The Effects of Powdery Mildew (Blumeria Graminis F. Sp. Hordei) Infection on Stomatal Resistance in Cultivated and Wild Barley Lines

Abdellah  Akhkha

Biology Department, Taibah University, Madinah Munawwarah, Kingdom of Saudi Arabia.

ABSTRACT: The objective of these experiments was to examine how stomatal resistance changed in infected leaves of Powdery Mildew (Blumeria graminis) tolerant and non-tolerant barley lines compared to uninfected leaves in both light and dark, and to determine how much changes in stomatal behaviour following infection could be involved in the reductions in photosynthesis and consequently in reduced dry matter production reported in Akhkha et al. (2003a, 2003b). It was found that infection by powdery mildew increased stomatal resistance in the light in all three lines indicating that mildew induced stomatal closure and consequently limiting CO2 diffusion to the carboxylation sites and causing a decline in the rates of photosynthesis. In contrast, stomata failed to close completely in the dark in all three lines.

KEYWORDS: Powdery Mildew; (Blumeria graminis); stomatal resistance; wild barley lines

[ HTML Full Text]