Ecophysiological studies in Hesperaloe funifera (Agavaceae): a potential new CAM crop. Seasonal patterns of photosynthesis

RAVETTA, D.A.; MCLAUGHLIN, S

JOURNAL OF ARID ENVIRONMENTS

ACADEMIC PRESS LTD-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 1996 vol. 33 p. 211 - 223

0140-1963

The objective of this study was to evaluate the effect of seasonal variation intemperature and irradiation on photosynthesis rates, proportion of nocturnalCO2 uptake, and water-use efficiency (WUE) in Hesperaloe funifera (Agavaceae),and to discuss what these seasonal patterns reveal about the nature ofthe interactions among environmental factors as they affect CO2 uptake.CO2 uptake showed the highest 24 h integrated values in fall and springand the lowest in winter and summer. Temperature and light do not appearto interact in a simple multiplicative manner in their relationship tophotosynthesis. A conceptual model describing the seasonal pattern ofphotosynthetic capacity in Hesperaloe is presented.Moderately high daily integrated CO2 uptake rates, a long growing season,and high WUE throughout the year have agronomic significance forHesperaloe as a potential new crop for arid lands.©1996 Academic Press LimitedKeywords: Hesperaloe; Agavaceae; crassulacean acid metabolism; seasonalcarbon fixation; new crops; fiber crops