Category: Organic agriculture

Doyle McKey‘s presentation at IBC18 sounds like a doozy. I was alerted to it by Eve Emshwiller on Twitter, who said, among other things:

McKey: ecological intensification, not just green revolution model “intensification” of ag needed. #ibc18

Music to our ears, of course. Here’s a summary from the (very large) Abstract Book of the congress.

The evolutionary ecology of plant chemical defenses in agroecosystems: past, present and future.

McKey, Gleadow, Cavagnaro

Plant chemical defenses mediate interactions between plants, their herbivores and pathogens, and the naturalenemies of these plant parasites. In domesticated plants, farmers are added to this web of interactions. Plant defenses have been subjected to complex selection pressures under domestication, leading both to decreases and to increases in their concentration, and to shifts in their intra-plant distribution. This complexity is explained partly by variation in the kinds of plants farmers chose to domesticate, and partly by the kinds of environments that nature and farmers combined to create in agroecosystems. Today, the interactions mediated by plant defenses are affected by changing climate, rising temperature and increased atmospheric concentrations of carbon dioxide. These changes can threaten food security by lowering not only the production of food but also its nutritional quality. The strategies proposed to counter these threats envisage a wide range of ways, not mutually exclusive, to manage biotic interactions in agroecosystems. These include modifying crop plants’ natural constitutive and induced defenses and other sources of resistance; engineering crop plants to express novel defenses; and increasing the effectiveness of ‘integrated pest management’ (through natural enemies, other components of agrobiodiversity and pesticides) by modifying the structure and functioning of agroecosystems. In this presentation, we examine these proposed solutions through the evolutionary ecologist’s lens: What are their respective costs and benefits, and how do these affect the ecological situations in which each could help farmers produce sufficient amounts of high-quality food? How can the coevolutionary dynamics of interactions between crop plants and their biotic environment be managed to avert catastrophic fluctuation of yield?