Biosolution benefits backed by research

• Early use delivers biggest benefits

• Integration with regular agronomy

• Clear health and resilience benefits

Including biosolutions in conventional crop management programmes is helping to boost plant health and resilience.

“There’s clear evidence emerging from our trials that using biosolutions early in a fungicide programme is where they’re likely to deliver the best results,” says Agrii technical manager Jodie Littleford.

Lower disease levels compared to a standard conventional fungicide programme are evident where biosolutions are used earlier in the programme – and integrated with traditional chemistry before disease levels escalate, says Ms Littleford.

“Where this pattern starts to break down is where disease levels have already started to build in the early stages of the spring and the effects of the biosolutions on crop resilience are potentially limited.”

Mode of action

Understanding how to use biosolutions in crop management programmes is key – including a firm grasp of their mode of action.

“Elicitors, for example, trigger the plant’s hypersensitive response. This was discovered in 1992 and is effectively the response the plant has to a pathogen damaging its cell wall and has been associated with disease tolerance.

“Once a hypersensitive response is triggered, it stimulates metabolic pathways in the plant that help with crop resilience and intrinsic defence against these pathogens.”

Peptides, which are specially designed strings of amino acids, have been shown to mimic this cell wall damage and trigger the response, but applying them early in the programme and ahead of disease onset is important, says Ms Littleford.

“In this way, the plant’s immune response has been activated prior to a pathogen attacking.

“It’s the same with fungicides really, where a protective approach is the most effective. If you’re in a situation where you’re having to firefight, then you’re really too late with the application whether it is a conventional fungicide or a biostimulant.

Building blocks

As well as resilience-boosting results with peptides, other biostimulants, including amino acids, PGA (pyroglutamic acid) and phosphite, have all performed well in trials, she says.

“Amino acids are building blocks utilised in a range of biochemical functions including protein synthesis, stress reduction and modulating stomatal opening.

“Biostimulation of these processes can enhance growth, improve nutrient cycling, help crops combat disease and increase productivity.

“PGA and phosphite have also been shown to enhance nutrient use efficiency as well as improving rooting and upregulating photosynthesis, which in turn provides the plant with more energy and resources to thrive.”

Trials carried out in the heightened and sustained disease pressure of the 2024 season have further underlined the known effects of biosolutions in a targeted approach alongside fungicides, says Ms Littleford.

Integrated approach

Trial plots treated with a standard fungicide programme in south Wales had virtually no green leaf area left last summer. Septoria pressure is usually high in south Wales during a normal year – but extreme levels were also seen during this season.

But plots in the same trial with a fully biological approach at T0 and T1 integrating elicitors, amino acids, phosphites and bio-fungicides, had significantly more green leaf area left on the flag leaf.

“So even in a year like the last one, bio-based solutions stacked up against traditional chemistry when used in the right way in a programmed approach.

“Having a fully integrated approach with stronger chemistry when it is needed, particularly on less resistant varieties, can certainly deliver better results in terms of gross margin over input costs.

“But there is also a wide range of options for integrating biosolutions into existing fungicide programmes to protect yields and improve margins, but these do depend on the location and disease pressure seen.”

New technology

One of the most exciting of the newer biostimulant options is Innocul8, containing manganese, zinc and a peptide which has been shown to enhance crops by triggering the plant’s complete hyper-sensitive response, she says.

“At the early assessment timings, where we’ve used Innocul8 at T0 or before, we see enhanced greening and healthier crops carrying lower levels of disease, better able to withstand environmental stress.

“We’ve also seen a consistent yield increase of around a third of a tonne per hectare (0.34t/ha) where we’ve applied Innocul8 at those early timings.

“All the emerging science and trials results are showing biostimulants. Elicitors in particular, to be vital tools in boosting a crop’s ability to withstand the various challenges of climate change and more stressful growing conditions.”