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Biorationals: from glasshouse to field

Developments to extend the uses of biorational products and to discover new active ingredients are constantly sought by Certis Europe

Development of biorationals in rice, here combining biorationals and new ways to apply the products (by drone application)
Trials on Septoria in wheat in Northern France 2021 Untreated crop
Trials on Septoria in wheat in Northern France Biorational at T1
Trials on Septoria in wheat in Northern France Standard T1

by Laurence Antonio Gutiérrez, Marketing and DevReg Manager for Spain & Portugal and Etienne Hinh, Portfolio Development Manager, Arable Crops

(Published in International Pest Control, September/October 2021  Volume 63-5)

Biorationals are defined as “registered plant protection products generally derived from the natural environment, offering improved benefits for plants, people and the planet, which are increasingly important factors for Integrated Crop Production to satisfy requirements of the value chain and consumers.”

Biorational products have now been used extensively in horticulture for many years and developments, both in terms of discovering new active ingredients and of extending the uses of known biorational products to more outdoor crops, are constantly sought by Certis Europe and others in the crop protection industry.

Governments, the value chain and consumers have consistently driven demands over the years for more sustainable and environmentally friendly food production, culminating in the recent European Green Deal, in particular the Farm to Fork and Biodiversity Strategies that aims to encourage new systems of food production and consumption.  Biorationals are also in line with national policies like Ecophyto in France. The planned reductions in the use of pesticides and the aim of increasing organic production will raise enormous challenges for farmers and growers and require huge commitments from the crop protection industry to develop further effective alternative crop protection solutions.

In this context an increasing number of agrochemical products is already being lost, some of which have no real alternative. In the long run this will force the farmer to find new ways of working in open field situations: new crops, crop rotations and cropping systems, mechanised weed control, more resistant varieties, new precision technologies using satellites and digital cameras, robots, etc. for crop protection product application … and last but not least, following the consumer demands and the new EU policies and strategies, the growers would increase the number of  biorational products integrated in their crop programs, providing a complete solution based on integrated pest management including conventional and biorational solutions. 

Substantial progress has been made over the last 20 years in developing Integrated Pest Management programs, including biorational and conventional products, for the control of pests and diseases in a wide variety of crops. Nevertheless, a large proportion of biorational usage remains in the speciality crops sector and much of it under protected conditions. The successful transfer of such products to achieve effective pest control in field crops is a major challenge, not least in terms of application techniques, which are currently not optimised for biorational products in these circumstances. Almost no biorational product proves to have any systemic activity so, to be effective, the product must have contact with its target, even on the underside of leaves and so application quality is key. In addition, biorational products degrade more quickly than conventional synthetic crop protection products and are therefore more susceptible to adverse weather conditions, potentially reducing performance. Work to improve application techniques and characteristics such as rainfastness in biorational products to improve performance is ongoing, but there have already been some promising results. Indeed, several biorational product registrations have already been granted for open field crops and the portfolio is growing.

In the arable sector there are at present still plenty of conventional products available, so farmers are generally not looking to change their current practices dramatically. If they do switch to biorationals they will be looking for performance that equals conventional pesticides in terms of either curative and /or preventative efficacy. At present there are no biorationals offering curative activity. It seems likely that in many cases the introduction of biorationals in open field crops will be rather a matter of changing habits and being part of the new solutions, using combinations of conventional and biorational products, for example in tank mix.

Some segments are identified with more biorational input than others: insecticides, simply on account of the reduced number of new conventional solutions, are high on the list and are used in IPM programs in stone fruit, citrus and vines; fungicides too, where there are many biorational candidates, are registered in wheat, rice, cabbages, tobacco as well as in vines for both table and wine grapes. The herbicide segment seems more likely to remain mainly conventional for longer, due to the availability of new conventional actives from the major companies that meet registration requirements and the lack of biorationals with systemic activity and selectivity. However, biorational molluscicide products and potato sprout suppressants are already widely used.

The search for active ingredients that can compete on price and efficacy with conventional products to protect open field crops and that would be acceptable to farmer practices continues.  The impact of ‘green’ policies may mean that farmers will be more accepting of lower performance from biorational products because they offer other strategic benefits such as resulting in less pollution taxes, for example. We have seen promising trends in the development of biorational cereal fungicide projects, have other biorational products in the registration process and a range of further products for open field use in the development pipeline with field trials underway. There is progress, but it will take time and such products must go through the regulatory process before they can reach the market.