The key to combating vascular wilting in tomatoes, which is caused by a type of Fusarium oxysporum and which is considered this crop's main disease, could be found in a bacteria of the coral reef of the Colombian Caribbean. It could have been found thanks to the research carried out by the bacteriologist Diana Vinchira, master in Sciences-Microbiology and doctor in Biotechnology of the National University of Colombia (UNAL).
The Bioprocessing and Bioprospecting group of the UNAL Institute of Biotechnology (IBUN), in partnership with the company Biocultivos, seeks new sources of nature with industrial potential. In this context, when Dr. Vinchira finished her master's project, she began working with the Chemistry Department's Group of Marine Natural Products and Fruits of Colombia.
This group had just collected microorganisms in the coral reefs of Santa Catalina and Providencia, in the Colombian Caribbean, and wanted to study them to generate some biotechnology-based product.
The bacteriologist was offered to continue the research with this ceparium to find a bio controller against the fungus F. oxysporum f. sp. lycopersici (FOL) among the more than 200 microorganisms in the collection.
"We are carrying out an escalation process with this microorganism to generate a prototype - hand in hand with the Biocultura company - which could be a product that would be used on an industrial scale," the researcher stated.
The next step would be registering it with the Colombian Agricultural Institute (ICA) and validating it in the fields -as it's only been tested in nurseries - and marketing the product in the country.
The researchers' experimentation
First, researchers noticed that the bacterium Paenibacillus sp. alone produced metabolites that are known to inhibit the fungus' growth.
Based on this, they wondered, if that bacterium produced some active metabolites without any stimulus, how would it react to a stimulus? In this case, what the bacterium would do to defend itself if it shared the same space as the pathogenic fungi.
Since putting the bacteria and fungus into real production crops is dangerous, researchers are evaluating other strategies, such as putting it dead in the middle of the culture where the bacteria grows or some metabolite (a molecule that remains of the metabolism) that produces the pathogen in a way that stimulates the production of these antifungal compounds without the need of infecting them with Fusarium.
According to the researcher, the partnership with the Biocultivos company allows them to use their experimental field and, once the product is formulated, they will be able to carry out tests in real conditions. So far, they have only evaluated the plants under controlled conditions and in greenhouses of the UNAL, which, despite not being as controlled as in a laboratory, are still small scaled tests.