The high productivity of cultivated plants is explained by the physiological traits of their wild parents.

A study by the Rey Juan Carlos University led by Professor Ruben Milla, and in which researchers from the Spanish National Research Council (CSIC) participated, has analyzed why cultivated plants are resource-hogging and fast-growing species. The study, recently published in the journal Nature Plants , analyzes the origin and evolution of different ecophysiological traits of leaves related to water management and carbon fixation capacity. The results of the study help to understand the selection by early farmers of certain wild species for consumption and cultivation .

The researchers used comparative and experimental methods , including collecting published data on thousands of species and conducting a greenhouse experiment, to test the performance of different wild parents of the crop plants and of varieties grown at two stages of domestication: early (traditional old breeds) or late (modern varieties). The work shows that the wild parents of the crops have acquisitive ecophysiological traits oriented towards a very productive but unsparing use of environmental resources, and high rates of gas exchange, i.e. high photosynthesis and stomatal conductance to water vapor, low intrinsic water use efficiency, higher leaf nitrogen concentration, and softer leaves than other wild species that were never domesticated . During domestication and modern improvement, there have been no consistent changes in physiology; ecophysiological traits have increased, decreased, or remained unchanged, idiosyncratically, across species. Furthermore, cultivated plants were found to have less variable ecophysiological traits than wild plants that were never domesticated. The possession of less variable traits and the acquisitive strategy could be due to inheritance from their wild parents, which originally already had a more productive ecophysiology.