When it comes to growing staple crops like wheat, maize or potatoes, there are a plethora of fungicides to choose from. However, for crops that are not widely grown, there can be few, or even no fungicides available. Why would this be? Especially as some of these crops can yield extremely high profits for farmers. It all comes down to the fact that while the value is high to the farmer, there just aren’t that many hectares grown to make them interesting to multinational agrochemical companies. The multinational agrochemical companies cannot justify the very high costs of developing and registering fungicides for use on crops that will not give good return on investments. This issue has been one of the main reasons why niche crops have failed to develop beyond a few enthusiastic growers over the years. I have visited farmers of niche crops like borage where the farmer has had to stand and watch as pests and disease destroy their crops in bad years.
However, when the European Union introduced their ‘Basic Substance’ regulations in 2016, this situation changed. Chitosan was registered for use as a bio-fungicide and the registration listed the crops where it could be used in the broadest terms possible. So unlike conventional fungicides, where a registration would need to list every crop type (chicory, cabbage, onions etc), the registration for chitosan just reads ’vegetables’, and ‘fruits’. This means that chitosan can be used as a bio-fungicide on every vegetable crop, every fruit crop, and every crop grown for use in animal feed.
For some crops, this makes chitosan the only realistic option for use as a fungicide! This includes;
Hemp, Wasabi, Samphire, Artichoke, Sweet Potato, rhubarb, Watercress, Medlar, and Borage.
For other crops, there is only one registered fungicide (Asparagus, Basil, Celery, Chives, Sage, Coriander, Rosemary, Fennel), or two fungicides (chicory) available to the grower. Even then, the one that is allowed is usually either mandipropamid, which is highly toxic to the environment, or azoxystrobin, which is acutely toxic if inhaled by the user, and toxic to the environment.
Even Linseed (flax), which while not on the scale of wheat and barley, is still a broad-acre arable crop, has only 3 registered fungicides that can be used on it.
This contrasts with the situation in wheat, where there are lots of different registered active ingredients available to farmers that can be found in over 400 different fungicides! The same is true of other staple crops, like potato, where there are over 200 registered fungicides on the UK database.
We at Eutrema would love to turn this missed opportunity into a golden one for chitosan in niche crops. We are very keen to talk to fruit and vegetable farmers about helping them trial this and other new pest and disease opportunities. So, if you are growing a niche crop and struggling with a plant health issue, please get in touch and we can set up a trial with full technical support and arrange a site visit. We can even provide samples of products for testing.
All data taken from the Health and Safety Executive’s Pesticide Database https://secure.pesticides.gov.uk/pestreg/prodsearch.asp
Note: the list above does not cover ‘biological’ fungicides that are based on living microorganisms. There are only a few of these registered in the UK at present, but they can be used on all edible crops. While biological fungicides are a good option for some growers, their efficacy is often debatable and they can be hit or miss with farmers.