Lindcove REC: Developing citrus varieties resistant to huanglongbing disease

Abstract

News from the RECs Lindcove REC: Developing citrus varieties resistant to huanglongbing disease O f the many citrus varieties trialed at the Lindcove Research and Extension Center (REC), one has been a source of more than $14 million in licensing revenue to UC since 2006: the seedless, easy peel Tango mandarin, bred by Mikeal Roose, professor of genetics in the Department of Botany and Plant Sciences at UC Riverside, and UC Riverside researcher Tim Williams. Many millions of Tango trees have been planted worldwide, 4 million or so in California alone. Mikeal Roose, professor of genetics at UC Riverside, whose program bred the seedless Tango mandarin, which has been a huge commercial success. Now he’s working on a solution to the citrus industry’s greatest challenge — huanglongbing (HLB) disease. Elizabeth Grafton-Cardwell Eremocitrus crosses at Lindcove REC are potentially promising in the pursuit of a genetic source of resistance to HLB. The fruit is golfball size and inedible. 18 CALIFORNIA AGRICULTURE • VOLUME 71, NUMBER 1 Lonnie Duka Three trees with inedible fruit at Lindcove REC, on the eastern edge of the San Joaquin Valley near Visalia, have Roose’s attention now. They are 34-year-old trees, crosses of sweet orange (two) and Rangpur lime (one) with Eremocitrus glauca, the desert lime, a wild Australian citrus relative, which he had forgotten about until recently. It’s a long shot, but they could lead to an even bigger winner than Tango has been — a citrus variety resistant to huanglongbing (HLB) disease, the greatest threat to California’s citrus industry.