Abnormal tapetum during anther development in autotetraploid rice.

<p>(A, B) Giant tapetal cells (A) and prevacuolation of giant tapetal cells (B) during premeiotic interphase. (C-E) Redundant tapetal cells (C) and tapetum degenerating along with the middle layer (D, E) during meiosis. (F, G) Unbalanced tapetum size after meiosis. (H, I) Tapetum cytoplasm that is not deeply stained at the microspore stage. (J, K) Degeneration of the tapetum (J) and abnormal proliferation (K) during the microspore stage. (L) Arrested microspores and larger endothecium in the mature pollen stage. En, ML and Ta indicate the endothecium, middle layer and tapetum, respectively. The red arrow indicates the abnormalities. Bars = 50 μm.