A rebuilt Bt-Cry3a gene from Mycogen provided virtual immunity to damage from cottonwood leaf beetle under natural infestation in eastern Oregon, and resulted in significantly improved growth. This gene can reduce the need for insecticide use, while improving plantation growth and survival. Using AFLP genetic markers, we created the first genome map of a poplar leaf , beetle, then used it to identify a gene for resistance to Bt. The genome map was composed of 187 segregating loci and 19 linkage groups. This map and its resistance markers may be useful for monitoring resistance development by beetles when transgenic trees are deployed.
Diseases continue to greatly limit plantation productivity.
The genes show the DNA sequence and expression expected for this class of genes. They are prime candidates for use in engineering male and female sterility because of its early and bisexual expression. Sterility would reduce ecological impacts and simplify regulatory approval for transgenic trees. Highly polymorphic DNA markers have been used to quantify gene flow from wild populations and plantations. Ten microsatellite markers were used in paternity analysis to demonstrate high levels of gene movement between wild populations.