Fig. 2.

The expression of BcMF8 in pollen tubes of the Brassica campestris ssp. chinensis genic male-sterile line system (‘Bcajh97-01A/B’) based on in situ hybridization. (A–D) Longitudinal sections of the pollinated pistils at 1, 3, 10 and 24 HAP hybridized with a BcMF8 antisense probe. A specific hybridization signal (arrowhead) was detected at the stigma at 1 HAP (A). A stronger hybridization signal (arrowhead) was detected at the stigma at 3 HAP and in the growing pollen tubes, which penetrated the style tissue and almost reached the upper end of the transmitting tract of the pistil (asterisk) (B). No hybridization signal was detected in the pollinated pistils at 10 HAP (C) and 24 HAP (D). (E) A section of anther at the binucleate stage hybridized with a BcMF8 antisense probe. Specific hybridization signals were observed in the pollen (arrowhead). (F–I) Longitudinal sections of the unpollinated pistils at 1, 3, 10 and 24 HAP hybridized with a BcMF8 antisense probe. No hybridization signal was detected in the unpollinated pistils. (J) A section of anther at the binucleate stage hybridized with a BcMF8 sense probe as a negative control. (K and L) Magnified images of the corresponding stigma in A and B showing the hybridization signal (arrowhead). (M) Magnified image of the corresponding style in B showing the hybridization signal (arrowhead) in the pollen tubes. Scale bars = 500 µm (A–D, F–I); 100 µm (E, J–M).