Takahashi Fumio, Sato-Nara Kumi, Kobayashi Kazutaka, Suzuki Mitsuo, Suzuki Hitoshi
Photodynamics Research Center, RIKEN, Sendai, Japan.
J Plant Res. 2003 Apr;116(2):83-91. doi: 10.1007/s10265-002-0074-2. Epub 2003 Jan 30.
The effects of sugars on root growth and on development of adventitious roots were analyzed in Arabidopsis thaliana. Seeds were sown on agar plates containing 0.0-5.0% sugars and placed vertically in darkness (DD) or under long day (LD, 16 h:8 h) conditions, so that the seedlings were constantly attached to the agar medium. In the sucrose-supplemented medium, seedlings showed sustained growth in both DD and LD. However, only dark-grown seedlings developed adventitious roots from the elongated hypocotyl. The adventitious roots began to develop 5 days after imbibition and increased in number until day 11. They could, however, be initiated at any position along the hypocotyl, near the cotyledon or the primary root. They were initiated in the pericycle in the same manner as ordinary lateral roots. Sucrose, glucose and fructose greatly stimulated the induction of adventitious roots, but mannose or sorbitol did not. Sucrose at concentrations of 0.5-2.0% was most effective in inducing adventitious roots, although 5.0% sucrose suppressed induction. Direct contact of the hypocotyl with the sugar-supplemented agar medium was indispensable for the induction of adventitious roots.
在拟南芥中分析了糖类对根系生长和不定根发育的影响。将种子播种在含有0.0 - 5.0%糖类的琼脂平板上，并垂直放置在黑暗（DD）或长日照（LD，16小时光照：8小时黑暗）条件下，以使幼苗始终附着在琼脂培养基上。在添加蔗糖的培养基中，幼苗在DD和LD条件下均表现出持续生长。然而，只有在黑暗中生长的幼苗从伸长的下胚轴上长出不定根。不定根在吸胀后5天开始发育，数量在第11天前不断增加。不过，它们可以在下胚轴的任何位置、靠近子叶或主根处起始。它们与普通侧根一样，起源于中柱鞘。蔗糖、葡萄糖和果糖极大地刺激了不定根的诱导，但甘露糖或山梨醇则没有。浓度为0.5 - 2.0%的蔗糖在诱导不定根方面最有效，不过5.0%的蔗糖会抑制诱导。下胚轴与添加糖类的琼脂培养基直接接触对于不定根的诱导是必不可少的。
