STUDY ON GAMETOPHYTE VEGETATIVE GROWTH OF UNDARIA PINNATIFIDA AND ITS APPLICATIONS

When cultured under certain environmental coriditions (25℃, light intensity 80 μmol/m~2 ·s, LD12/12, in enriched seawater medium with 7 × 10~(-4)mol/L NO_3,-N, 1.56× 10~(-4)mol/L, PO_4-P and supplementsof other elements like Mn, Fe, I, etc.), mate and female gametophytes of U pinnatifida keptgrowing vegetatively and propagated fast at average daily fresh weight increase rate of about 20%. Theempirical formula G_m=G_o. 3~m was established to estimate the output of vegeative gametophytes. Vigorousvegetative gametophyte cells began to form reproductive structures (oogonium and spermatangium, whenthe tmperature was lower than 25℃ and other environmental factors wrre kept optimal. The sufficientsupply of gametophyte cells provided enough seeds for raising Undaria sporelings on prodiction scale.Controlled cross-breeding experiments using selcted male and female gametophyte clones which increasetheir cell number by mitosis instead of meiosis were also carried out in vitro. Juvenile sporophytes fromthe cro

STUDY ON GAMETOPHYTE VEGETATIVE GROWTH OF UNDARIA PINNATIFIDA AND ITS APPLICATIONS