Assessment of Pollen Viability and Germination Through Histochemical, In Vivo and In Vitro Methods

Pollen viability is a key parameter for understanding the functioning of plant reproductive systems and for supporting strategies aimed at genetic resource conservation and plant breeding. Accurate assessments of this attribute are essential for identifying genotypes with a higher reproductive rate, monitoring prezygotic barriers, testing compatibility between individuals, and planning controlled crosses, especially in cases of floral asynchrony or spatial isolation. Accordingly, this chapter compiles the main methods used for this purpose, providing detailed and up-to-date protocols. It covers histochemical tests using different stains (TTC, FDA, modified Alexander stain, and acetocarmine), in vitro pollen germination assays using specific culture media (BK, BM, RM, and PEG), and in vivo analysis of pollen tube growth through fluorescence microscopy with aniline blue staining, as well as viability tests based on fruit and seed set. Each methodology is presented with corresponding materials, procedures, and explanatory notes. The techniques described are broadly applicable and can be adapted to a wide range of plant species and research objectives.