Skip to main content

Boosting Crop Growth using Natural Product and Synthesis Enabled Solar Harvesting

Periodic Reporting for period 2 - BoostCrop (Boosting Crop Growth using Natural Product and Synthesis Enabled Solar Harvesting)

Reporting period: 2020-01-01 to 2021-06-30

A major challenge in the twenty-first century is to increase global food production to feed a continuously growing population while the quality and quantity of arable land is diminishing. Central to this problem is the necessity to increase the yield of numerous important crop species and to find ways to extend geographical locations suitable for agriculture. Cold stress is an environmental extreme that hampers crop yield. Low temperatures restrict plant growth and development, while frost causes tissue damage. Yield losses are even more severe when cold stress occurs during the reproductive stage. Breeding programs for new tolerant varieties are diverse and usually tailored to the specific needs of a particular crop. The plant's response to cold stress, however, is complex, involving many physiological, structural, and biochemical changes, which interact with other environmental factors and metabolic processes. BoostCrop represents a novel approach to improve crop yields by protecting plants from cold stress and stimulating their growth under a range of growing conditions. The invention is based on 'molecular heaters'; nature-inspired molecules that absorb light of energies that are either harmful to the plant or not used in photosynthesis, and converting this light energy to heat.

BoostCrop’s long-term vision is to develop a suite of molecules for localised heat generation for Food Security. The entirely novel and ambitious research programme of BoostCrop, which surpasses substantially any technological paradigms currently in existence, employs a bottom-up approach to engineer light-to-molecule heaters to optimise the absorption of selected components of the solar spectrum. In so doing, the ‘holy grail’ of BoostCrop is to use these revolutionary light-to-molecule heaters in a foliar spray to enhance crop growth at low temperature and high ultraviolet exposure, enhance crop yield at high crop density (conditions which result in a reduced ratio of red to far red wavelengths; low R:FR), and concomitantly reduce greenhouse energy costs. To achieve this vision, BoostCrop brings together a team of scientists with expertise in broad areas of the physical and biosciences. The radically-new science-enabled technology that the project will engender involves: (1) Guiding the flow of photon energy in molecules; and (2) Utilising this energy to combat continual European and Global challenges, first and foremost, in sustainable Food production, as well as improvements in both Healthcare and clean Energy production. The combined efforts of the BoostCrop Team , which combines the expertise of 6 participant universities with 13 university based lead investigators, one government institute with one section leader, one SME with two group leaders (see Section 4) and encompasses the 3 major disciplines of Chemistry, Physics, Biology, to create a highly efficient, environmentally friendly and affordable foliar spray for crop growth enhancement and thus sustainable Food Security.
Using sustainable processes to synthesise two families of 'molecular heaters', one being sinapoyl malate analogues (SMs) and the other being diketopyrrolopyrrole analogues (DPPs):
We have been able to constitute a library of more than 60 compounds, with optimized novel green synthetic pathways at the multigram scale.
Results obtained by our analytical colleagues with these samples continuously dictate the choice of the new SM analogues to be synthesized. For instance, we are currently synthesizing novel SM analogues with tunable hydrophobicity to improve their formulation and thus ease their application on the leaves.
Ongoing production and optimization of existing analogues for field and greenhouse testing.
Ongoing development of DPPs, though the SM family currently shows the most promise and is the main focus of the following tests as outlined below.

State-of-the-art analytical experiments to understand the light-molecule interactions that change their efficacy as a 'molecular heaters'.
We have been able to understand key relaxation pathways (excited-state dynamics) in a number of our model molecules.
Some show very good characteristics and some only suitable characteristics.
Further studies to help us understand how we can manipulate these relaxation characteristics will help inform the synthesis of new molecules and the formulation of the product.

Development of models for excited-state dynamics:
We continue to perform electronic structure calculations in the gas phase and complex environments of the candidate ‘molecular heaters' to better understand their photophysics and photochemistry. These calculations are run in synergy with experiments carried out by co-workers.
We have been able to predict relaxation characteristics and reactivity of synthesised molecules to inform the synthesis of new analogues before this work began.

By-product and toxicity analysis of our molecules:
Initial screening of candidate molecules for potential toxicity using in silico methods indicate that none of our molecules should exhibit mutagenicity or carcinogenicity.
This allows us to continue developing candidate molecules with a very high degree of assurance of their safety for food production.
Importantly, there are 3 new candidate molecules that have passed all initial safety tests.

Thermal imaging and biomass measurements in the lab, greenhouse and field:
We have successfully demonstrated that a significant thermal increase to both plant and leaf, occur following application of the molecule and under UV-A/B radiation.
There are 3 candidate molecules that show better heating than our first prototype.
In tests using a mixture of our standard SM and a "sticker" adjuvant on tomato, benth and pepper plants, we have repeatedly observed an increase in dry plant weight, up to 12.3% for our most successful case.
These tests have also highlighted that formulation is essential to optimise the growth-enhancing effects of SM and our ongoing work is focussed on successful formulation of a prototype product to conduct trials in greenhouses and fields.
Agriculture is a crucially important subject for the EU (and Globally): almost 40% of the annual EU budget is spent on agriculture. The world-wide market for agrochemicals in 2015 was estimated to be €179 Billion, of which Europe accounts 11%, while the US (59%) and Asia (22%) dominate the market (www.marketsandmarkets.com). Clearly, there is lots of room for the EU to improve its Global leadership in this sector. Cold and freezing stress are important constraints for crop and horticulture. BoostCrop's invention on 'molecular heaters' to increase crop yield during cold stress, to extend growth seasons, to expand the geographical locations suitable for agriculture (e.g. to higher altitude) and to increase crop yield at high crop density, will have a major impact, globally. In addition, the envisioned reduction in greenhouse energy costs would be immense; an industry-sized greenhouse with a surface coverage of 40000 sq. ft., would result in a saving of ~€3k (per month) on heating. This estimate assumes propane as fuel to maintain a greenhouse at 17 ºC, with an average outside temperature of 0 ºC, and molecular heaters achieving a (not unrealistic) 3 ºC temperature rise.
BoostCrop Consortium Logo