Fig. 3. Mutations in Arabidopsis HEC genes result in reduced fertility. (A) Wild-type Col-0 fruit; arrowhead points to shadow cast by developing seed. (B) hec1 fruit show no obvious abnormal phenotype. (C) hec3 fruit are shorter and exhibit reduced fertility; arrowhead points to empty space that should be occupied by seed. (D) hec1 hec3 fruit are variable in size but generally short, with significantly reduced fertility. (E) HEC3p:HEC3 rescues hec1 hec3. (F) HEC2-RNAi hec1 hec3 fruit are completely sterile. (G-J) Pollen tubes stained with Aniline Blue 24 hours post-pollination. In the wild type (G) and hec1 (H), the bulk of the pollen tubes have nearly reached the base of the ovary (arrowhead). In hec3 (I), pollen tubes are fewer in number and have not penetrated as far as in the wild type or hec1 (arrowhead). In hec1 hec3 (J) there is a significant reduction in pollen tubes entering the ovary, and penetration along the apical-basal axis is greatly diminished (arrowhead). Scale bars: 1 mm in A-F; 0.1 mm in G-J.