Different characteristics of roots in the cadmium-tolerance and Cd-binding complex formation between mono- and dicotyledonous plants
Inouhe, M.; Ninomiya, S.; Tohoyama, H.; Joho, M.; Murayama, T.
Journal of Plant Research 107(1087): 201-207
1994
ISSN/ISBN: 0918-9440 DOI: 10.1007/bf02344245
Accession: 008467626
Effects of Cd-2+ on growth and Cd-binding complex formation in roots were examined with various seedlings of mono- and dicotyledonous plants. Maize, oat, barley and rice exhibited the greater tolerance to Cd-2+ (100 mu-M) than did azuki bean, cucumber, lettuce, pea, radish, sesame and tomato (10-30 mu-M). Azuki bean was the most sensitive to Cd-2+ ( lt 10 mu-M). Under these Cd-treatments, cereal roots accumulated Cd-2+ in the cytoplasmic fractions and transported Cd-2+ into the same fractions of shoot tissues, to larger extents than did dicotyledonous roots. Cereal roots synthesized a Cd-binding complex containing phytochelatins in the cytoplasmic fractions, depending upon Cd-2+ concentrations applied (30-100 mu-M). Such a complex was not detected from the same fractions of dicotyledonous roots treated with Cd-2+. These results suggest that the Cd-binding complex formation has an important role in the tolerance of cereal roots against Cd-2+.