Leaf and photosynthetic characteristics of pioneer and forest species in tropical montane habitats |
| |
Authors: | M A Sobrado |
| |
Institution: | (1) Laboratorio de Biología Ambiental de Plantas, Departamento de Biología de Organismos, Universidad Simón Bolívar, Apartado 89.000, Caracas, Venezuela |
| |
Abstract: | Gas exchange and chlorophyll a fluorescence measurements of expanding and adult leaves of four plant species were compared under field conditions. The pioneer
species (PS) tended to have thinner leaves with lower nitrogen content and higher stomatal density compared to forest species
(FS). Expanding leaves featured lower photosynthetic pigment contents and gas exchange capacity than adult leaves consistent
with an immature photosynthetic apparatus. At the time of maximum irradiance, sun-exposed leaves of both PS and FS showed
alteration of initial, variable, and maximum fluorescence as well as their ratios indicating photoinhibition. However, leaves
recovered to some extent at predawn, suggesting the activation of photoprotective mechanisms. Sun-exposed leaves had comparable
responses to high irradiance. |
| |
Keywords: | Additional" target="_blank">Additional Chletra chlorophyll a fluorescence Croton Ficus intercellular CO2 concentration leaf age Oyedea photoinhibition photoprotection stomatal conductance |
本文献已被 SpringerLink 等数据库收录! |
|