Fig. 6.
Transmission electron microscopy of C. bracteata anther on 23 November: outdoor-grown plants (A) and indoor-grown plants (C). (A, B) Anther wall. Note the well-developed anther wall with numerous amyloplasts (arrows) in outdoor-grown plants and the absence of cellular structure in anthers of indoor-grown plants. Scale bar = 2·5 µm. Scanning electron microscopy of pollen grains of outdoor-grown plants (B) and indoor-grown plants (D). Note the squeezed pollen grains of indoor-grown plants. Scale bar = 0·5 µm. Abbreviations: En, endothecium; Ep, epidermis; N, nucleus; M, mitochondria; ML, middle layer; N, nucleus; V, vacuole.