Inequality of global crop diversity changes from 1961 to 2020

Abstract Crop diversity is vital for stability of food supply and sustainable agriculture, but limited understanding of its variability and driving mechanisms hampers effective management. Using data from 211 countries and over 60 years (1961-2020), here we show that global overall crop diversity increases while decline is found in one-third countries, and species evenness index decreases in half of global countries during the study period. Farm size, multiple cropping index, farmers’ income, and irrigation emerge as key drivers to elucidate inter-country variations. Farm size is the primary contributor, reducing approximately 5% of the global crop diversity from 1961 to 2020. Future scenarios project a 9% decline in crop diversity by 2050, while this decline trend would be reversed to increase 3-5% with lower inequalities among countries through better agricultural management. This is essential to increase the stability of agriculture for multiple UN sustainable development goals including hunger, poverty, and inequality.