Figure 1. Adaxial outgrowths in Bla-1/Sha hybrids.

(a) Six-week old plants grown at 16°C, long days, of Sha (left), Bla-1/Sha F₁ hybrid (centre) and Bla-1 (right). Arrows indicate de-repressed side shoots in the hybrid. (b) Lesioning is seen in leaves of six-week old F₂ hybrid plants grown at 16°C, long days, where the phenotype segregates (present on left leaf, absent on right leaf). (c) Outgrowths on the petioles of Bla-1/Sha F₂ plants grown at 23°C, long days. (d–f) Transverse sections of Bla-1 (d) and Bla-1/Sha hybrid (e, f). Outgrowths that are caused by proliferation of parenchyma and/or epidermal cells are visible on the adaxial surface of the petiole. Scale bar = 100 µm.