Two sides of a leaf blade : Blumeria graminis needs chemical cues in cuticular waxes of Lolium perenne for germination and differentiation

Plant surface characteristics were repeatedly shown to play a pivotal role in plant-pathogen interactions. The abaxial leaf surface of perennial ryegrass (Lolium perenne) is extremely glossy and wettable compared to the glaucous and more hydrophobic adaxial surface. Earlier investigations have demonstrated that the abaxial leaf surface was rarely infected by powdery mildew (Blumeria graminis), even when the adaxial surface was densely colonized. This led to the assumption that components of the abaxial epicuticular leaf wax might contribute to the observed impairment of growth and development of B. graminis conidia on abaxial surfaces of L. perenne. To re-assess this hypothesis, we analyzed abundance and chemical composition of L. perenne ab- and adaxial epicuticular wax fractions. While the adaxial epicuticular waxes were dominated by primary alcohols and esters, the abaxial fraction was mainly composed of n-alkanes and aldehydes. However, the major germination and differentiation inducing compound, the C26-aldehyde n-hexacosanal, was not present in the abaxial epicuticular waxes. Spiking of isolated abaxial epicuticular Lolium waxes with synthetically produced n-hexacosanal allowed reconstituting germination and differentiation rates of B. graminis in an in vitro germination assay using wax-coated glass slides. Hence, the absence of the C26-aldehyde from the abaxial surface in combination with a distinctly reduced surface hydrophobicity appears to be primarily responsible for the failure of normal germling development of B. graminis on the abaxial leaf surfaces of L. perenne.

Medienart:

E-Artikel

Erscheinungsjahr:

2009

Erschienen:

2009

Enthalten in:

Zur Gesamtaufnahme - volume:230

Enthalten in:

Planta - 230(2009), 1 vom: 08. Juni, Seite 95-105

Sprache:

Englisch

Beteiligte Personen:

Ringelmann, Anna [VerfasserIn]
Riedel, Michael [VerfasserIn]
Riederer, Markus [VerfasserIn]
Hildebrandt, Ulrich [VerfasserIn]

Links:

Volltext

Themen:

1-hexacosanol
Fatty Alcohols
Journal Article
M7SD300NNB
Research Support, Non-U.S. Gov't
Waxes

Anmerkungen:

Date Completed 02.11.2009

Date Revised 20.10.2021

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1007/s00425-009-0924-4

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM187703299