Plant guttation provides nutrient-rich food for insects
Date
2020Cita bibliográfica
Urbaneja-Bernat, P., Tena, A., González-Cabrera, J., Rodriguez-Saona, C. (2020) Plant guttation provides nutrient-rich food for insects. Proc. R. Soc. B 287: 20201080Abstract
Plant guttation is a fluid from xylem and phloem sap secreted at the margins of
leaves frommany plant species. All previous studies have considered guttation
as awater source for insects. Here,we hypothesized that plant guttation serves
as a reliable and nutrient-rich food source for insects with effects on their communities.
Using highbush blueberries as a study system, we demonstrate that
guttation droplets contain carbohydrates and proteins. Insects fromthree feeding
lifestyles, a herbivore, a parasitic wasp and a predator, increased their
longevity and fecundity when fed on these guttation droplets compared to
those fed on control water. Our results also show that guttation droplets,
unlike nectar, are present on leaves during the entire growing season and are
visited by numerous insects of different orders. In exclusion-field experiments,
the presence of guttation modified the insect community by increasing the
number of predators and parasitic wasps that visited the plants. Overall, our
results demonstrate that plant guttation is highly reliable, compared to other
plant-derived food sources such as nectar, and that it increases the communities
and fitness of insects. Therefore, guttation represents an important plant trait
with profound implications on multi-trophic insect–plant interactions.