5, Chapter 5 External links Effects of pollination on Citrus plants Pollination of Citrus by Honey Bees Citrus Research and Education Center of IFAS (largest citrus research center in world) Citrus Variety Collection by the University of California Citrus (Mark Rieger, Professor of Horticulture, University of Georgia) Fundecitrus Fund for Citrus Plant Protection is an organization of citrus Brazilian producers and processors.