Материал из Антэкология /// Anthecology
Pollen Bud Formation and its Role in Ophiorrhiza spp.
The anther in Ophiorrhiza is dithecous and tetralocular, its development being of the dicotyledonous type. The anther wall comprises epidermis, endothecium, middle layer and secretory tapetum. The pollen grains are tricolpate and triporate. The microspore nucleus undergoes division to form a vegetative nucleus and a generative nucleus and protrusions (pollen buds) are formed from the germ pores after the first division of the microspore nucleus. The vegetative nucleus moves into one of these buds or first breaks into a number of irregularly sized nuclear particles which enter into one, two or into all three buds, where they degenerate. Then the pollen buds are separated and the generative nucleus divides inside the pollen tube to form two sperms.