Apple leaf wettability variability as a function of genotype and apple scab susceptibility - INRAE - Institut national de recherche pour l’agriculture, l’alimentation et l’environnement Access content directly
Journal Articles Scientia Horticulturae Year : 2020

Apple leaf wettability variability as a function of genotype and apple scab susceptibility

Abstract

An important group of fungal diseases, such as apple scab on Malus x domestica leaves, perform infection only by remaining wetted by liquid water for a sufficient time, making leaf wetness duration (LWD) a crucial variable in epidemiological risk assessment. LWD is affected by the leaf wettability, i.e. the geometry of a liquid on a leaf as a consequence of the interaction between molecules of water and structural and physicochemical properties of the leaf surface. The variables describing wettability are the contact angles, which result from a genotype's physical and chemical properties. Accordingly, we assumed that wettability could be a direct expression of the genetic resistance of apple genotypes, thus influencing the physicochemical properties of the surface. In order to verify that hypothesis we measured static and dynamic contact angles on seven different Malus x domestica genotypes with various apple scab susceptibilities. The measured contact angle hysteresis was very high (from 58.8° to 82.6° among genotypes), leading to a high variability in possible values of static contact angles of water drops on leaf surface. The results obtained by mimicking both dew like and rain like water depositions during experiments, emphasize the importance of the water deposition process on the static contact angle of a water droplet on a leaf. A positive correlation between dew like droplets and the apple cultivar susceptibility to apple scab was observed and is discussed. This study is valuable for new LWD modeling approaches taking into account the leaf wetting properties.
No file

Dates and versions

hal-02621783 , version 1 (26-05-2020)

Identifiers

Cite

Alexandre Leca, France Rouby, M. Saudreau, André Lacointe. Apple leaf wettability variability as a function of genotype and apple scab susceptibility. Scientia Horticulturae, 2020, 260, 9 p. ⟨10.1016/j.scienta.2019.108890⟩. ⟨hal-02621783⟩
35 View
0 Download

Altmetric

Share

Gmail Mastodon Facebook X LinkedIn More