Diurnal and seasonal changes in Prunus amygdalus gas exchanges

28Citations
Citations of this article
10Readers
Mendeley users who have this article in their library.

Abstract

Diurnal courses in net photosynthetic rate (P(N)), stomatal conductance (g(s)), leaf water potential (ψ), internal CO2 concentration (c(i)), and water use efficiency (WUE) were studied as season progressed, in relation to environmental factors in field grown Prunus amygdalus. In sun leaves P(N) reached maximum between 09:00 to 11:00 h and subsequently declined when high temperature and low humidity occurred. An increase was observed late in the afternoon. A decrease in g(s) and ψ was found as season progressed in both years of measurements. In periods of high evaporative demand, ψ was very low, however, it did not explain the reductions Of P(N) in all the three periods (spring, early and late summer). Midday depression of P(N) and g(s) seemed to be related with leaf temperature (T(l)) and high irradiance. Increase in c(i) and F0 and decrease in F(v)/F(m) found between 12:00 and 14:00 h corresponded to the decrease in P(N). Therefore, a transient modification of photosynthetic machinery might be considered. WUE was negatively correlated with vapour pressure difference of leaf to air, that decreased during the day. The September values, higher than in the previous months, were due to the lower seasonal decreases in P(N) than in g(s).

Cite

CITATION STYLE

APA

Matos, M. C., Matos, A. A., Mantas, A., Cordeiro, V., & Vieira Da Silva, J. B. (1998). Diurnal and seasonal changes in Prunus amygdalus gas exchanges. Photosynthetica, 35(4), 517–524. https://doi.org/10.1023/A:1006922822385

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free