Plant iron acquisition strategy exploited by an insect herbivore ($) (Science)

When it comes to evading pests and pathogens, stealth comes in handy. Anything that advertises “food here” is an invitation. Therefore, the work of Hu et al. shouldn’t be surprising, but it is a great story. Phytosiderophores such as benzoxazinoid are secreted by roots to chelate iron and facilitate its uptake. Hu et al. found that the benzoxazinoid/ iron complex attracts the western corn rootworm (WCR) herbivore of maize to maize roots. Furthermore, the herbivore benefits from iron assimilated via the benzoxazinoid/iron complex, and a breakdown compound derived from benzoxazinoid confers protection for the herbivore against a pathogenic nematode pest. As the authors observe, “The diverse costs and benefits of the benzoxazinoid pathway for maize represent an optimization problem for plant breeding that may have contributed to the persistence of WCR as a damaging maize pest.” (Summary by Mary Williams) Science 10.1126/science.aat4082