Figure 3.

Embryonic and Vegetative Developmental Defects of 5mARF17 Plants.

(A) Eight-day-old control ARF17 and 5mARF17 T2 seedlings displaying a range of embryonic phenotypes, including lobed cotyledons (bottom left of 5mARF17 panel) and extra cotyledons indicative of trilateral and quadrilateral embryonic symmetry (right 5mARF17 panels).

(B) Scanning electron micrographs of a 6-d-old control ARF17 (left) plant with the normal two cotyledons (asterisks) and two emerging true leaves (arrowheads) and 10-d-old 5mARF17 seedlings (middle and right). The middle plant displays a lobed cotyledon and a downwardly curled cotyledon, and the right plant has three cotyledons (asterisks) and three emerging true leaves (trilateral symmetry).

(C) Scanning electron micrographs of a 10-d-old 5mARF17 seedling (left), 6-d-old 5mARF17 seedling (middle), and magnified view of the 6-d-old 5mARF17 shoot apex (right). Indicative of quadrilaterally symmetric embryos, the 5mARF17 seedlings had four cotyledons (asterisks) and four emerging rosette leaves (arrowheads) rather than two of each.

(D) Scanning electron micrographs of abaxial surfaces of 6-d-old control ARF17 and 5mARF17 cotyledons showing altered epidermal cell shape and organization in the 5mARF17 cotyledon.

(E) Twenty-two-day-old control ARF17 (left) and 5mARF17 (top right) T2 plants and a 30-d-old 5mARF17 T2 plant with severe leaf serration (bottom right).

(F) Rosette leaves from 30-d-old control ARF17 (left) and 5mARF17 (right) T2 plants.

(G) Thirty-two-day-old control ARF17 (left) and 5mARF17 (right) T1 plants. The 5mARF17 plant has bolted.

(H) Magnified view of 5mARF17 plant in (G).

(I) Seventy-two-day-old control ARF17 and three 5mARF17 T2 plants grown in short days (8 h light, 16 h dark). The 5mARF17 developmental defects are increasing in severity from left to right; only the plant with the most severe phenotype has bolted.

(J) Col-0 and 35S:5mARF17 rosette leaves with defects increasing in severity from left to right.