DEVELOPMENT OF AN EST DATABASE FOR DISCOVERY OF HERBIVORE INDUCED GENES IN Quercus rubra

¹ School of Forest Resources,Pennsylvania State University,University Park, PA 16802

² Department of Entomology,Pennsylvania State University,University Park, PA 16802

Oak species are the dominant angiosperm forest trees across much of the world. However many oaks are in decline due to climate change, disease and insect pests. Insect attacks vary from major epidemics such as the gypsy moth, to sub-lethal but economically important destruction of specific tissues. We have recently started an EST project to study oak response to insect attack. We are sequencing inserts from Quercus rubra (Northern red oak) leaf cDNA libraries prepared from subtracted and reverse-subtracted mRNA of gypsy moth attacked leaves and control tissues. Measurements of concentrations of induced phenolic chemicals and oxidative enzyme activities were also taken on both treated and control seedlings. The sequences of several thousand cDNA inserts will be obtained and putative functions assigned by deduced amino acid sequence homology with known genes. A summary of genes expressed during insect attack will be reported and unique findings on herbivore induced gene expression in oaks will be discussed.