A STUDY ON THE CULTURE OF FREE--LIVING FILAMENTS AND DIRECT SPORE--COLLECTING OF PORPHYRA HAIT ANENSIS

The culturo of free-living filaments for direct sopre-collecting, is an improvedmethod in the cultivation of Porphyra haitanensis Customarily, shells of mollusca suchas Meretrix, oyster etc. had been used for clinging of the filaments. Glass bottles havebeen used to substitute the shells in the new method, carpospores are cultivated in thesea water with sufficient nutrient salts, and then filaments germinate from thecarpospores and grow in suspension in sea water or clinging to the bottle wall. They areready for direct spore--collccting in the Autumn. Results of the experiments are concluded as follow:1. Thallus sclected for carposporc--collecting must be thoroughly cleaned to eliminateall injurious ultachments on it. The most simple and effective way to eliminate injurious algae is to bask the thallus in the sun for 1--2 hrs. and then to rinse it in the disinfectedsea water.2. For the purpose to prolong the growth period of the free--living filaments, thecarpospore-collecting should be taken place before the March.3. The production of the free-living filaments in each 800 ml. bottle is about 2--2. 5g.(wet wt.), under the conditions of sufficeent nutrient salts in the sea water and theintensity of illumination is above 1000 Lux.. By approximate estimation 20 bottlesof filaments are sufficient to meet the need for spore--coll ecting of the area l mu. net.4. In the night, by using running water to promoto the formation of binary branenedcells and the rate of spore-releasing of the filaments is a reliable way to obtainsufficient spores for cultivation5. The suitable date for spore--collecting is at the beginning till middle of Oclober.The optimum time for spore-collecting in a day is 9--11 a. m.