Treatment of isolated pistils with protease inhibitors overcomes the self-incompatibility response in buckwheat.

Abstract

Isolated pistils of distylous buckwheat (Fagopyrum esculentum Moench) were treated with protease inhibitors (PMSF, pepstatin A, and antipain). Pistils were cross- or self- pollinated, and growth of pollen tubes was observed under a fluorescence microscope. Treatments with all inhibitors suppressed inhibition of self-pollen tube growth, suggesting that activity of proteases is involved in rejection of self-pollen during the SI response.