‘KinnowLS’ will not arrive in U.S. produce aisles for at least five years.

“It generally takes about that long to propagate citrus trees,” Roose said. Citrus is grown by ‘budding,’ not by planting a seed. This is because trees grown from a citrus seed are often quite different from the mother tree and the trees may be fruitless for many years. To circumvent these problems, growers and researchers grow seedlings from citrus seeds and then tightly splice onto their rootstock seedling a small amount of material, called a bud, from a tree of the desired variety.
When a new variety is released, citrus nurseries get a few buds from which they make “mother” trees. Buds from these trees make many “increase” trees, and then buds from the increase trees are used to make the trees sold to growers.

“These cycles take time,” Roose said. “After the grower plants trees, they do not have much fruit until the third year after planting.”

Mutation breeding is a technique commonly used by plant scientists to produce useful and desired traits in crops – e.g., larger seeds, new colors, or sweeter fruits – that either cannot be found in nature or have been lost during evolution. The mutations – changes in the structure of genes – are artificially induced by treatment with certain physical or chemical agents. In nature, spontaneous mutations, which are mutations that occur naturally, occasionally take place; mutation breeding can speed this up.

Currently, UCR has 12 ‘KinnowLS’ trees. Six other locations in California each have a dozen ‘KinnowLS’ trees also.

The development of ‘KinnowLS’ was funded by the California Citrus Research Board, the California Citrus Nursery Board and the UCR Agricultural Experiment Station.

For information about licensing ‘KinnowLS,’ contact Joyce Patrona at UCR's Office of Technology Commercialization, Office of Research.