The impact of biostimulants on vegetable crops: between promise and reality

A fast-growing market with recently introduced regulations

This talk, presented by CTIFL at SIVAL 2025, highlighted the boom in biostimulants for vegetable crops. The biostimulants market has been growing rapidly since the 2010s, with European regulations coming into force in 2022. These regulations have enabled biostimulants to be better defined as substances or micro-organisms that have a direct effect on plant nutritional processes, independently of nutrient inputs. In addition, precise requirements in terms of safety and agronomic efficacy are now required for their marketing.

Biostimulants fall into three main categories: probiotics, which contain live micro-organisms that stimulate plant growth; prebiotics, which promote microbial activity in the soil; and postbiotics, derived from microbial metabolism. However, analyses of solutions available on the market show a wide disparity in composition and efficacy, calling into question the reliability of certain formulations.

Test results and agronomic issues

Trials carried out as part of the RECCABLE project focused on five representative crops: tomatoes, cucumbers, lettuces, spinach and radishes. The aim was to evaluate the efficacy of biostimulants under different environmental stresses - hydric, cold thermal and hot thermal - and to analyze their effects on yield, quality and shelf life.

The results revealed that the effect of biostimulants varies according to the target crop and the type of stress encountered. For example, some products, such as fermented nettle extract, had positive effects on lettuce in comfortable conditions, while others, such as certain algae, proved ineffective or even counter-productive. Overall, out of 145 combinations tested, only 24 gave positive results, illustrating the need for a detailed approach adapted to the species and environmental conditions.

Prospects and limits for production applications

While encouraging results were obtained under controlled conditions, field application proved more complex. No significant improvement in the productivity or quality of the vegetables analyzed was observed in the real-life environment. One of the major lessons of the study is that biostimulants must be carefully integrated into an overall technical itinerary, combined with practices such as organic fertilization or reduced tillage.

Trials on soilless crops, notably cucumbers, also confirm that in optimized production contexts - regulated temperature, controlled water supply and inert substrate - the effect of biostimulants remains limited. On the other hand, the biogenerator, which relies on the biomagnification of indigenous micro-organisms, has shown a real impact on root development and crop health, suggesting a more promising avenue to explore.

Speakers

Charlotte BERTHELOT - Head of the Sustainability of Vegetable Production Systems Unit - CTIFL

SYLVAIN GERARD - Plant health advisor - CDDM

ARJUNA RAVINDIRANE - Greenhouse vegetable crop protection advisor - CDDM

PIERRE PARODI - Greenhouse cucumber production advisor - CDDM

Landry ROSSDEUTSCH - DSPA Unit Manager - CTIFL