Morphology of Marsilea Systematic position Kingdom : Plantae - CEC

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megasporangia are visible as sori. The sori are the reproductive structures arranged in the two alternating rows in the cavity of the sporocarp (Fig. 10). Each sorus has a receptacle which contains one terminal megasporangium and two microsporangia on the lateral sides. It is surrounded by an indusium. The sori overlap each other and the indusia of adjacent sori are partially fused. Fig. 10 Marsilea sp.: A, Vertical transverse section of sporocarp; B, horizontal longitudinal section of sporocarp. The number of sori in a sporocarp varies from two in M. aegyptica to twenty in M. quadrifolia and M. vestita. There are 11 – 12 sori in M. minuta. Each sorus bears both mega and microsporangia. The former are short-stalked and are arranged in a row at the tip of the receptacle, whereas the latter are long- stalked and arise on the sides. The number of micro- and megasporangia varies with species. In M. minuta, a sorus has 4-8 megasporangia and 8-13 microsporangia. Development of sporocarp: Sporocarp originates from one of the marginal cells of a very young leaf, when it is 6-8 cells high. One of the marginal cell cuts off segments on either side and one of the derivatives acts as the apical
cell for the second sporocarp. This process is repeated several times depending on the number of sporocarps formed at the base of a leaf. The sporocarp, initially cuts off segments on either side and forms a mass of undifferentiated cells, which later curves markedly so that its distal end is directed in a horizontal plane. Subsequently, two rows of soral mother cells are differentiated on the ventral side of the young sporocarp. The differential growth of soral mother cells and their derivatives, results in the formation of involutions on the upper surface of the sorus. These involutions grow into arc- shaped depressions called soral canals. The soral mother cells divide to form receptacular surface in the alternating rows. The sporangial initial develops on the receptacular surface in acropetal succession, i.e. first sporangial initial is formed at the apex of receptacle and it forms megasporangia. Subsequently, two initials are formed on the lateral sides of the receptacle. They functions as microsporangial initial, each forming a microsporangium (Fig. 11).
Page 1 and 2: Morphology of Marsilea Marsilea, co
Page 3 and 4: Root: The primary root formed on th
Page 5 and 6: Anatomy of Marsilea Rhizome (Stem)
Page 7 and 8: Leaflet Fig. 5 Marsilea:Transverse
Page 9 and 10: Vascular bundle lies within the end
Page 11: Fig. 8 Marsilea: different modes of
Page 15 and 16: its development. The outer cell of
Page 17 and 18: gametophyte, while prothallial cell
Page 19: produced within the fruit body, the

Morphology of Marsilea Systematic position Kingdom : Plantae - CEC

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