Fertilizer International 509 Jul-Aug 2022
31 July 2022
Levity Crop Science: growing more with less
COMPANY PROFILE
Levity Crop Science: growing more with less
The overuse of limited natural resources and excessive contributions to climate change are just two of the criticisms currently levelled at global agriculture. Plant scientist David Marks is addressing these criticisms head-on through the company he founded, Levity Crop Science. He believes that, with better access to the right products, farmers can bring agriculture back into balance.
“Most farmers don’t want to use harsh chemicals if they can help it. And whatever chemicals they do use, they want to minimise what they need to apply.”
It’s on this principle that Dr David Marks founded his UK-based ‘functional fertilizer’ company, Levity Crop Science. The company’s ethos is to make crop production more sustainable, without compromising yield, production or quality, and – crucially – make more efficient use of the planet’s limited resources.
“When it comes to crop nutrition, a lot of our thinking and practices haven’t really kept pace with other technologies and agricultural advances,” Dr Marks says. “The approach, because it’s what has always been done, is that if we supply the right nutrients onto the crop, they’ll find their way into the crop.
“But this can be wasteful. Look at the example of nitrogen. First, we persist in talking about ‘nitrogen’, when in fact we should be talking about a range of nitrogen-containing molecules, each of which is used differently by the crop.
“And second, too often we don’t distinguish between those different molecules – nitrate, ammonium, amine – and their optimum time for application, so a lot of the nitrogen applied to crops ends up not in the crop but in water and the atmosphere. On average, growers apply two-thirds more nitrogen than the crop receives.”
With current supply constraints and fertilizer prices reaching record highs in March, it’s a practice that farmers can ill afford at present. It’s not just nitrogen either. Dr Marks also draws attention to the “sheer unsustainability” of triple superphosphate (TSP) – a form of phosphate from which, he says, crops extract as little as four percent.
Bioactive benefits
In pointing out the shortcomings of applying fertilizers in forms that crops cannot use efficiently, Dr Marks is not simply sniping. To his credit, he’s used this critique as a springboard for positive action, by developing crop nutrition products that allow crops to make better use of the nutrients they contain (see box).
“They’re what we describe as ‘bioactive’ compounds,” he explains. “Plants are very complex structures, underpinned by sophisticated biochemistry to make them grow and flower, and produce leaves, fruit, tubers, nuts, seeds – the basis of all food on our planet.
“When we apply a crop nutrition or crop protection product, it’s usually this chemistry we seek to interact with for the applied product to take effect.
“Most nutrition products are passive, reliant on uptake through roots or leaves to be transferred to the plant’s transport system. But plants treat each nutrient differently. Some, like calcium, can only move upward through the plant. Unfortunately, that means an awful lot of foliar calcium applications are largely wasted, because the calcium stays in the leaves and doesn’t move around the plant.”
The first objective of Levity’s research is to understand the behaviour of different nutrients within the crop. Armed with this information, Dr Marks’ team can then identify the biochemical pathways responsible for nutrient uptake and transport.
But that’s only the beginning. What then follows is an extensive search to find compounds that can either stimulate nutrient uptake – such as the company’s LoCal calcium technology – or improve transport within the plant itself. An approach Dr Marks describes as ‘supercharging’ the plant’s existing metabolic pathways.
“We know farmers are frustrated,” acknowledges Dr Marks. “Crops often don’t respond to these very simple trace elements and micronutrients, despite their influential contribution to overall and marketable yields.
“Our approach is to alleviate that frustration, while also improving resource use efficiency. We get the plant to do the heavy lifting – by using existing pathways to help the crop to help itself. That’s why we use the bioactive moniker, and why we call our products ‘smart’.”
But it’s not just about resource use efficiency. While that’s a prime driver for Levity’s products, Dr Marks comes back to his point about ‘harsh’ chemicals.
“There’s an increasing acceptance that a well-fed plant is a healthy plant. Just as in humans, failure to observe a balanced diet not only inhibits some of those pathways, but also lowers the plant’s defences.
“In addition, most of the commonly applied nitrogen fertilizers favour vegetative growth, which can make plants weak and more susceptible to diseases. In turn, that might necessitate a fungicide programme to control disease or, more commonly, a growth regulator to stop the plant’s ‘legginess’.”
Dr Marks believes that taking more appropriate steps earlier, such as choosing the right form of nitrogen, could reduce the need for such interventions. Growers would benefit, with crops requiring fewer inputs and less complicated plant protection programmes. He also highlights the concerns around dwindling active substances and the ever-present threat of resistance development.
Export oriented
While active in the UK, most of Levity’s customers are found in global markets. Exports account for more than 70 percent of company revenues, with products distributed across the Americas, Africa, the Middle East, the Far East and Australasia, in addition to its ‘home turf’ in Europe.
“It’s a real adventure and a great privilege to be able to help the farmers that grow the world’s food,” says Dr Marks. “Levity’s products are used not only on staples such as wheat and rice and potatoes, but on many other economically significant crops – soft fruits, citrus, tomatoes, cocoa, for instance – to help deliver more, higher quality produce, closing the gap between potential and average yields, and helping the environment at the same time.
“With an additional 2.5 billion mouths to feed globally by 2050, it’s essential that we find new ways to increase crop yields and make the agricultural sector as efficient as possible. The importance of resilient supply chains has been thrown into stark relief after the twin ‘black swan’ events of Covid and the Ukraine invasion.”
“On top of that is the growing threat and uncertainty of climate change. If global temperatures rise as anticipated, crop growing will become more difficult – that’s why many of our products also focus on alleviating plant stress.”
Prestige research centre
It’s against this background that the company has recorded year-on-year growth of 40 percent, despite the pandemic’s well-publicised effects on global shipping and logistics. These export successes, coupled with Dr Marks’ ambition to increase the flow of products through the company’s development pipeline – he already holds more than 30 patents – are now taking shape in the form of a new company HQ and crop science research facility in northern England.
The multi-million-pound investment, which is due to break ground imminently, will give Levity several new glasshouses and research laboratories, plus a new head office and a ‘showcase space’ where the company’s products and technologies can be demonstrated to customers.
“The whole set-up will be tailored to the development of smart fertilizers and on completion will stand out as one of the best fertilizer research facilities in Europe,” says Dr Marks. “While that 40 percent growth may have been unprecedented, we still have many countries where we’d like to be present but haven’t yet been able to identify a distributor – our products are increasingly in demand.
“With the new facility will come more staff, both R&D and commercial, and we’ll be able to make more of that growth opportunity.”
Diverse product offering
Distributors are keen to stock Levity’s product range, reports Dr Marks, because they value its diversity. “We hear feedback that not only does it fill important gaps in their portfolios, but growers like the products because they can see clear results.
“That’s very important. Too many crop nutrition products, particularly those targeting trace elements and micronutrients, are not built on sound science.
“They’re also very wasteful – yet, with the right science, we can be measuring crop nutrition in grams, not kilograms. Agriculture can’t afford to be wasteful, neither with the food it produces nor the resources it uses,” he concludes.
Matching products to nutrient behaviour
Understanding how nutrients behave within the crop is the starting point for Levity’s products.
Calcium
Calcium gives cell walls rigidity and strength, providing protection from physical damage as well as a first line of defence against fungal and bacterial pathogens. Calcium deficiency is behind diseases such as bitter pit in apples and cavity spot in carrots. Strawberries low in calcium exhibit reduced shelf life and brix, for example, and are prone to mould.
Unlike most nutrients, calcium only moves upwards through the plant. It’s transported to the leaves when absorbed through the roots, while foliar applications go no further than the leaf. Complicating things further, calcium absorption by plant cells requires high levels of the hormone auxin.
Levity’s LoCal technology contains a naturally occurring ‘calcium transport stimulant’ which mimics auxin and therefore promotes calcium uptake.
Boron
Many crops are heavily reliant on boron for yield, quality and plant health. Because it’s readily absorbed and stored, tissue testing often indicates ample levels. But transport issues, again, make plant utilisation difficult, as boron’s mobility varies between crops, and even according to the crop’s growth stage. This immobility can encourage over-application – with a fine line between boron deficiency and toxicity.
Levity has formulated a low-rate boron product to avoid phytotoxicity. This is coupled with a specially developed stimulant that triggers the plant to use and direct boron according to need (Fertilizer International 504, p28).
Silicon
This element is implicated in several metabolic functions, such as hormones and biotic stress protectors, as well as plant structures. Recent research has also revealed silicon’s role in unlocking the yield potential of crops. It’s instrumental in the distribution of phosphates, zinc, manganese, iron and copper, for example, and improves nitrogen recovery in low-availability situations.
Plants also use silicon for physical protection, building a thin layer of ‘opal’ crystals within the leaf cuticle. Once deposited, this silicon becomes biologically inactive. The challenge, then, is to encourage the plant to use the silicon before it’s locked away. An added obstacle is that silicon isn’t mobile in the phloem, so it must be actively moved in and out of the xylem.
Levity embarked on what was to become a 12-year research programme on silicon, identifying the substances responsible for its transport and then emulating them. The resultant Si-X technology has demonstrated a yield response of up to 1.2 t/ha in wheat trials.
Nitrogen
Extra to its calcium expertise, Levity is also an acknowledged leader in nitrogen efficiency. The company is encouraging growers to think about the type of nitrogen they apply – nitrate, ammonium, amine – not just the quantity. Because all forms of nitrogen degrade to nitrate after application, most research focuses on nitrate uptake and utilisation. However, when the plant absorbs nitrates, it must expend energy to convert it back to ammonium to synthesise essential compounds such as amino acids and chlorophyll. Nitrate applications can also be wasteful, being susceptible to volatilisation and leaching.
Applying the right nitrogen product at the right time, as well as being more usable by the plant, can influence the right kind of growth, such as grain fill over height in cereals, root and tuber development over top growth in potatoes.
Levity’s LimiN nitrogen technology delivers amine direct to the plant and, by using stabilised amine urea, prevents its breakdown to nitrate. LimiN features a cross-linkage between the NH2 amine and a monovalent or divalent cation which renders the NH2 nitrogen invisible to soil bacteria. This allows growers to apply less nitrogen but achieve the same results.
Manganese
This is an essential element for chlorophyll formation. Deficiency manifests as pale green leaves and reduced photosynthesis capacity. Levity’s scientists have combined their LimiN technology with another in-house development, known as Catalyst, to promote the uptake and usage of manganese. This approach enables crops to develop an optimised structure for light capture and to sustain this over an extended period.
Molybdenum
Molybdenum is essential for nitrogen processing and fixation. It’s also a component in abscisic acid (ABA) which, alongside ethylene, is the hormone involved in fruit ripening. Unfortunately, ethylene ripens fruit by removing calcium from the cell wall, leaving softer fruit more susceptible to damage, while – advantageously – ABA is able to lift brix and colour without affecting softness. Nevertheless, ethylene will control ripening if the plant’s molybdenum levels are low and therefore insufficient ABA is available.
Levity’s solution was to use a ‘building block’ formulation to encourage the plant to make better metabolic use of molybdenum. By applying this micronutrient in ‘supercharged’ form, the plant is forced into using molybdenum to produce ABA as soon as the fruit enters its maturation phase.
Iron
This is another constituent of chlorophyll and is also involved in several metabolic functions. Iron can often be a problem for farmers on calcareous, high pH soils. Deficiency displays as chlorosis – yellowing leaves – due to poor chlorophyll production. Growers are typically encouraged to use iron chelates to make iron available to the crop.
A strong link, however, exists between nitrogen inputs and iron deficiency. That’s because iron is used as an enzyme co-factor when plants reduce nitrates to proteins. As a consequence, crops can use up to 70 percent of their iron in nitrate processing.
Levity’s approach involves reducing the plant’s need for iron by improving its harvesting of locked-up iron instead. Stabilised amine nitrogen was again the solution – as this allows iron to be reserved for other uses by cutting the plant’s need to process nitrates. Moreover, linking the iron to the stabilised amine means that the plant pulls in iron alongside the amine. Finally, supplying nitrogen in amine form also improves the crop’s access to other nutrients by promoting better root development.
