Recently, researchers from the Max Planck Institute for Chemical Ecology conducted a study on a species of wild tobacco - Nicotiana attenuata. They found that there are some mutant strains with weaker defense abilities against insect attacks in the natural populations of Nicotiana attenuata. Although these mutant strains are more vulnerable to pest infestation, they grow faster.

 

By establishing a "MAGIC" population that captures a large portion of the genetic diversity of the whole Nicotiana attenuata species and constructing a high-quality reference genome, the researchers succeeded in locating key gene variations that influence defense signaling transduction and accumulation of jasmonic acid conjugates in these mutant strains. A mutation in one key gene JAR that affects defense-related signaling transduction causes these strains to prioritize growth and reproduction over enhancing defense.

 

The results show that this mutation has been maintained in the population for at least 10 years. Robust genetic networks can buffer the decline in defense caused by the mutation, enabling these mutant strains to survive in nature. In years with low pest pressure, the strategy of prioritizing growth and reproduction provides an advantage for these mutant strains. The study highlights the importance of maintaining genetic diversity in populations.