Defense Compounds Rather Than Nutrient Availability Shape Aggressiveness Trait Variation Along a Leaf Maturity Gradient in a Biotrophic Plant Pathogen

Foliar pathogens face heterogeneous environments depending on the maturity of leaves they interact with. In particular, nutrient availability as well as defense levels may vary significantly, with opposing effects on the success of infection. The present study tested which of these factors have a do...

Full description

Saved in:
Bibliographic Details
Published in:Frontiers in plant science 2018-09, Vol.9, p.1396-1396
Main Authors: Maupetit, Agathe, Larbat, Romain, Pernaci, Michaël, Andrieux, Axelle, Guinet, Cécile, Boutigny, Anne-Laure, Fabre, Bénédicte, Frey, Pascal, Halkett, Fabien
Format: Article
Language:English
Subjects:
aggressiveness traits
constitutive defense
Life Sciences
nutrient availability
Phytopathology and phytopharmacy
Plant Science
plasticity
rust fungus
Vegetal Biology
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Foliar pathogens face heterogeneous environments depending on the maturity of leaves they interact with. In particular, nutrient availability as well as defense levels may vary significantly, with opposing effects on the success of infection. The present study tested which of these factors have a dominant effect on the pathogen's development. Poplar leaf disks of eight maturity levels were inoculated with the poplar rust fungus using an innovative single-spore inoculation procedure. A set of quantitative fungal traits (infection efficiency, latent period, uredinia size, mycelium quantity, sporulation rate, sporulation capacity, and spore volume) was measured on each infected leaf disk. Uninfected parts of the leaves were analyzed for their nutrient (sugars, total C and N) and defense compounds (phenolics) content. We found that is more aggressive on more mature leaves as indicated by wider uredinia and a higher sporulation rate. Other traits varied independently from each other without a consistent pattern. None of the pathogen traits correlated with leaf sugar, total C, or total N content. In contrast, phenolic contents (flavonols, hydroxycinnamic acid esters, and salicinoids) were negatively correlated with uredinia size and sporulation rate. The pathogen's fitness appeared to be more constrained by the constitutive plant defense level than limited by nutrient availability, as evident in the decrease in sporulation.
ISSN:1664-462X
1664-462X
DOI:10.3389/fpls.2018.01396