The influence of light environment on photosynthesis and basal methylbutenol emission from Pinus ponderosa |
| |
| Authors: | DENNIS W GRAY ALLEN H GOLDSTEIN & MANUEL T LERDAU |
| |
| Institution: | Department of Ecology and Evolutionary Biology, University of Connecticut, 75 North Eagleville Road, Storrs, CT 06269–3043, USA,;Department of Environmental Science, Policy and Management (ESPM), University of California at Berkeley, 151 Hilgard Hall, Berkeley, CA 94720, USA and;Department of Ecology and Evolution, State University of New York, Stony Brook, NY 11794–5245, USA |
| |
| Abstract: | Methylbutenol is a 5-carbon alcohol that is produced and emitted by several species of pine in western North America, and may have important impacts on the tropospheric chemistry of this region. In the present study the response of methylbutenol basal emission rate (measured at a constant light intensity of 1500 µmol m−2 s−1 and temperature of 30 °C) to the light and temperature conditions of the growth environment was examined, using field-grown plants shielded with shade cloth of various densities. Methylbutenol basal emission rates increased linearly with the temperature of the growth environment but did not respond to the shading of foliage during growth and development. Both photosynthesis and basal methylbutenol emission rate declined in older needles; however, these declines appear to result from parallel but independent processes and not from basal MBO emission rate directly tracking photosynthetic rates. Older needles did not occupy cooler microenvironments within the canopy; and thus differing thermal microenvironment could not explain the reduced MBO emission in older needles. |
| |
| Keywords: | light methylbutenol needle age photosynthesis ponderosa pine shade temperature volatile organic compounds (VOCs) |
|
|
