Carbon dioxide blocks the stigma callose response following incompatible pollinations in <i>Brassica</i>

Abstract

Abstract. Carbon dioxide is known to overcome sporophytic self‐incompatibility in Brassica. Elevated CO 2 (30 mmol CO 2 mol ‐1 air), supplied via a flowthrough gas system, was shown to block the formation of rejection callose in the surface stigmatic papillae of Brassica campestris var. T15 following self‐pollination. Possible mechanisms by which CO 2 may affect callose formation are discussed.