ANAEROBIC INDUCED ETHANOL SYNTHESIS IN THE STEMS OF GREENHOUSE-GROWN CONIFER SEEDLINGS

Ethanol synthesis was induced in stem segments from greenhouse-grown c onifer seedlings by placing them in a N-2 atmosphere at 30 degrees C f or 24 h. Stems from ponderosa pine, Pinus ponderosa Dougl. ex Laws., s ugar pine, Pinus lambertiana Dougl., Pacific silver fir, Abies amabali s Dougl. ex Forbes, and lodgepole pine, Pinus contorta Dougl, ex Loud, produced the highest quantities of ethanol. This group also had the s mallest and slowest growing stems. Within each of these species the am ount of ethanol produced was inversely related to the stem volume. Ste ms from western hemlock, Tsuga heterophylla (Raf.) Sarg., grand fir, A bies grandis Dougl. ex Forbes, Douglas-fir, Pseudotsuga menziesii (Mir b.) France, and western redcedar, Thuja plicata Donn ex D. Don, all pr oduced equivalent but low ethanol concentrations. These species had th e largest and fastest growing stems. In this group only grand fir exhi bited an inverse relationship between ethanol concentrations and stem volume. The relative amounts of ethanol synthesized by stems from Doug las-fir, western hemlock and western redcedar seedlings were not the s ame as subsequently observed in logs from mature trees of the same spe cies under field conditions. Differences in the anaerobic environments for the two stem types could have affected the quantities of ethanol produced. The observed high amounts of ethanol produced by the stems f rom pine species were discussed in terms of their ability to handle pe riods of anaerobic stress or hypoxia.