SEM observation the pollen-stigma interaction in self-incompatible strains of brassica campestris

Brassica campestris의 自家不和合性 系統에 있어서 花粉-柱頭 相互作用에 關한 SEM 觀察

The behavior of pollen and stigma was compared between self(incompatible)-and cross(compatible)-pollinations in connection with self-incompatibility in Brassica campestris L. through scanning electron microscope(SEM). Whithin 30 min after pollination, swollen pollen grains began to emerge a large quantity of secretion from one of the three furrows. The secretion covered the papilla cells and pollen altogether in the form of a film for about two hrs. The swelling was quicker and secretion was more abundant in the cross-pollination as compared with the self-pollinations. Recognition reaction between self and non-self occurs during the phase, but the discrimination doses not give conclusive effects. As the result of the recognition reaction, self-pollen tubes are unable to penetrate the papilla cell walls. Thus, the recognition reaction occurs at two phases ; pollen hydration-germination and pollen tube penetration. Although the self pollen tubes cannot penetrate papilla cells, the contact between a pollen papilla without breakage. This suggests that they were not separated from papilla without breakage. This suggests that a metabolic interaction has occurred between pollen tubes and papilla cells. On the other hand, the self pollen tubes elongated on the surface of papilla cells during night, indicating that they have a potential to elongate after the contact.