Development of Male and Female Gametophytes in Cannabis sativa L. cv. Helena (Cannabaceae)

This study investigated key aspects of the reproductive potential of C. sativa cv. Helena. It focused on the development of male and female gametophytes, embryos, and endosperm formation. The developmental stages of pollen grains, embryo sacs, and their formation were revealed. The anther and development of the male gametophyte were as follows: tetrasporangiate anther, (whose wall is developed by the Dicotyledonous type and consists of the epidermis, fibrous endothecium, two middle layers, and glandular tapetum) and two-celled mature pollen. The ovule and development of the female gametophyte were characterized by an upper unilocular ovary containing two anatropous, crassinucellate, bitegmic ovules. The female gametophyte follows the Polygonum (monosporic) type. The development also includes nuclear endosperm formation and the presence of an embryo sac haustorium. A high pollen and seed viability was estimated. This fact, combined with the normal running of the processes of formation and development of the female gametophyte, embryo-, and endospermogenesis provide high reproductive potential for the studied cultivar of C. sativa. These findings contribute to a better understanding of C. sativa reproductive biology and provide valuable insights for breeding programs aimed at optimizing cultivar selection.