Flowering Modification in Trees

The movement of genes from genetically engineered and exotic trees are social, ethical, and ecological problems for society. These problems inhibit acceptance of genetic engineering as a method of tree breeding. We are pursuing a number of different, cutting edge methods to prevent unwanted gene movement. These methods will hopefully enable wider use of genetic engineering to improve tree growth and reduce environmental impacts of forest management. We focus on three genera of trees important to forestry and ornamental horticulture: Populus (poplar, aspen, cottonwood), Eucalyptus, and Liquidambar (sweetgum). We summarized available methods for containment in a recent scientific paper (Vining et al. 2012), and have also published methods for inducing rapid flowering to speed breeding and research (e.g., Klocko et al. 2015). A major effort on RNAi-modified trees based on this grant from USDA resulted in a publication in PLOS One in 2015, a publication in Nature Biotechnology in 2016, and a publication in New Phytologist in 2019. A new focus of the lab is on gene editing of floral genes; our GREAT TREES Coop and a recent major grant from USDA that is summarized here is funding this work. A publication on gene editing efficiency in poplar was published in 2018.