Dr. Pilar Maul

Ever wonder why grapefruits do not grow in Alaska? Well, Dr. Pilar Maul, Assistant Professor of Biology, did wonder and with her new research on citrus genes that are cold tolerant we may be a step closer to having fresh grapefruit in the snow.

Her paper, which was recently published in the science journal “Plant, Cell and Environment,” exposes more than 2,000 genes in grapefruit whose job is to tolerate cold temperatures. Dr. Maul co-authored the paper with Gregory T. Mcollum, Mick Popp, Charles L. Guy, and Ron Porat.

“We collected the grapefruits from the trees, removed the peel and extracted their RNA to analyze it,” said Dr. Maul who performed the research at the genomics lab of the United States Department of Agriculture located in Fort Pierce, FL. “We used very modern molecular biology techniques such as DNA arrays and DNA automated sequencers, which allowed us to see the activity of thousands of genes simultaneously, When looking at the large picture, gene interactions are easier to understand.” 

The discovery of thousands of genes in citrus, which may create cold tolerance for the fruits, is a step closer to breedinging lemons, oranges, grapefruits and all kinds of citrus that are tolerant to cold weather. This will not only allow citrus plants to grow in cold weather, but it will also make the exportation of the fruits an easier process while conserving  fruit quality.

“Florida is the largest producer of grapefruit in the world. Most grapefruits that are exported overseas from Florida must follow very stringent quarantine regulations that include storage at low temperatures to kill all fruit flies,” Dr. Maul said. “But, cold temperature storage produces brown patches on the peel that make them unmarketable…if we can make them tolerant to cold, we can ship them anywhere in the world.”