Influence of N and K fertilization and growth temperature on C/C ratios of timothy (Phleum pratense L.).

Measurements have been reported of carbon isotope ratios of timothy grown at different temperatures and with varying nitrogen and potassium supplies. Both total plant tissue and extracted plant tissue have been analyzed. The C/C ratios were found to vary both with temperature and with nutrient level; the highest values of δC were found under the most optimum growth conditions.