There are a range of biological products now coming to market which are being marketed as growth promotion and plant health improvers.
With the regulatory landscape changing and it becoming increasingly difficult to get chemical seed treatments approved, biostimulants are likely to have an increasing role as seed treatments, says Jim Knight.
“Biostimulant seed treatments are the future of seed treatments – the biotechnologies which have been developed are fast providing more tools to growers that can, to some extent, take the place of some of the things we used to do with chemistry.”
One example of the new products on offer is Sylas- ST for use on OSR, a highly concentrated seed treatment that improves the crop’s nutrient and water uptake,
leading to rapid establishment, growth and increased plant biomass, according to UPL.
Trials have shown that as well as improving emergence speed, Sylas-ST also improves a plant’s drought tolerance, due to an increased root structure and increased water uptake, according to Rob Adamson, technical Support for UPL UK and Ireland.
However, care is needed when it comes to choosing a biostimulant seed treatment, says Mr Knight.
“Biostimulant products are reasonably new for the UK market and we have taken some time to understand how to get the best out of them. When you’re dealing with natural plant mechanisms, they are not going to respond in the same way in every scenario, so it’s really important we understand the best place to use them and how to get the best out of them in a farm situation.
“Prosper ST would be one where we’ve learned quite a lot in recent years about what it is actually doing to the plant and where we can use it to the best effect.”
Prosper ST is a phosphite and nutrient blend which works by signalling the plant to search for more available phosphate in the soil, which results in bigger root structures and, therefore, larger plant biomass, says Mr Knight.
“Any seed treatment we can put on which helps with plant rooting is going to be worthwhile because better root structures give better nutrition and moisture, but also help with some of the things that can go wrong in a season, such as waterlogging and drought.”
Another example would be Integral Pro from BASF, a biostimulant seed treatment that also brings some fungicidal activity.
“This is important because we have no other products with fungicidal activity in our OSR seed treatments now, which makes Integral Pro a key part of protecting the seedling from disease, as well as helping the plant to germinate and establish more quickly. Given the challenges, anything that helps OSR out of the ground more quickly is going to have some value,” says Mr Knight.
In cereals, JumpStart WT, which is said to improve phosphate availability, and ProStablish WT, which stimulates mycorrhizae and root development, were introduced to the market by Bayer last year.
The active ingredient in JumpStart WT is a naturally-occurring soil fungus, Penicillium bilaiae, which produces organic compounds that break the bonds between phosphates and cations, so phosphate can be taken up by the plant.
Single-purpose seed dressing, ProStablish WT is co-applied with JumpStart acting as a signal compound to stimulate mycorrhizae fungi to germinate and colonise roots.
By applying the treatments in combination, phosphate becomes more available to be taken up by the roots and making it easier for the crop to access it, which results in both better nutrient and water uptake and a more effective root system, according to Bayer.