Collaborative roots could reduce reliance on phosphorus fertilisers

Farmers could improve the efficiency of phosphorus in crop production by coupling plants with complementary traits, which would allow them to harness the ‘phosphorus bank’ already present in soils.

Exploring the potential of ‘collaborative roots’ to make organic phosphorus available to plants is the objective of a new £1.2 million, three-year project undertaken by a scientific consortium including the James Hutton Institute, Rothamsted Research and led by Lancaster University.

Phosphorus is a non-renewable resource, essential for crop and food production. Due to inefficient use and limited global reserves, inorganic phosphorus fertilisers will become less economically viable and there are concerns about future supplies. Without action, this situation could undermine agricultural productivity.

A large proportion of phosphorus already present in soils is found in organic forms, which are generally unavailable to plants for two reasons: firstly organic phosphorus is often tightly bound to soil surfaces, and secondly, it must be transformed into inorganic compounds before it can be taken up by plants.

Dr Tim George, rhizosphere scientist at the James Hutton Institute and lead investigator on the project, said: “Some plants help mobilise organic phosphorus in soils by producing organic acids from their roots, whilst others exude enzymes that mineralise this phosphorus into forms available to plants.

“We are investigating bi-cropping systems that combine plants with these individual traits to determine if such systems can improve the utilisation of organic phosphorus and help transform organic phosphorus into a viable, sustainable nutrient source for agricultural production.

“Outputs from the project will have impact for many individuals involved in crop production from agricultural research scientists, fertiliser suppliers, crop breeders and land managers through to policy makers.

Professor Phil Haygarth of Lancaster University said: “By increasing the amount of phosphorus utilised from the ‘phosphorus bank’ stored in soils we can reduce the reliance on inorganic fertilisers, increasing agricultural sustainability and improving our ability to deliver food security in coming decades.

“It is exciting to be starting this collaborative project with such a strong team, we have potential to make a real difference to the future of food production.”

The results of the study could influence the way in which cropping systems are considered in the future both nationally and internationally, by providing fundamental science to support crop development, based on more than just yield and productivity, but also on the specific soil/plant processes involved.