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By Dr Niki Rust, Research Associate, Centre for Rural Economy, Newcastle University – December 2018 issue

We all know that some parts of the UK are getting more and more water- and nutrient-stressed over time. With less predictable rainfall, extended periods of droughts or heavy rainfall, and declining nutrients in some soils, it is becoming increasingly difficult for farmers to grow crops in a similar manner to what they had done in the past. To keep up with this changing world, we are finding that we ourselves are having to change.

Historically, when crops have not had enough nutrients, we’ve turned to inputs like fertilisers. However, with increasing costs coupled with more restrictions on their use – and more regulations likely in the future – we’re having to innovate to find ways to improve nutrient-use efficiency of our crops. In terms of water, irrigation is one way to get around lack of water in the soils, but it is harder to deal with too much precipitation from rainfall. Some scientists have predicted that UK weather will become more unstable in the future, with more frequent outbursts of heavy rain followed by extended droughts. How we deal with these challenges whilst keeping farming profitable and productive still remains somewhat of a mystery.

Like farmers, the European Union is concerned about how to continue producing enough food for our population in these uncertain times. It has therefore provided funding for research into methods to improve water-use efficiency (WUE) and nutrient-use efficiency (NUE) for a number of staple European crops. SolACE is such a project, which stands for Solutions for improving Agroecosystem and Crop Efficiency for water and nutrient use. This cross-disciplinary and collaborative research involves natural and social scientists, crop breeders, farming organisations and other agricultural stakeholders from across Europe to develop and test methods that improve crop production in areas of water- and nutrient-stress.

The techniques we are testing include microbial inoculants, cover crops, genotype mixtures, hybrids, fertiliser additives, participatory breeding, decision support tools to improve WUE and NUE, and conservation agriculture based on minimum/no till. We are running controlled experiments at field stations in five countries alongside on-farm trials in seven countries to test how these techniques affect WUE and NUE in durum wheat, bread wheat and potatoes.

As part of the project, we want to learn from crop producers about what they think encourages or discourages uptake of practices that can improve their crop’s WUE and NUE, as well as what methods you currently use to deal with these issues. We are especially interested in hearing what you think will incentivise uptake, such as changes in policies, taxes, subsidies, regulations or education campaigns and knowledge transfer exchanges. We are running a short, 10-minute online survey to collect your views on this. The survey can be accessed here: https://goo.gl/ forms/NX5TkN7F1O5Csv1e2 or by using the QR code below. Please do feel free to share this survey widely with your farming contacts. 

If you’d like more information on the project, you can access our website here: http://solace-eu.net and you can get more involved by joining our Stakeholder’s Forum https://www.solace-eu.net/getinvolved.html If you have any comments or questions on the survey, please feel free to contact me at niki.rust@ncl. ac.uk and I would be more than happy to hear from you.

By Sarah Ferrie, Marketing Manager at Interagro (UK) Ltd

Could amino acids be one of the most overlooked assets in plant nutrition? In this feature we take a look at how supplementing the crop with amino acid biostimulants in-season not only boosts plant health and development, but can also help crops reach their genetic yield potential.

On a cold wet day in summer 2017 we got our first insight into the real power of amino acid biostimulants. A crop of sugar beet on its last legs from a herbicide contaminated spray tank, had totally recovered following a single application of Bridgeway. As the agronomist put it, “it was nothing short of a miracle.” The herbicide damage was so severe that some of the beet didn’t pull through, but in others, Bridgeway had stimulated a new crown to grow. That crop went on to produce larger beet that weighed in 16% heavier than the undamaged beet in the rest of the field, with the same sugar levels.

Eighteen months on, trial upon trial later, working closely with growers and agronomists to really put Bridgeway through its paces, and we are certain that feeding a crop amino acids inseason, not only improves plant health but can produce fitter plants more capable of reaching their yield potential. Deepening our understanding of plant pathology and biochemistry underpins this belief. 

What are amino acid biostimulants and why do they matter?

Biostimulants are incremental technologies to improve yield by improving plant health. They are substances with the exception of nutrients and pesticides, that have the capacity to modify the physiological processes of plants in a way that provides potential benefits to growth, development and relief from stress.

Amino acids are the building blocks of all living cells which combine together in infinite variations to produce countless different proteins critical for healthy growth and development. These proteins play a vital role in virtually every process within the plant – structural components of plant tissue; metabolic enzymes and stimulation; nutrient transport, the list goes on.

Under ideal conditions plants synthesise all 18 L-amino acids they require, which they manufacture from the raw materials carbon and oxygen in the air, hydrogen from water and nitrogen from the soil. Plants therefore depend hugely on soil nutrients. As nitrate / ammonium is one of the main elements of proteins, ag systems use nitrogen / ammonium fertilisers to replenish nutrients in the soil and aid plants in generating the needed proteins. However, these crucial raw materials can become limiting, particularly as nitrogen (and water) can either leach away in the soil or become inaccessible to the crop, as we found in many parts of the UK in 2018.

Protein deficiency in plants has huge consequences on plant health which in turn impacts quality and yield. Incapable of creating reserves, as proteins have a finite lifespan, a continuous supply of amino acids must be translated in order for plant growth and development to continue. When the raw materials to produce amino acids become limited or the crop encounters abiotic stress (such as high/ low temperatures, drought, flooding, disease/pest attacks, phytotoxicity from crop protection products) amino acid production slows and plants start to break down the proteins they have made to gain the amino acids needed to speed up recovery and repair. This occurs because the selfproduction of amino acids is extremely energy expensive and it is much more efficient to self-cannibalise than it is to synthesise amino acids from scratch.

Feeding the crop additional L-amino acids via the roots or leaf tissue inseason before, during or after a stress event ensures the plant has the necessary building blocks to prevent self-destruction and aid repair.

So, what do these amino acids do?

1. Stress defence – During periods of abiotic stress plants increase production of L-Proline to help reduce the effect and speed up recovery time. It primarily strengthens the cell wall and resistance to weather extremes.

2. Photosynthesis – the most important chemical process of plants – carbon dioxide, water and light energy are synthesized into sugars, which the plant uses as an energy source to power all metabolic processes. This process is highly dependent on the amino acids L-Glycine and L-Glutamic Acid. Both amino acids are key components for chlorophyll production which absorb the light energy for photosynthesis. Increasing these amino acids increases light absorption which increases photosynthesis.

3. Enhance nutrient uptake – by increasing the availability of nutrients to plants. Some nutrients are not available to plants due to their molecular structure, ionic charge etc. The amino acids L-Glycine and L-Glutamic acid are able to bond with these nutrients making them available to the plant. These amino acids are tiny molecules allowing them to easily move through cell membranes. Their ability to bind excess metals means they are also able to reduce metal toxicity in plants.

4. Precursors to hormones and growth factors – L-Tryptophan is involved in rooting, its required in auxin synthesis for growth and development; L-Methionine is a precursor to ethylene which stimulates ripening; L-Arginine is a precursor to cytokinin production involved in cell growth, auxiliary bud growth and leaf senescence.

5. Pollination and fruit formation – one of the most important phases of development and extremely energy intensive due to the very high levels of amino acids required. L-Histidine helps with ripening; L-Proline increases pollen fertility; L-Lysine, L-Methionine and L-Glutamic Acid increase germination; L-Alanine, L-Valine, and L-Leucine improve fruit / grain quality.

Only as a stress buster?

If crops can synthesise their own amino acids it could be argued that feeding the crop additional amino acids only makes sense to help the crop through a stress scenario.

However, crops also respond with a supplement at the critical stages of plant development, e.g. vegetative growth, start of reproduction, flowering etc. as the production of amino acids required for these critical stages are extremely energy intensive. Diverting that energy to other processes such as photosynthesis, nutrient uptake, grain fill, etc. will improve the metabolic efficiency of the plant and help the crop towards its genetic yield and quality potential.

So why Bridgeway?

For growers looking to maximise the crop’s income potential, there is no better source of amino acids. Bridgeway is a plant derived biostimulant produced to food grade quality, containing all 18 L-amino acids required by plants with a ready-to-use source of organic nitrogen.  

Feeding a crop Bridgeway guarantees the supply of amino acids for building proteins and provides the most critical amino acids in higher concentration than those biostimulants based on animal sourced protein. For example – 39% higher levels of Glutamic Acid, 33% higher levels of Lysine. Only amino acids sourced from plants can be fully assimilated by crops due to the difference in chemical structure between plant sourced (L-isomer) and animal sourced (D-isomer).

The differences don’t end there. Bridgeway is certified GM free and because it is 100% plant sourced it has full backing from the Soil Association and Organic Farmers and Growers Association for use on organic crops throughout the entire life of the crop. Amino acids sourced from animals could be contaminated with heavy metals, salmonella, E.coli and pose a threat to food chain safety. It is for this reason that animal sourced biostimulants on milling wheat were banned in 2017 by NABIM and are restricted in use by a number of organisations. Bridgeway offers not only peace of mind the crop will be able to utilise all the amino acids, it also gives growers freedom to use at any growth stage, in any crop for all end markets.

Delivering results on farm

With an extensive trial and grower programme in a range of crops, it’s clear that in the right situation Bridgeway has the potential to add in the region of 3 t/ha to a decent winter wheat crop. In 2018, two different wheat crops (Relay and Skyfall) each delivered a +2.3 t/ha uplift in yield from applications at T1, T2 and T3. Both crops were exposed to heat and drought stress after the first application of Bridgeway was applied.

Nutrient analysis carried out by the agronomist on the Skyfall throughout the growing period showed the uptake of most macro and micro nutrients was consistently higher in the Bridgeway treated areas. Sugar levels measured using a digital BRIX refractometer were 23-39% higher in their leaves at every assessment throughout May and June, indicating a healthy plant that is photosynthesising well and producing the carbohydrates in the leaves and stems which ultimately will be crucial components of yield. Despite the difficult season, the treated crop went on to produce a protein sample of 12.8% versus 11.7% in the untreated.

With a range of yield increases in different crops we are working hard to understand when, where and how best to use Bridgeway to deliver the best value to growers. Look out for the next article in Direct Driller where we’ll be sharing the results of our stress and rooting work ongoing at the University of Nottingham and offer in-season advice as spring applications get well underway.

Key takeaways:

• Amino acids are the building blocks of proteins and critical to plant health

• Proteins cannot be stored so a continuous supply of amino acids must be translated for growth and development to continue

• Plants synthesise all 18 L-amino acids in good conditions but stop under abiotic stress or if nitrogen, water or air are limiting

• Feeding the crop amino acids inseason avoids self-cannibalisation & threat to yield

• Bridgeway provides all 18 L-amino acids required by plants

• Bridgeway is approved for unrestricted use in all organic crops

• For best results apply ahead of crop stress and maintain applications at the key stages of crop development

For further information please contact stuart.sutherland@interagro.co.uk

By Mark Parker posted on June 1, 2013 | Posted in No-Till Farmer USA

Growing double-crop sunflowers with multiple species has reduced inputs and enhanced primary crop health for Kansas no-tillers Robin and Kelly Griffeth. Double crop sunflowers planted with companion crops have a triple payoff for Jewell, Kan., no-tillers Robin and Kelly Griffeth.

With 2 years of companion cropping under their belts, the Griffeths are harvesting a more profitable sunflower crop, improving their soil and benefitting the subsequent crop in the rotation. The north-central Kansas farmers follow their hard red winter wheat crop with sunflowers intermixed with as many as nine different companion species, each selected for specific attributes. Continuous no-tillers since 1995, Robin and his son, Kelly, operate 3,700 acres as they raise corn, soybeans, wheat, grain sorghum and sunflowers. They were already believers in cover crops when an unplanned “experiment” revealed companion-crop potential.

“It was a fluke, really,” Robin says. “I was planting a field of buckwheat in July 2011. I had about 4 acres left and not enough seed to finish. I hate blank spots, so I mixed up some leftover sunflower seed, winter peas, five different clovers, canola, chickling vetch, safflower and a couple of different radishes — just to bulk up the volume enough to finish.” To their surprise, the sunflowers in the companion mix yielded well, without insecticide, herbicide or additional fertilizer. “We learned a lot by watching that 4-acre patch and decided this was something we needed to research a little further,” he says.

Designer Seed Mix

Kelly came up with a companion mix for the following year — common vetch, chickling vetch, spring forage peas, winter peas, cowpeas, crimson clover, oilseed radishes, purple-top turnips, buckwheat and sunflowers. At their normal rate of 21,600 seeds per acre, sunflowers made up only about 10% of the mix. Buckwheat had the largest number of seeds per acre at 64,800, with the other species ranging from 12,500 to 17,000 — for a total of 206,924 seeds per acre. The sunflower companion mix is planted as soon as possible after harvest, generally late June to early July.

The Griffeths had been planting double-crop sunflowers in 15-inch rows to achieve a quicker canopy. That meant planting at higher populations that depressed yield. What they wanted was a quicker canopy at normal seeding rates. Using their White 6531 31-row planter — which has Keeton seed firmers and Thompson closing wheels, and is set to 15-inch spacings — they planted sunflowers in 30-inch rows with the companion mix planted in the centers as a row filler, nitrogen producer and beneficial-insect attractant.

A Great Plains CTA-4000HD drill has also been used to plant the sunflowers and companion mix in 7½-inch rows, and the Griffeths continue to experiment. In the past 2 years, they’ve planted nearly 1,000 acres of double-crop sunflowers and companion species with the planter and, last year, drilled 54 acres. “You have more control with the planter, but we’re asking ourselves if we really need a picket-row stand,” Kelly says. “As long as we get the desired number of sunflower plants, and they’re fairly well dispersed, it seems to work fine — it’s more like mimicking Mother Nature.” Seeds are planted 1½ inches deep, the optimum depth for sunflowers. This year, Robin and Kelly are going to mix all of the seed together — including the sunflowers — in the planter boxes. They don’t expect a perfect stand, but believe using a soybean planter plate and optimum air pressure will produce good results. 

Controlling Weeds

A burndown herbicide is applied after wheat harvest, and 4 to 5 weeks after emergence, the Griffeths spray Select to control volunteer wheat. “The companion crop does an excellent job of controlling weeds, and we may get to a point we don’t use any herbicide. But this is wheat country, so we have to control volunteer wheat,” Robin says. “We may add pearl millet because it will jump up quickly and out-compete weeds, then it’s killed by the Select, allowing other species to take over.” Regarding moisture competition in a 25-inch annual-rainfall environment, Robin points out that sunflower roots extend much deeper into the soil than roots of the companion species.

At harvest, the Griffeths use Lucke Manufacturing sunflower pans mounted on a rigid Case IH head, a system that has worked well. “Most of the taller plants are warm season and have been killed by frost by the time we harvest the sunflowers,” Robin says. “If a species is going to cause a harvest problem, it should be left out. The beauty of the flowers we plant is they get 6 or 7 feet tall. “I wouldn’t recommend this with a dwarf sunflower. You have to choose varieties and companion species wisely.”

Reduced Inputs

For the Griffeths, companion planting eliminates the need for an insecticide and a broadleaf herbicide — as well as an 80-pound-per-acre nitrogen application. Prior to companion cropping, a pesticide was used to control head moths. Now, the companion mix attracts beneficial insects — bees, predator wasps and lady beetles — that have successfully replaced the pesticide. At a cost of $15 to $20 per acre each for the insecticide and herbicide applications, Kelly says the companion-crop seed mix is basically paid for. The entire seed mix, including sunflower seed, costs $65 per acre — about the same cost as doublecrop soybean seed.

The primary profit impact of this comes at harvest time, Robin says. “Yields are comparable to sunflowers without a companion crop — they’re certainly not less,” he says. “The real profit advantage is grain quality. The sunflowers have better plant health, with far less insect damage and that gives us better oil content. “We’re paid a premium for high oil content, and with the companion crops, the oil premium has been the highest we’ve ever received.” Rental Income In addition to higher yields for grain sorghum and corn following sunflowers, the Griffeths may add to double-crop income by renting companion-cropped fields for winter grazing.

Kelly has taken the lead on identifying plants that contribute positively to the mix. “You have to do your homework to find out what companion species will work together,” he says. “If you look on the Internet, you’ll find most of the information comes from gardening Web sites. “You can find out which species grow together, and those that have a negative impact on each other. It’s important to avoid antagonistic combinations. You don’t just throw a random mix out there.” The Griffeths have grown doublecrop, food-grade buckwheat and believe it’s an important component. Kelly says buckwheat makes phosphorus more available for the following crop, establishes quickly and attracts beneficial insects.

Companion Criteria

There is a wide world of other species from which to choose, Kelly points out. “All species have to satisfy two criteria,” he says. “They have to be compatible with the primary crop, not detrimental. “And they have to help us accomplish something we’re after — quick weed suppression, soil building, nutrient cycling and attracting beneficial insects.” Although they continue to assess species and mixes, Kelly says one thing is clear. “I’m not sure you can get too much intensity,” he says. “If there’s been an issue, it’s because the mix is not intense enough. We had some marestail pop up here and there, for example, and we felt it was due to the companion stand not being intense enough.” 

Crop Insurance

Robin and Kelly plan to extend their companion-crop concept to corn this year. It will have to be on double-crop corn, however, since crop insurance will not cover the practice. “Making a profit is our primary purpose,” Robin says. “We take care of cash crops first, and anything we try has to pencil out. We’d love to try companion crops on full-season crops but, from a risk management standpoint, you don’t want to make an insurable crop uninsurable.” The Griffeths will plant corn in 30-inch rows with a companion mix of lupins, cowpeas and sunn hemp.

Soil Benefits The Griffeths also plant cover crops ahead of soybeans — typically cereal rye, oats, safflower and mustard, or other mixes. Continuous no-till with cover crops makes a positive soil quality impact, says Kelly. In addition to decreased compaction, reduced erosion and increased water efficiency, the Griffeths have measured rising soil organic-matter content. “We soil sampled a CRP field we’ve farmed for 3 years,” Kelly says. “Organic matter was 3.1% when we took it over and, 3 years later, it was up to 3.5%. That’s all from using cover crops and notill, and I think the companion cropping can have an even bigger impact.

How much do you really know about your soil and its health? Elizabeth Stockdale, NIAB and knowledge exchange lead for the AHDB Soil Biology and Soil Health Partnership takes a closer look.

Recent work on soil management carried out by AHDB with grower groups across the country highlighted a lack of information on soil biology and soil health. Soil physics, chemistry and biology are interlinked and all play a role in maintaining productive agricultural and horticultural systems. While physical and chemical properties of soil are relatively well understood, the same is not necessarily true for soil biology. Soils contains a very high diversity of organisms. Until recently only around one per cent of all soil micro-organisms had been identified. Soil organisms interact with one another and the chemical and physical properties of the soil to drive soil processes, such as:

• Release and recycling of nutrients

• Forming and maintaining soil structure to maintain water and aeration

• Both causing and controlling plant diseases and pests

• Nitrogen fixation or increasing nutrient availability through beneficial relationships with plant roots

Together interactions between soil physical, chemical and biological factors contribute to soil health. In the same way we measure our own health by our ability to carry out our normal everyday tasks, healthy soil can be recognised by its outputs/functions i.e. healthy plants, animals and ultimately humans.

It is useful to consider whether we can identify underlying indicators that help us identify when soil is in a healthy or unhealthy state – the equivalent of taking a soil’s blood pressure and temperature. Because of the wide range of soil types, climates and farming systems in the UK, it is important to put such indicators into context. AHDB’s GREATsoils programme pulls these three factors together and provides valuable information on soil management for growers and agronomists. Funded in 2016, the Soil Biology and Soil Health Partnership aims to fill a gap in knowledge and help farmers and growers manage soil health better.

The Soil Biology and Soil Health Partnership, 2017-2021

Funded by AHDB and BBRO, the five-year Soil Biology and Soil Health Partnership is a series of cross-sector research and knowledge exchange projects. Each is designed to help farmers and growers maintain and improve the productivity of UK agricultural and horticultural systems. The key output of the Partnership will be a toolkit including an integrated scorecard to help growers measure and manage soil health. All the outputs will be designed with farmers and growers so they can be easily understood.

The Partnership comprises eight scientific partners and six industry partners and this breadth of expertise provides a robust practical and scientific foundation. However, we recognise that farmers and growers have already taken the initiative to understand the health of their own soils and a great deal of work is already being done on-farm to experiment with ways to optimise soil biology and health.

Therefore, from its outset the Partnership has sought to work closely with farmers, growers and advisers to draw together and build on current knowledge and experience. Crucially, the Partnership will also involve key players in the agri-food sectors to direct the work and maximise the practical relevance of its findings in modern farming rotations.

Findings so far

In the first year of the programme, we have:

• Updated scientific reviews of soil biology and soil health

• Developed a model that provides an easily understood summary of the effects of soil management on soil biology and soil health

• Identified a set of methods to measure soil health on-farm which can be used to support practical decision-making

• Reviewed molecular-based 

approaches that can be applied to assess soil biological function In recent years, a range of indicators for soil biology have been developed. It is now possible to measure soil chemical, physical and biological properties. Some of the best measures of soil physical structure and its stability can be completed in the field whereas most chemical properties need samples to be sent away for analysis. The recommended biological indicators may be assessed in the field (earthworms) or sent away for analysis (soil respiration).

However, often these indicators have not been produced in parallel with the necessary guidance and tools to allow them to be easily used on farm. We have selected some indicators for testing where we will focus on whether the target values/thresholds for soils/ farming systems are correct e.g. soil organic matter levels. We are also trying out new DNA-based indicators of the soil biological community in practice. 

What next?

Over the next three years, we are working on pre-existing long-term soil management trials and on commercial farms to evaluate the performance of the model and to evaluate a new soil health scorecard. This work includes trials on raspberry, onion and narcissus. Seven long-term soil management trials have been identified which have treatments in place that target the main influences on biological function:

• Food source – nutrient and organic matter inputs, cropping choice and sequence 

• Air and water supply – tillage systems and drainage 

• Chemical environment – pH  

Across these trials and commercial farms, a programme providing detailed monitoring of crop (yield, disease and weed constraints) and rotational soil health is now in place. Soil sampling takes place in the autumn post-harvest and after the soil has wetted up. A key part of sampling for rotational soil health is the linking of measures of soil physical, chemical and biological properties.

As soils need to be moist, sampling may take place post-cultivation/drilling of winter crops, but leaving a gap of at least one month after soil disturbance. Soil physical properties and numbers of earthworms are recorded in the field at the time of sampling and we are also collecting cores for the measurement of bulk density.

A bulk soil sample is collected to allow extended soil chemical and biological analysis using the NRM Soil Health package plus direct measures of soil organic carbon, total nitrogen, potentially mineralisable nitrogen, microfauna and nematodes. The same soil samples will also be used in the development and validation of DNAbased soil biological indicators. To allow control of the factors under study, many research trials have specific and narrowly focused remits, often with limited acknowledgement of rotational impacts. Consequently, implementation and impact of soil management on farms has been less well studied. The Soil Biology and Soil Health Partnership is deliberately taking another approach and is working with farmer and grower research-innovation groups to evaluate the impacts on soil biology and health across a broad spectrum of crops including field vegetables, climates, soil types and rotations.

For more information on soil biology
and soil health visit:
www.ahdb.org.uk/greatsoils