In this study, researchers wanted to determine whether trimming of roots of young vines prior to planting affects mycorrhizal fungi on the roots.
Arbuscular mycorrhizal fungi are symbiotic fungi which are beneficial to plants by helping plants to capture nutrients from the soil. They are sometimes applied as biofertilizers to young vines before planting, with the intention to aid establishment of the vines once they are transplanted into the field. Often the roots of the young vines are trimmed prior to planting to avoid J-rooting and to ensure the roots fit comfortably into the planting hole. It is not known whether root trimming removes active mycelium, therefor losing all the benefits of the inoculation.
By means of a greenhouse experiment, researchers tested how root trimming affects mycorrhizal fungi on vine roots.
Mychorrizal symbiosis persisted on roots, despite root trimming. This is probably because the fungal structures left on roots after trimming survived and was sufficient to easily recolonize new roots that developed after planting. It is clear that the commercial isolate used to inoculate the roots is very suitable to use as inoculum on young vines, prior to planting. Trimmed vines had lower shoot biomass, but not lower root biomass.
Holland, T., Bowen, P., Kokkoris, V. et al. The effect of root pruning on the arbuscular mycorrhizal symbiosis in grapevine rootstocks. Chem. Biol. Technol. Agric. 6, 21 (2019).