The delight of the researcher was palpable. For him, scientific research should be outside the academic environment. “I have been working for more than 20 years on biological methods capable of replacing pesticides. As a first step, basic research serves to increase our knowledge but gaining knowledge is only useful if it helps to improve our society or our living conditions. In the present case, by separating the different molecules of the bouquet of volatile compounds, we were able to identify those that were most responsible for inhibiting the pathogen. What was also interesting was the fact that we were demonstrating a direct effect on the pathogen. The emission of volatile compounds no longer has the simple function of alerting the plant or stimulating its defense mechanisms. Some compounds directly attack the pathogen. Here we are identifying an extra function in the defense mechanisms of plants”. 

From basic research to agriculture, could our study soon be applied to the industry?

At the present time, researchers are in the process of verifying that these two compounds can be used to fight the two destructive diseases. However, the researcher knows that there is a long way to go yet before the science can be practically applied in crop fields. “In this type of case, we must first verify that the compounds identified can be easily reproduced, and in large quantities. The second stage will be to verify that the product is not toxic to plants, humans or the environment. Finally, it is important to test the efficacy of the product in vivo, to verify that the pathogen is indeed inhibited in its natural environment. Once all these stages have been studied, if the product remains interesting, we will patent it and will begin to inform manufacturers”.

The researcher modestly confirms that they are at the stage of testing the toxicity of the product. Research is making steady progress even if the product is not likely to be launched on the market tomorrow. Apart from the safety measures that need to be carried out before the product can be approved, other questions still remain unanswered. Another stage in the process will be to understand how the volatile compounds act on the pathogen, if they affect its membranes or if they penetrate the inside of the fungus to target some of its internal functions. It will also be neccessary to find a way of ensuring that the compound inhibiting the pathogen remains in the area where the pathogen is located, because if the entire product is diffused in a few hours and the plant no longer has any means of defense, the defense shield will not have been effective for long. “It will therefore be neccessary to try to delay the volatility of the compound by an adequate formulation”. 

There are several ways of doing this. The first way is by micro-encapsulation of the volatile compounds. These capsules, when placed on the ground, or planted near the seed, degrade at the required speed and quickly diffuse the inhibiting product. Another solution, as in the case studied here where the origin of the disease is an infection of the seed during germination, is to coat the seed with the volatile products.

All things considered, the recent techniques that have been put in place thanks to phytopathology are encouraging. In the context of the controversial use of toxic pesticides and insecticides, these researchers are coming to the aid of farmers who have been deprived of the tools to fight against the numerous diseases that destroy their harvests. Such a study, concentrating on the systematic use of the inherent weapons plants use to defend themselves, proves that things are heading in the right direction, towards an agricultural sector that is more respectful of the environment while also aiming to increase crop yields. This evolution is happening very quickly.