Fig. 5.

Seed maturation transcription factors are required for efficient somatic embryogenesis (SE). (A) Effect of ABI4, ABI5, and ABI3 loss-of-function mutants on 2,4-D-induced SE. The abi3-6 mutant is desiccation intolerant, therefore mature wet seeds were analysed for this mutant, using mature wet Col-0 seeds as a control. (B) Effect of ABI3, ABI4, and ABI5 overexpression on 2,4-D-induced SE. (C–F) Overview of somatic embryo cultures in time for the indicated mutants. The images are light micrographs. The day of culture is indicated above the panels. Statistically significant differences in SE efficiency between wild-type Col-0 and mutant explants were calculated using a two-tailed Student’s t-test (*P<0.05; **P<0.01; ***P<0.001). Error bars represent the SD of three technical replicates. c, cotyledon; r-h, root–hypocotyl region; arrow, somatic embryos; arrowheads, embryogenic tissues; asterisks, callus formed on the petioles or the root–hypocotyl region. Scale bars, 1 mm.