Phenotypic study with counting the number of chromosomes of the female gametophyte of the fern Salvinian natans

Abstract

Plant samples of the sporophyte of Salvinia natans fern, bearing fruiting bodies, were collected from Marsh Al-Hammar, Thi-Qar Governorate, and placed in glass basins filled with water from the collection area. The experiment was conducted in the glass house of the Department / Life Sciences / College of Education / Ibn Al-Haytham / University of Baghdad, starting from October 2008 and the monitoring of the ripening of the fruiting bodies, including the sporophyte they contain, continued until the end of May 2009. It was found that the female gametophyte, the female gametophyte, arises from the growth of the megaspore (1n) in the month of April, as a result of the division of the small spore cell into multiple divisions within the wall of the spore while it is in the megasporangium, creating a mass of cells that rush outside the wall of the case in a green, heart-shaped, cushiony structure. It is the female gametophyte and bears on its abdominal surface a group of Archegonia, the average number of which reached 21, ranging between 19-24 in each female gametophyte. Fertilization occurs in only one archegonia on each plant, around which the gametophyte tissue wraps, forming a floating, misty-shaped structure. Above the surface of the water and attached to the remnants of the wall of the sporangia. The sporophyte then arises from the growth of the fertilized egg. This whole process does not take 15 days. According to the number of chromosomes of the female gametophyte, it reached 9 chromosomes (n = 9).