The propagation of Irish moss in tanks. Comparative growth at different locations. 1974

The growth of Chondrus crispus plants in tanks of fertilized and unfertilized seawater at Sandy Cove, Halifax Co., and Meteghan, Digby Co., Nova Scotia and Pointe Sapin, New Brunswick was compared during June to August 1974. The selected strain of Chondus crispus, T4, grew more rapidly and produced more carrageenan than locally harvested plants. The effect of low nitrogen availability during periods of rapid growth on production was observed only at Halifax (T4) and Meteghan (local plants) whereas in 1973 this effect (Neish effect) was observed at all four test locations. A weight loss occurred when locally harvested plants were grown in unfertilized sea water at Pointe Sapin. The relative number of tetrasporic plants also decreased.NRC publication: Ye

The propagation of Irish moss in tanks. Comparative growth at different locations. 1973

Chrondus crispus was grown vegetatively in seawater in outdoor tanks at four different locations in the Maritimes. The growth rate and production of carrageenan by strain T4 (a carposporic plant) was superior to that obtained from wild plants (a mixture of carposporic and tetrasporic plants) obtained from the area adjacent to the trials. The results obtained at the two locations in Nova Scotia were similar. The slightly higher yields of plants in Ellerslie, P.E.I. could be attributed to the more favorable growth conditions, including nutrients and temperature. More carrageenan was produced per tank by the unfertilized plants than by the fertilized plants.On a cultiv\ue9 du Chondrus crispus de facon v\ue9g\ue9tative dans des basins d'eau de mer, \ue0 quatre endoits diff\ue9rents dans les Maritimes. La souche T4 (algue \ue0 carpospores) avait un taux de croissance plus \ue9lev\ue9 et produisait plus de carragah\ue9nine que les esp\ue8ces sauvages (m\ue9lange d'algues \ue0 carpospores et t\ue9traspores) croissant dans la r\ue9gion adjacente \ue0 celle des essais. Les r\ue9sultats provenant des deux r\ue9gions situ\ue9es en Nouvelle-Ecosse \ue9taient semblables. Des conditions de croissance plus favorable (richesse en nutriments, temp\ue9rature et salinit\ue9 plus propices), peuvent expliquer les productions l\ue9g\ue8rement plus \ue9lev\ue9es des esp\ue8ces cultiv\ue9es \ue0 Ellerslie (I.-P.-\uc9.). Les algues non f\ue9cond\ue9es ont produit par bassin plus de carragah\ue9nine que les algues f\ue9cond\ue9es.NRC publication: Ye

Vegetative propagation of Chrondrus crispus (Irish moss) in tanks

Chondrus crispus (Irish moss) can be propagated vegetatively in flowing seawater in tanks. Experiments have been conducted in small and medium sized tanks in the greenhouse to determine some of the conditions required for successful vegetative propagation. The factors tested included light, temperature, density, and nutrition. The plants used in these tests were a clone of a single plant (T4) selected on the basis on rapid growth and relative freedom from epiphytes. The use of a single clone reduces problems arising from genetic variability. The paper describes further experiments done with this clone (T4) on a somewhat larger scale, and in outdoor tanks to confirm previous results.NRC publication: Ye

Further experiments (1972) on the vegetative propagation of Chondrus crispus T4

Experiments were conducted on Chondrus crispus, strain T4, to provide further information on conditions needed to obtain increased carrageenan yields from culture tanks. At low densities (0.15 lb per ft2), high N-content plants grown without fertillizer increased their dry matter and carrageenan content more rapidly than at higher densities. An initial density of 0.6 lb per ft2 produced the largest amount of carrageenan over a one month period. Green plexiglass filters placed over tanks inhibited the growth of green epiphytes but also reduced the growth of the Chondrus. Growth rate was greater under continuous illumination than under normal light-dark photoperiod. The rates at which plants grew in fertillized or unfertillized seawater decreased at temperatures above 21\ub0C.NRC publication: Ye