Chemical-less approach to agriculture have increased yields 5 fold in Namibia and 6 fold in Tanzania
According to reports from the UN's Food and Agriculture Organization, by switching to an ecological approach to agriculture without chemicals, the African countries of Namibia and Tanzania have generated yield increases of five and six fold, respectively (CIS 4).
Source: "Farming Systems that Save and Grow," Factsheet 11, Sustainable Crop Production Intensification, Food and Agriculture Organization, Rome, Italy. http://www.fao.org/ag/save-and-grow/ [verified 4/25/14]