substance required for the fungi to survive.
Fungi penetrating the cells of rootsincrease nutrient concentrations
Two of the main types of mycorrhizal (or root-associated) fungi that exist are known as arbuscular and ectomycorrhizal fungi. A new paper entitled Proceedings of the national academy of sciences identifies arbuscular mycorrhizal fungi as being particularly beneficial to plants, thanks to its ability to burrow deep into the root cells. Conversely, ectomycorrhizal fungi do not penetrate the plant's cell walls, but instead form a netlike structure around the root.
Arbuscular mycorrhizal fungi were found to give a greater boost to the concentration of nutrients in leaves, litter and roots than ectomycorrhizal fungi. What’s more, root-associated fungi in general have more influence on a plant's nutrient levels than its leaf traits or associations with nitrogen-fixing bacteria.
Stephanie Kivlin, an Assistant Professor at the University of Tennessee in Knoxville and co-author of the paper, said mycorrhizal fungal associations below the ground are some of the strongest influences on plant tissue nutrient concentrations in plant tissue.
"To optimise plant nutrition, we need to incorporate mycorrhizal associations into our agricultural and management frameworks," said Assistant Professor Kilvin.
The study included in excess of 17,000 trait observations from almost 3,000 woody plant species, across six categories and multiple environments encompassing boreal, temperate and tropical latitudinal zones.
"The next steps are to understand if there is variation in nutrient acquisition among fungal species within each mycorrhizal group, and how soil nutrient concentrations may interact to influence plant nutrient concentrations with global change," said Assistant Professor Kilvin.
Trichoderma could be used to improve tree health and growth
In additional fungi-related news, research out of New Zealand has found the naturally occurring group of fungi known as Trichoderma, which also enter plant roots from the soil, can offer long-term protection from disease, as well as enhanced strength and tolerance to stress.
With promising discoveries having been made during previous smaller-scale trials, Dr Helen Whelan, of Lincoln University’s Bio-Protection Research Centre, led eight larger-scale trials in forests across the Gisborne, Northland, Bay of Plenty, Waikato and Nelson regions of New Zealand.
Seedlings treated with two types of Trichoderma, identified as particularly beneficial in the earlier trials, were planted at low and high altitudes at each trial site. The forest owners enthusiastically hosting the trials now eagerly awaiting the results.
Patrick Milne of New Zealand Farm Forestry Association and Southern Cypresses Ltd, said the research has huge potential.
“This research could be a game changer. If we can get Trichoderma to increase canker resistance — we don’t need to eliminate it all together — then that would be fantastic.”
Sources: Phys.org and Forest Growers Research