The benefits of boron

Omex MDS coatings

Boron is required for crop growth and reproduction. Deficiencies affecting more than 100 plant species have been reported in over 90 countries globally. Andrew Lawrence, export manager for fertilizer coatings at Omex Agrifluids, explains how boron deficiency and its impacts can be addressed.

During the early stages of crop development, boron deficiency will retard new growth and the development of roots, with symptoms usually showing in young leaves initially. As the crop develops, boron deficiency has clear negative effects on flowering response and pollination, leading to reduced seed, tuber, or fruit set. Maturation is often delayed, while reduced starch accumulation slows crop development and greatly increases the risk of structural problems in seeds and fruit. Boron deficiency is also associated with reduced tolerance to drought and heat stress, two factors which are likely to become more frequent due to climate change.

Hence, boron, alongside other nutrients, is acknowledged as being important to crop health. Calcium is another essential nutrient with a vital role to play in cell growth, development and tissue protection. By combining calcium with boron, to further enhance pollen tube elongation, it is possible to promote successful pollination and, crucially, avoiding unnecessary abortion of flowers. Recent product research by Omex Agrifluids has confirmed the important nutritional inter-relationship between boron and calcium. This realisation has enabled the company to move away from straight boron products and provide growers with more advanced product solutions that address broader nutritional requirements throughout the crop cycle.

It is well understood that addressing any lack of boron at the earliest possible stage of plant development pays dividends later. With this in mind, Omex’s calcium enriched MDS Boron product allows growers purchasing granular fertilizer to apply boron as a fertilizer coating saving time and effort during the planting season.

The application rate of MDS Boron (8% B w/w) can be quickly adjusted to correct any specific deficiency identified by soil testing, allowing custom applications to be easily applied while controlling input costs. As the crop advances, Omex Calcium Boron (15% Ca & 3% B w/v) and the solution fertilizer Omex Foliar Boron (11% B w/w with nitrogen) can be very effective at correcting any remaining deficiencies, especially during times of environmental stress.

MDS coatings are typically concentrated suspensions specifically formulated to evenly coat the surface of each fertilizer granule. These coatings, by providing accurate field distribution, make vital nutrients available at the earliest stage of crop development. Omex MDS coatings are very easy to apply commercially with existing blending equipment. Additionally, at small holder farm level, the manual coating of fertilizers is also possible with only minimal investment in equipment required.

Omex MDS coating products include the full range of micronutrients and are compatible with a wide range of granular fertilizers – including NPK blends, compounds, and straights. Furthermore, trace micronutrients, typically selenium, cobalt and molybdenum, can also be included with MDS for a safe and accurate application to fertilizer materials.

Maximising boron efficiency with Wolf Trax®

The coating product Wolf TraxBoron DDP® ® offered by Koch Agronomic Services (KAS) can supply boron efficiently to crops around the world, as Matias Ruffo, the company’s senior agronomist for Latin America, explains.

Globally, boron is the second most widely used micronutrient and can have a direct economic impact if a crop experiences a boron deficiency. Due to its behaviour in the soil and crop, it can be a difficult nutrient to manage. Much like other micronutrients, boron faces similar challenges when it comes to segregation and lack of uniform distribution when applying granular micronutrient fertilizers alone or in bulk blends.

For most crops, boron is immobile within the plant which means the best way to supply boron to meet crop demand throughout the season is through root uptake (soil application). In contrast to its immobility in the plant, boron is very mobile in the soil and can be lost due to leaching, especially in sandy soils, high rainfall areas or under irrigation. This makes it challenging to supply boron over the entire growing season (and typically requires annual applications). Since plants are not very effective in regulating boron uptake, there is a very small range of optimal boron availability because high soil boron concentrations can result in phytotoxicity. This makes it critical to have a uniform boron distribution across the field.

To help address these management challenges, Wolf TraxBoron DDP® ® (dry dispersible powder) is one solution capable of efficiently supplying boron to crops around the world. Wolf Trax Boron DDP features three exclusive proprietary technologies, Evencoat® , Plantactiv® and Dual Action, that help to efficiently deliver the boron nutrition that today’s crops require to meet their genetic yield potential.

Boron and other micronutrients, when applied in bulk blends with macronutrients (NPKs), can suffer from segregation, resulting in uneven application rates of the micronutrient in the field. The Evencoat technology featured in Wolf Trax products ensures that boron is thoroughly and homogenously coated onto each granule of the fertilizer blend, thus eliminating the risk of segregation and its negative effects. With Wolf Trax Boron DDP, boron gets applied over the entire field at the precise and accurate rate.

Even when segregation is minimsed, bulk blends which incorporate granular boron products result in uneven distribution, with only a few granules of boron per square foot. This creates two issues. Firstly, the creation of high boron concentration ‘hot spots’ can cause phytotoxicity (which is typically not an issue for other micronutrients) where the boron granule falls. Secondly, very few ‘feeding points’ are available where roots can take up boron. This has a knock-on effect on crop nutrition – and explains why the typical boron application rate is much higher than the crop’s actual requirements.

In contrast, the uniform, even distribution of boron achieved by coating every fertilizer granule with Wolf Trax Boron DDP results in more points of interception for the plant’s roots to take up boron. This gain in efficiency allows for lower concentration rates compared to bulk blends. In addition, with Wolf Trax Boron DDP, the risk of boron toxicity is minimized as it doesn’t generate the ‘hot spots’ that can occur with bulk blend applications.

As mentioned earlier, unlike other micronutrients such as, zinc or copper, boron is highly mobile in the soil profile and can leach past the root zone, particularly in sandy soils which are also typically boron deficient. Therefore, applying a highly soluble boron fertilizer can be cause for concern since it can be lost and, in some situations, lead to toxicity. Conversely, using a less soluble boron source has the risk of not supplying the boron that rapidly growing crops demand to reach high yields. To address these issues, Wolf Trax Boron DDP is formulated to safely deliver boron to crops throughout the growing season. The technologies found in Wolf Trax products provide three forms of boron with a range of solubilities to help ensure nutrients are available when crops need it most.

To help meet crop nutrient demands, Wolf Trax Boron DDP technology also provides unparalleled flexibility when it comes to customising the formulation to suit individual fields and crops. Conversely, compound or complex fertilizers that only supply boron at a fixed micronutrient-to-macronutrient ratio make it difficult to apply boron at the right rate.

To summarise, Wolf Trax Boron DDP helps address the most critical challenges for efficient boron crop nutrition, with in-built technologies that provide value, convenience and flexibility – both to the farmer and the fertilizer blender.

A better boron boost

Too many micronutrients are over-applied and underutilised, but none more so than boron, says British plant scientist David Marks. Boron is one of the latest micronutrients to benefit from the ‘functional fertilizer’ approach developed by his company Levity Crop Science.

There is no simpler way to state it: boron is essential for healthy crops. An intrinsic part of the cell wall structure, this trace element is also vital in fruit and nut crops at flowering, pollen tube development and seed formation, for flag leaf development in cereals, and tuber bulking in potatoes.

“It’s fair to say that a great many crops around the world rely on boron for robust yields, marketable quality and overall plant health,” Dr Marks points out. “It’s not that farmers aren’t aware of the importance of boron; it’s just that many of them don’t see it as a problem, because boron’s quite deceptive once it gets into the plant.”

Crops readily absorb boron when it’s available, Dr Marks explains, after which it’s stored in leaves. “Growers are encouraged to tissue test for boron. Often the results will indicate ample boron levels, but that’s not the whole story.

“Boron’s mobility once in the plant is highly dependent on the individual crop. It can even change within the same crop according to growth stage or external environmental factors. The biggest mistake a grower or an adviser can make is in assuming boron behaves the same way, all the time.

“In avocados, for example, boron transport in the phloem relies on binding with complex sugars. But at times of stress, or when there’s a need to conserve energy for flowering and fruit development, complex sugar production is turned off because it’s carbon – i.e. energy – intensive.”

In these circumstances, despite adequate levels, boron often won’t reach the parts of the plant where it’s most needed. This either encourages over-application, either in quantity or frequency – which can be risky, given boron’s fine line between deficiency and toxicity – or no application at all because previous usage has appeared ineffective, notes Dr Marks.

Levity’s expertise is in functional, or ‘smart’ fertilizers. Designed to improve not just yields and quality or, in the case of soft fruit, shelf life and brix, its products are designed and formulated to ‘hijack’ existing biochemical pathways within the plant. Nutrients such as calcium, molybdenum and another recent new development, silicon, are notoriously difficult to manage in many crops – something that Dr Marks aims to resolve.

“Growers are encouraged to tissue test for boron. Often the results will indicate ample boron levels, but that’s not the whole story.

“There’s deep farmer frustration out there,” acknowledges Dr Marks, “that crops often don’t respond to these very simple trace elements and micronutrients, especially when they are so influential in determining overall and marketable yields.

“But with an understanding of exactly where the limiting factor lies, and how it manifests itself, we can design a product that gets the plant to do the heavy lifting, by making use of existing pathways.

Dr David Marks, founder and managing director of Levity Crop Science, inspects a UK strawberry crop.

PHOTO: LEVITY CROP SCIENCE

“Take our calcium delivery product Albina, which contains proprietary LoCal technology. It improves marketable quality and shelf life in top and soft fruit. To make that work, we created our own calcium transport stimulant that emulates the plant hormone auxin – which is crucial in calcium transport.”

Damu, Levity’s boron product, takes a similar approach. Dr Marks and his team formulated a low-rate product that would avoid any phytotoxic effects, while adding a specially developed stimulant that triggers the plant to use and direct the boron where it’s needed.

“In potatoes, for example, the best timing for Damu is during periods of excess vegetative growth, when it can ‘train’ the plant to focus on root and tuber growth instead. Meanwhile the low rate allows frequent applications to keep levels constant and replenished – allowing small amounts to be applied but ensuring highly efficient use of those applications with very little wastage.”

Already enjoying success with some of Britain’s leading potato producers, Damu is also finding favour with farmers in countries and crops beyond Levity’s British base. “Peppers, tomatoes, avocados, citrus – these are all crops in which good, well-timed use of boron can deliver good fruit set and size,” Dr Marks explains.

“What’s more, we’re doing all of this without harsh chemicals, thanks to identifying and working with the natural processes already present in the plant. It’s an aspect that resonates with more and more growers, whether through pressure from buyers or their own commitment to changing the way they farm.”