At present, chemical treatments are the main methods for the control of "weeds" with their harmful consequences, including the dispersion of toxic molecules in the environment. The most famous of these treatments is glyphosate. More and more cities or even countries have banned or are planning to ban its use. For example, the cities of Los Angeles (USA) and Laval (Canada) no longer use glyphosate to maintain their green spaces. Malawi and Vietnam have suspended their import of glyphosate while Mexico plans to ban its use in 2024. In France, since 2017, communities of municipalities can no longer use glyphosate and the same applies to private gardeners, since 2019. There are also plans to extend its ban to agricultural uses as soon as a viable alternative is identified. The development of new herbicides is therefore essential to do without glyphosate. The most promising avenue of research at present is the development of bioherbicides, products of natural origin with a weed-killing power that does not cause environmental degradation.
Since 1980, only 13 bioherbicides have been commercialized and currently only 9 are available worldwide. Among these registered bioherbicides, we can mention Collego (based on Colletotrichum gloeosporioides) or Beloukha (based on pelargonic acid). Many new bioherbicides are currently being studied. They are based on the use of microorganisms or on different types of molecules such as mycotoxins (active molecules produced by fungi), terpenes (main constituents of essential oils) or weak acids (citric acid, pelargonic acid...).
Green PRAXIS is currently exploring several avenues of compounds that could be bioherbicides such as allelopathic compounds or amino acids. The former are known to decrease germination and/or plant growth. Amino acids are the main constituents of proteins but can cause metabolic disturbances when they are available in large quantities in the natural environment. These two methods are being tested in the Green PRAXIS laboratory.