UFR-6
Genetic Ancestry
- 50% Poncirus trifoliata
- 50% Mandarin
UFR-6 is a University of Florida citrus rootstock made by somatic hybridization. Its patent describes protoplast fusion of Changsha mandarin embryogenic cells with leaf cells of the 50-7 trifoliate orange selection, producing a tetraploid hybrid.[3]
The UF/IFAS fifth-edition rootstock guide lists first commercial availability in 2015, small tree size, 80–90% seedling uniformity and a good freeze-tolerance rating. The freeze rating is a guide assessment rather than a measured minimum-temperature limit.[2]