Pollen tube length in parents and F1 progeny. (A), (B) and (C) show average pollen tube length of parents and F1s generated from reciprocal crosses. Comparisons between Col, C24 and their F1 progeny are shown in (A); comparisons between Ws, C24 and their F1 progeny are shown in (B); comparisons between Col, An and their F1 progeny are shown in (C). ANOVA and multiple comparisons with LSD were performed. Error bars are SEM. Letters indicate significant differences at P<0.5. Values followed by the same letter are not significantly different.