A novel biostimulant could deliver increased wheat yields of up to 12%, according to researchers from Oxford University, Rothamsted, and the Rosalind Franklin Institute in a long-term study published in the journal Nature Biotechnology. This is an order of magnitude greater than annual yield increases currently being achieved through breeding.
Applying the T6P biostimuant at a field trial at Rothamsted. Credit: Rothamsted.The biostimulant is based on trehalose 6-phosphate (T6P), a signalling molecule that regulates the plant equivalent of "blood sugar." T6P acts as a molecular switch that prompts the plant to produce more starch, the world's most significant food carbohydrate, and increases the rate of photosynthesis. It can be applied to a number of key food crops including wheat and rice.
The novel biostimulant was developed through years of collaborative research between Professor Ben Davis (Oxford University and now also The Rosalind Franklin Institute) and Dr Matthew Paul (Rothamsted). Earlier experiments in controlled environments looked promising , and this new study has confirmed that the application could deliver major yield improvements for wheat in field conditions. Overall, the treatment caused an average yield increase of +10.4%.
Professor Davis said: 'By confirming the effectiveness of this novel biostimulant molecule in the field, these results open the way towards gaining regulatory approval, industrial manufacture, and making this technology available to increase food crop production in some of the poorest countries in the world.'
The new findings are based on a four year-long field study using plots at the International Maize and Wheat Improvement Center (CIMMYT) , Mexico and The National Agricultural Technology Institute (INTA) , Argentina. Not only did T6P increase wheat yields in each of the four years in the trials in Argentina and in an additional year at CIMMYT in Mexico, but it did so irrespective of rainfall, the major uncontrolled abiotic factor that limits crop yields globally.
Wheat has complex genetics, which makes it difficult to improve yields by targeting bottlenecks through breeding. Consequently, applying the T6P biostimulant as a low-cost spray is an attractive alternative. This would not be possible with the natural form of T6P, since this cannot cross the cell membrane. The research team addressed this by developing precursors of T6P that are membrane-permeable and release T6P into the plant in the presence of sunlight.
Wheat ears and grains (left panel), and sorghum panicles (right panel) showing the yield increase caused by applications of the novel trehalose 6-phosphate-based biostimulant. Image credit: Rothamsted.
Professor Ben Davis. Credit: The Rosalind Franklin Institute.Professor Davis added: 'The development of chemistries that may be applied in living systems has been a long-standing goal of work at Oxford. This work builds on bond-breaking chemical reactions to control signalling pathways, here in a manner that is triggered simply by sunlight. This then allows the "unmasking" of a key part of the applied pre-signalling molecule at just the right rate to trigger an effect in plants.
'We also designed a new synthetic chemical production route, which generated intermediate molecules in a crystalline form. This ultimately enabled industrial-scale manufacture that allowed these field trials to go ahead, by producing the biostimulant in larger quantities. We believe that it suggests a new path for sustainable agriculture.'
It may even be possible to reduce fertiliser applications as T6P treatment also activates genes for amino acid and protein synthesis in grain. This is important because a major issue in new higher-yielding wheat varieties is protein content becoming diluted. This means that more fertiliser is then required to maintain the quality needed in, for example, bread making.
This work provides an excellent example of a case where manipulating a natural molecule, rather than using genetics or gene editing, is a game changer. It has been very inspiring to design and discover this new class of "drug for plants" together.
Professor Ben Davis, Oxford University
With no similar products currently on the market, Oxford University and Rothamsted created SugaROx , a spinout company, to deliver this research to farmers.
Dr Cara Griffiths, lead author of the research paper and now CSO of SugaROx, said: 'It's exciting to be able to take cutting-edge technology from the bench to the field. Getting this kind of impact is often difficult to translate to the field, and this work demonstrated that novel crop inputs have huge promise to enhance yield and resilience in our cropping systems, something that is particularly important in a rapidly changing climate.'
The study 'Membrane-permeable trehalose 6-phosphate precursor spray increases wheat yields in field trials' has been published in Nature Biotechnology .
