Researchers from the University of Salamanca have discovered a biological method for inherited two-fold improvement of tomato plants which allows them to reach up to 30 percent more growth and provides them with effective protection against pathogens in successive generations.
A study carried out by researchers of the Hispano-Portuguese Institute for Agricultural Reseach(CIALE) in Salamanca reveals the growth potential of tomato plants induced by interaction with the fungus Trichoderma atroviride, which is transmitted to the next generations in addition to immunizing them from the nematode Meloidogyne javanica, one of their main pathogens and often a cause of important economic losses. This will mean a significant improvement in the yield of future harvests.
The The Phytopathology and Biological Control Group comprising Hugo Agripino de Medeiros, María Belén Rubio, Rosa Hermosa and Enrique Monte is working on a project to improve tomato crops using as a disease control agent the fungus Trichoderma atroviride, which is also known to improve up to 30% the growth of the plant on which it acts. Previous studies have indicated that having the fungus intervene on the roots of the plant can help it develop strong growth under normal conditions – without external pathogens or stressors, such as lack of water, higher soil salinity or excessive cold or heat. Similarly, T. atroviride is an effective remedy against the nematode Meloidogyne javanica, the main enemy of tomato crops that gets into the tissues of the root, forming infective galls that eventually kill the plant. The presence of Trichoderma in the root induces in the plant the production of defense-related phytohormones, such as salicylic acid, jasmonic acid and ethylene, achieving a 42% reduction in the number of galls generated by this small worm, 60% less eggs deposited and a decrease of up to 90% of adult individuals who finally manage to colonize it. A third improvement due to the presence of the fungus in the plant is the better resistance it has to the external stressors mentioned above.
Until now it was thought that Trichoderma could act only in one way or the other: if it combated the nematode it did not promote growth and vice versa, if it boosted growth, it could not fight the pathogens. This is because either of these actions entails such a high energy expenditure for the plant that it has to economize its use, either for improvement or defense strategies.
However, the experiment led by Enrique Monte and published in the prestigious Scientific Reports of the Nature group shows that a plant treated with T. atroviride produces seeds that give rise to a next generation of plants that are bigger and at the same time more resistant to pathogens like M. javanica, and thus we obtain a doubly improved plant in a natural way.
Juan M. Corchado 