海带雄配子体单性生殖叶状体的特性

Properties of Monogenetic Thalli From Male Gametophytes of Laminaria japonica Aresch

海带雄配子体经单个分离培养，长成丝状体细胞，这些细胞体积逐渐增大，由单性生殖直接发育成叶状体。这种叶状体的畸形率达９３．３％，将叶状体养殖在海上，能长成大海带，但它们都不能成熟。这些叶状体在同－克隆遗传特性十分一致，不同克隆则存在明显差异。

The individual male gametophytes of Laminaria japonica under culture condition of isolation could grow into multicellular branching filaments. Monogenesis takes place in the cells of those swelling filaments and leads to thalli afterwards. Young monogenetic thalli have been observed to have very high abnormal rate, about 93.7%. Chromosome sets of monogenetic thalli are all haploid. When cultured in the sea, monogenetic thalli can grow into large blades, but meiosis hasn't been observed. These thalli cannot mature to form sporange, so there is no spore. Thalli from male gametophytes of the same clone extremely resemble each other in genetic properties, but rather different between thalli from different clones. Researchers believe that after artificially induced doubling of chromosomes, monogenetic thalli ought to have reproductive capacity, and their spores will develop into male gametophytes.