DEVELOPMENT OF WHEAT (TRITICUM AESTIVUM) POLLEN. II. HISTOCHEMICAL DIFFERENTIATION OF WALL AND UBISCH BODIES DURING DEVELOPMENT

The histochemistry of different developmental stages of the pollen wall, aperture, and Ubisch bodies of Triticum aestivum is examined with light and transmission electron microscopy. Various parts of the callosic envelope of the tetrad spores stain differentially. At the late tetrad stage, the probacules and the coat of pro-Ubisch bodies are densely stained for acidic polysaccharides, protein, and neutral polysaccharides. The protectum and the core of pro-Ubisch bodies are moderately stained. Upon release of microspores from the callosic cell envelope, the stainability for acidic polysaccharides increases in the exine and in the wall of Ubisch bodies, becoming very intense in the wall of mature pollen grains and Ubisch bodies. The stainability for neutral polysaccharides is decreased in the mature pollen wall and in the Ubisch bodies, while the stainability for protein increases. The results also indicate the probability of the presence of unsaturated lipids and the absence of free aldehydes in the pollen wall and Ubisch bodies.