Figure 2

Cross-sections of anthers from wild-type (WT) and PGMS mutant (MT) cotton ( Gossypium hirsutum L.) at different developmental stages. Cross-sections of WT and MT anthers at the (A, G) meiotic stage (MC), (B, H) TTP stage, (C, I) early UNP stage, (D, J) late UNP stage, (E, K) BNP stage and (F, L) flowering stage are shown. The red arrows (C, I) indicate the degraded tapetum in the WT and the entire tapetum in the MT. The white arrows (D, J) indicate the residual tapetum in the WT and condensed tapetum in the MT. Bars = 50 μm in (A) to (D) and (G) to (J), and 100 μm in E, F, K and L. E, epidermis; En, endothecium; Mc, mother cells T, tapetum; Tds, tetrads; Ms, microspore; DT, degraded tapetum; ET, entire tapetum; RT, residual tapetum; CT, condensed tapetum; Pg, pollen grain; DA, dehisced anther; and InA, indehisced anther.