Unformatted text preview: plants. The Rhizobium bacteria that form root nodules in legumes are the best known nitrogen-fixing associates. Such bacteria can convert atmospheric nitrogen into ammonia, the first in a series of bacterial reactions that provides soluble nitrate ions for plant use. Each legume has a host-specific . Chemical signals (flavenoids) from legume roots stimulate to activate a set of bacterial Nod (nodule) genes that produce enzymes that affect root hair growth and formation of the plasma membrane infection thread as a means for the to invade the root cortex cells. Once within the cortex cells, Nod factors promote dedifferentiation and cell division to initiate the nodule formation. root nodules Nodule, xs...
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- Fall '09
- Rhizobium, Rhizobium root nodules