Role of chromosome 3A in stomatal resistance of winter wheat

Leaf stomatal resistance, through transpiration and photosynthesis control, constitutes a major factor of productivity and adaptation in wheat. The aim of the investigations reported here was to identify chromosomal effects on the expression of the maximum stomatal resistance, determined under optimum conditions of irradiance and water supply. Leaf stomatal resistance was measured, on wheat grown in pots under natural and well-watered conditions, using a LI-COR LI-6200 portable photosynthesis system under a saturating light>1400 μmol m-1 s-2. Reciprocal sets of chromosome substitution lines between two hard red winter wheat cultivars, Wichita and Cheyenne, were used to identify the chromosomes involved in the expression of this trait. The two parental cultivars were significantly different for the parameter investigated. Chromosome 3A appeared to be involved in the expression of the stomatal resistance value under optimum conditions. Taking into account the relationships previously established between this parameter and some agronomic traits, chromosome 3A might be involved directly in productivity-determining processes or in the adaptation to water conditions, in wheat.