A Novel Tool for Genetic Transformation in Trees
Genetic manipulation of trees is difficult. Using the universal vector IL-60 derived from Tomato Yellow Leaf Curl Virus (TYLCV) and auxiliary constructs, we introduced and expressed genes in grapevine, and orange trees. The genes were expressed in the trees after the constructs were introduced by direct injection into the phloem, root uptake or grafting, or in cuttings from intact plants that had been expressing the introduced genes for years. Moreover, because the disarmed virus does not support rolling-circle replication, viral progeny single-stranded DNA is not produced, IL-60 is not integrated into the plant's genome, and the construct, including the expressed gene, is not heritable. Moreover, IL-60 is not transmitted by natural insect vectors of TYLCV . The introduction of these constructs into trees, seeds and cuttings or grafts provides an easy, inexpensive and rapid way of introducing genes into trees and vegetatively propagated plants such as grapevine.