EFFECT OF TEMPERATURE ON NET CARBON DIOXIDE EXCHANGE RATES OF TWELVE BARLEY VARIETIES

Publisher Website
Google Scholar
Abstract
Seedlings of 12 barley varieties were grown in a controlled environment to 21 days of age and then transferred to an apparatus for measuring net carbon dioxide exchange rates. Rates were measured at temperatures ranging from 4 to 34 °C and the results were plotted to provide a response curve for each variety. The response curves were not clearly different between varieties, but some trends were evident. The varieties Husky, Parkland and Vantmore had response curves of similar shape with marked increases with increasing temperature to 14 to 18 °C. Asa, Olli and Pirkka showed a more gradual rise to about 20 °C. Varieties O.A.C. 21, Vantage and Wolfe showed a very rapid increase in carbon dioxide uptake to about 6 °C followed by very little change to 20 °C, leading into a gradual decline. Stavropol, Trebi and White Gatami had maximum rates at a higher temperature. The patterns presented by the varieties may be related to different areas of origin and production. Varieties were markedly different at low temperatures but differed little in response to temperatures near 34 °C. Absolute rates of net carbon dioxide exchange differed markedly among varieties.