Seaweed cultivation in India-Present and future

Seaweeds are used as human foods,lock feed and utiliser in different parts of the world. Apart from these traditional uses, the seaweed extractives of red and brown algae such as agar-agar, algin and Carrageenan, are employed in various industries, especially, food, confectionary, pharmaceuticals and textile industries. Recent studies on seaweeds gave promising results on their role in waste treatment and as potential sources of drugs and bio-energy. These new applications will further increase the demand for seaweeds in the near future

Seaweed Resources of India

Seaweeds yield valuable phycocolloids like agar-agar and algin which are widely Bsed in many industries. They are also utilised as food, fodder and fertiliser. Survey of natural seaweed resources and investigation of the chemical composition, methods of extraction, ecology, cultivation and other aspects related to their utilisation are therefore of utmost importance. Majority of the economic seaweeds come under three classes namely the Green algae (Chlorophyceae), the Brown algae (Phaeophyceae) and the Red algae (Rhodophyceae) and they are generally restricted to the relatively narrow littoral and sublittorial belts of the marine environment

Status and future of marine algal research on the East Coast of India

The east coast of India, including the maritime states of West Bengal, Orissa, Andhra Pradesh and part of Tamil Nadu, provides an unique environment for marine communities, since major rivers like Ganges, Mahanadi, Godavari, Krishna and Cauveri, open into Bay of Bengal and highly productive mangrove habitats occur in the river deltas and coral reefs at the southern end. In these marine habitats two types of algae occur- the macro algae or seaweeds and the micro algae or phytoplankton

Seasonal growth and reproduction of Gelidiopsis variabilis (Greville) Schmitz

Seasonal variations in growth, fruiting and sporulation of Gelidiopsis variabilis (Greville) Schmitz occurring on the Visakhapatnam coast have been described. Only tetrasporophytes and vegetative plants were found in the populations analysed for 21/2 yr and seasonal changes were more marked in the abundance of tetrasporophytcs formation of stichidia and in the spore output than in the stature of the plants. Maximum development of the plants was observed each year between October and January-February and peak reproductive activity from July to September

Changes in Mannitol and Alginic Acid Contents of Turbinaria ornata (TURNER) J. AGARDH in Relation to Growth and Fruiting

Biological and chemical studies have been conducted on some important species of Sargassum and Turbinaria to determine the optirnum periods for harvesting the algin-yielding seaweeds o£ the Mandapam area (UMAMAHESWARA RAO, 1969). The present paper reports the results obtained on growth, fruiting in relation to quantitative changes in mannitol and alginic acid contents of Turbinaria ornata (TÜRNER) J. AGARDH for a period of four years, from January 1967 to December 1970. Materials and Method Turbinaria ornata in the Palk Bay, near Mandapam, commonly grows on coral debris and coral stones at l -- 2 m depth. About 50--100 plants were collected from this area at monthly intervals. Total length of all the plants was measured in the laboratory and mean heights of the plants together with their Standard deviations were calculated. Chemical analysis of the dried plants was carried out äs reported earlier (UMAMAHESWARA RAO, 1969

Effect of thermal stress on spore shedding in some red algae of Visakhapatnam coast

Effect of thermal stress on the liberation of tetraspores from Gelidium pusillum (Stackhouse) LeJolis, PterocladiLl heteroplatos (Boergesen) Umamaheswara Rao and Kaliaperurna.l and Gelidiopsis variabilis( Greville) Schmitz was studied. in response to temperatures lower (0° -lOOC)and higher( 40° -45°C)than the tolerance limits of plants. Spore liberation was seen in these algae exposed to low and high temperatures for short durations but the output decreased with increase in the duration of treatment. The temperature tolerance capacity varied in the algae tested

Growth, reproduction and sporulation of marine alga Gelidium pusillum(Stackhouse) Le Jolis

Seasonal aspects of growth. reproduction and spore output in G. pusillum growing (Sept. I 976-Feb. 1979) at Visakhapatnam coast were described. Plants occurred throughout the year with maximum growth in Sept. and Oct. and minimum between Jan. and April. Tetrasporophytes were predominant over the cystocarpic plants and seasonality was not observed in the abundance of these fruiting plants. Under laboratory conditions tetraspore and carpospore shedding was maximum on the 1st d and spore output gradually decreased from 2nd d onwards. Seasonal variations were not observed in the formation of sori and discharge of spores

Effects of environmental factors on the liberation of spores from some red algae of Visakhapatnam coast

Experiments were conducted with tetrasporophytes of Gelidium pusillum (Stackhouse) Le Jolis, Pterocladia heteroplmos (Boergesen) Umamaheswara Rao & Kaliaperumal, and Gelidiopsis variabilis (Greville) Schmitz, to determine the effects of various environmental factors on the liberation of spores. The ability to liberate spores and the quantity of spores shed by these three red algae varied with the different environmental conditions tested. Submerged condition of the plants, long day condition at low illuminance, sea water of 30 to 40/00 salinity and 25 to 30°C temperature were found to be favourable for maximum sheddingofsporcs at Visakhapatnam. The variability observed in spore-shedding under short- and long-day conditions was considered to be due to the photosynthetic effect also noticed in the growth of certain red algae

On two new records of Codiaceae from India

During the course of studies on marine algae growing around Mandapam (79° 8' E., 9° 17' N.) the author collected two green algae of the family Codiaceae; namely Udotea javensis A. & E. S. Gepp and Penicillus sibogae A. & E. S. Gepp. As these two algae have not hitherto been recorded from the Indian coast, their occurrence is reported in this communication

The seaweed potential of the seas around India

The present paper deals with the Indian seaweeds of economic value and the potential resources available in the inshore waters of the country. Results of the sample surveys carried out to estimate the standing crops of all marine plants growing in the Palk Bay area are given. Possibilities of cultivating the commercially valuable species in sheltered and calm areas of the coastline are indicated based on the culture experiments conducted with Gracilaria lichenoides and G. corticat