Role of gametes and asexual products of algae in the food chain of aquatic medium

Abstract

Experiments conducted by keeping mussel larvae in filtered sea water along with fragments of Viva sp., Chaetomorpha sp. and Cladophora sp. capable of readily releasing gametes in the medium showed that the larvae could metamorphose to settling stage with in 15 to 18 days by actively feeding on the gametes released by these algae. It is also noticed that the breeding cycle of the above algae along with the other algae in the locality coincides with the peak breeding period of mussel in Vizhinjam and in other mussel bed areas. The asexual reproductive products of these algae have also been observed to play in similar role as diet of the larvae and adult mussels. The study shows that gametes and other reprouuctive cells released by algae form a microleval food chain in the aquatic medium enriching the ecosystem. The paper emphasises a new line of investigation to find out the impact of this micro level food chain to improve the fish and shellfish production in coastal brackish water and fresh water ecosystems by comparing the role of other algal groups on a global basis. Eventhough considerahle work has be~n done on a global on the reproduction and propagation of algae, the biologists throughout the world have been concentrating mostly on the biology of reproduction in these groups. However. the role of the gametes and other asexually released products in the aquatic medium other than their natural proc~s of propagation has not been studied. Among a few important works on algae the reviews on the reproduction of algae made by Bold and Wynne(1978) Fritsch (1977) and Bhatia (1975) are worth mentioning and they give a broad picture on the alternation of generations and the reproductive behaviour of the marine,