Ulva lactuca Linnaeus


Ulva lactuca Linnaeus


Plant attached, foliaceous, bright green to lightgreen, fading to yellowish and sometimes darker when young; thallus consists of large expanded sheet two cells in thickness and frequently several meters in length; the thallus remains attached to the substratum by a holdfast composed of rhizoidal outgrowth from the lower cells, the stalk inconspicuous or apparently absent; blade lanceolate to rounded, often somewhat lobed and undulate or folded, to 6 dm long or more, and relatively broad; margin of thallus ruffled and wavy and folded; thallus lobes varying in thickness, 40 - 45µ at margins, midportion 60 - 65 µ; one cell layer thick; cells in cross section subquadrate with rounded corners; in surface view closely packed, 13 - 15 µ in diameter; cross section of the thallus shows that the cells are isodiametric or vertically elongated to the thallus surface; cell walls are more or less confluent with one another to form a tough gelatinous matrix; cells usually about as tall as broad in section, each cell possesed a single cup shaped chloroplast which lies next to the outer face of the cell; each chloroplast contains one pyrenoid; cells are uninucleate, nucleus is variously located in the interior half of the cell; cell division takes place anywhere in a thallus, cell division take place in a plane perpendicular to the thallus surface; the lower portion of the thallus certain cells send out long colourless rhizoids which grow between the two layers of cells and intertwine freely with one another;. the rhizoids emerge from thallus near the point of attachment to the substratum and become closely intermingled to one another forming a pseudoparenchymatous holdfast

Distribution : Gujarat, Maharashtra, Goa, Karnataka, Kerala, Lakshadweep.

Ecological status : Open coast (intertidal ), Estuaries and mangroves

IUCN status : LR

Uses : Food, animal feed, medicine

Culture/Cultivation : None