Agriculture

Did you know plants can be turned into zombies?

Pumpkins, witches and a spoky castle giving Halloween feeling

When plants are attacked by weird bacteria called Phytoplasma, they undergo extensive changes that scientists describe as making them turn into "zombies". The microscopic parasites hijack plants’ cellular processes to stop their reproduction and keep them in a vegetative "zombie" state. When trees fall under their spell, tangled branches grow close to each other leading to a symptom called “witches' broom”. Phytoplasma parasites are transmitted by insects and can also cause significant damage to grape vines [1], vegetable crops such as carrots and tomatoes as well as cereals such as barley, rice and  maize.

Scientists recently discovered how Phytoplasma control plant development and identified genes that could strengthen plants' immune system [2]. Plant breeding using New Genomic Techniques, such as CRISPR-Cas9, enables scientists to develop news ways to protect crops from zombie making Phytoplasma.  

A plant infected by phytoplamsa bacteria

[1] Phytoplamsa bacteria (Candidatus phytoplasma vitis) are responsible for 'Golden leaf curl', an important disease of vines transmitted by leaf hoppers (insects) in both Italy and France. Where it occurs, insecticide treatments are obligatory by local laws. In France, any case of 'Flavescence dorée' must be also declared to the Plant Protection Services. 

[2] Huang et. al. 2021. Parasitic modulation of host development by ubiquitin-independent protein degradation. Cell  10.1016/j.cell.2021.08.029 & press release: The microbial molecule that turns plants into zombies (jic.ac.uk).