Fig. 2. Anther and pollen development in wild type and duet. Plastic cross-sections of anthers. (A,D,G) Wild type; (B,C,E,F,H,I) duet. (A,B) Anthers with pollen mother cells at stage 5, all the layers of the anther are present in both genotypes. (C) duet microspore mother cell at meiosis; pollen mother cells (PMCs) surrounded by a layer of callose. (D) Stage 7 anther showing tetrads held together by a layer of callose. (E) duet anther with dyads, triads, tetrads: products of a defective meiosis. (F) Products of aberrant meiosis separate out, enlarge and undergo nuclear division (arrowheads). (G) Stage 12 anther containing mature pollen. (H) Enlarged microspore-like cells (arrowheads) with a single nucleus and lacking exine. (I) Late stage anther showing empty locules. CL, callose layer; E, epidermis; En, endothecium; Ml, middle layer; PMC, pollen mother cell; T, tapetum; Tds, tetrads. Scale bars: 25 µm (A,B,C,F,G,I) and 12.5 µm (D,H,E).