More efficient wheat breeding methods are needed to meet demand for wheat from expected population growth in developing countries. This paper reports results from recent studies conducted at CIMMYT aimed at assessing the use of stomatal aperture-related traits (SATs) as indirect selection criteria for high yield-potential in bread wheat. Two classes of SATs were assessed: the instantaneous trait leaf porosity (POR), which is a close surrogate for stomatal conductance, and the integrative traits ?13C of leaf and grain and ?18O of grain. For 3 out of the 4 populations of breeding lines tested in 2001–02, the results indicated strong prospects for using SATs in screening for high yield potential. Grain ?13C , leaf ?13C and POR each showed promise, with moderate to high heritability, moderate to strong genetic correlations with yield, and yield gains from retrospective selection of about 40–50g m-2 at trial mean yields of 520g m-2 . Grain ?18O showed less promise. Heritability of this trait was moderately high, but grain ?18O was not strongly correlated with yield and retrospective gains from selection were small. For one population, none of the SATs showed any convincing association with yield. The reasons for this need further investigation as SATs are evaluated over additional seasons

Global Wheat Program

English

Lucia Segura

INT1511

CIMMYT Staff Publications Collection