Ovule and pollen development in Camelina sativa provides systematic insights

Plant sexual reproduction involves highly structured and specialized organs: stamens (male) and gynoecium (female, containing ovules). These organs synchronously develop within protective flower buds. Investigating ovules and pollen is crucial for understanding aspects of fertility and sterility in plants. Research on their development and embryogenesis plays a significant role in determining the taxonomic relationships of various species. Paraffin-embedding associated to examination with light microscope showed the development of ovules and pollen grains in Camelina sativa, a key oilseed crop. The findings indicated that the anthers exhibit tetrasporangiate characteristics, with the anther wall consisting of the epidermis, mechanical layer, transitional layer, and tapetum. The microsporogenesis type is simultaneous and microspore tetrads arrange in tetrahedral tetrads. Scanning electron microscope observations showed that mature pollen grains have a tricolporate aperture and are medium-sized, with microreticulate exine ornamentation on the pollen wall. The gynoecium is characterized as bicarpellate, and the ovule in its mature state is classified as amphitropous and bitegmic. The meiosis division of megasporocytes yields a linear tetrad formation. The eight-nucleate embryo sac following the Polygonum type pattern. With a broader systematic perspective, these embryological and palynological features demonstrate evolutionary conservatism within the Brassicaceae, with minor distinctions potentially representing adaptive changes.