3. Co-evolution and adaptation of pathogens and growth and defense of host plants

According to Detlef Weigel, director of the Max Planck Institute for Developmental Biology (Tübingen, Germany), the goal over the coming years will be to understand genomic and geographic patterns in the diversity of immune response.

“We’ve observed that natural variation reveals new aspects of the plant immune system and that, in wild plants, the pathosystems (subsystem defined by the parasite) differ from those of crop and laboratory plants. Also, the tug-of-war between pathogen and host differs if we look at the greenhouse or a field,” he stressed.

The project he has just kicked off will be sequencing the whole genome to describe the genetic diversity of the host plant and two significant pathogens: Pseudomonas and Hyaloperonospora arabidopsidis. The goal is to create an allele map of the host plant resistance and another of the pathogen effectors to show whether local adaptation is more common in the plants or the pathogens.

Another of the numerous work lines open was described by Hailing Jin, professor at the University of California, Riverside (USA): small RNA is a type of short, non-coding RNA involved in silencing the genes of another sequence. “We’ve proven that some small RNA in pathogens can be transferred to the host-plant cells, suppressing the immune system so the infection can successfully take hold. One of these fungal pathogens is Botrytis cinerea, which causes what is known as gray mold in more than one thousand plant species. Plus, we’ve shown that this pathogen may have double chains of RNA and small RNA in its environment. And, applying small RNA to the botrytis genes on the surface of fruits, vegetables or flowers inhibits grey mold,”³ she highlighted. And, in her opinion, this finding opens the door to a new generation of fungicides that are longer-lasting and more eco-friendly.

“For personalized agriculture to become a reality, it is essential for societies to demand that their governments invest more in basic science, which can later be applied. The only limits are those stemming from the funds available to scientists,” explained Ignacio Rubio-Somoza of the University of Barcelona Center for Research in Agricultural Genomics (CRAG) and co-organizer of the event.

Another aspect that must be promoted, in his opinion, is raising general awareness of the fact that scientists “love the earth, nature and the environment more than anyone. And our sole passion is to understand and come up with long-term solutions that are as innocuous as possible. We need to explain ourselves, but the people also have to listen and have the critical thinking and interest in why scientists do what we do. Science education, especially in biology, is key and will stop there from being people who think tomatoes don’t have genes.”