Crop genetic diversity, productivity and stability of agroecosystems. A theoretical and empirical investigation

This paper purports a model of farmers' crop choices in an uncertain environment. The model shows that profit maximizing farmers will choose a crop mix characterised by greater crop diversity if diversity is positively related to productivity and negatively correlated with production and income variability. An application using data from a Vavilov megadiversity spot, southern Italy, from 1970 up to 1993 is provided to test model hypotheses. It is found that interspecies crop genetic diversity is positively related to mean income and negatively related to the variance of income.