Intimate Alliances: Plants and their Microsymbionts

Summary (With Ulrike Mathesius) - This lecture describes two very intimate symbiotic mutualisms: one is that which occurs between bacteria (rhizobia or Frankia) and their plant hosts resulting in the production of nitrogen-fixing nodules. The other is the interaction between two different types of mycorrhizal fungi and their plant hosts resulting in enhanced nutrient uptake. Successful formation of these mutualistic symbioses is a complex process that requires signaling and recognition, morphological and physiological responses, and biochemical contributions from both the plant and microsymbiont. Collectively these intimate alliances play a major role in nutrient assimilation by plants, and by extension, to humans and other animals.