Students in my lab measure benefits of symbiosis to legumes and nitrogen-fixing rhizobia. How much energy can rhizobia divert from nitrogen-fixation to their own reproduction before plants impose sanctions? Would stricter sanctions help future crops in the same soil?
Darwin argued that domesticated species have been "neglected by naturalists." That is still true of agricultural symbionts, such as the rhizobia that provide legume crops with nitrogen. Students in my lab have used rhizobia mainly to test fundamental hypotheses about the evolution of cooperation, with possible practical applications in agriculture. Evolutionary tradeoffs between longevity and reproduction are a significant side-interest, with implications for perennial grain crops and for human longevity.
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Oono, Ryoko, Katherine E. Muller, Randy Ho, Andres Jimenez Salinas, and Robert Ford Denison. 2020. How do less-expensive nitrogen alternatives affect legume sanctions on rhizobia? Ecol Evol 10: 10645-10656
Sadras,V., J. Alston, P. Aphalo, D. Connor, R.F. Denison, et al.. 2020. Making science more effective for agriculture. Advances in Agronomy 163: 153-177
Denison, RF 2019. Evolutionary tradeoffs are key to beneficial manipulation of crops by microbes. American Journal of Botany 106: 1529 -1531
Muller, Katherine E., and R.Ford Denison. 2018. Resource acquisition and allocation traits in symbiotic rhizobia with implications for life-history outside of legume hosts. Royal Society Open Science 5: 181124
Denison, R.Ford 2012. Darwinian Agriculture: How Understanding Evolution Can Improve Agriculture. Princeton University Press, Princeton.
Denison, R.F. 2011. Past evolutionary tradeoffs represent opportunities for crop genetic improvement and increased human lifespan. Evol. Appl. 4: 216-224
Ratcliff, W.C., P. Hawthorne, M. Travisano, and R.F. Denison. 2009. When stress predicts a shrinking gene pool, trading early reproduction for longevity can increase fitness, even with lower fecundity. PLoS One 4: e6055
Kiers, E.T., R.A. Rousseau, S.A. West, and R.F. Denison. 2003. Host sanctions and the legume-rhizobium mutualism. Nature 425: 78-81