| Titre : | A comparison of light quality and quantity effects on the growth and steady-state and dynamic photosynthetic characteristics of three tropical tree species | | Type de document : | texte imprimé | | Auteurs : | C.T. Ojenguren, Auteur ; R.W. Pearcy, Auteur | | Année de publication : | 1995 | | Importance : | pp. 222-230 | | Présentation : | graph., tabl., réf. | | Note générale : | Extrait de Functional Ecology - Vol.9 - n°2 | | Langues : | Anglais (eng) | | Catégories : | Thésaurus Agrovoc
Photosynthèse ; Croissance ; Lumière ; Forêt ; Dynamique des populations ; Adaptation ; Ombre ; Zone tropicale
| | Résumé : | 1. The role of light quality and quantity on steady-state photosynthetic characteristics, efficiency of lightfleck utilization (LFUE) and growth was evaluated in seedlings of tropical rain-forest trees. 2. The pioneer species, Cecropia obtusifolia and Heliocarpus appendiculatus, and the shade tolerant species, Rheedia edulis, were grown in a greenhouse under contrasting red/far-red (R/FR) ratios characteristic of the open and the shaded forest understorey but with the same low photosynthetically active radiation (PAR). Additionally plants were grown in a high PAR environment with a R/FR characteristic of the open. 3. The pioneer species responded strongly to R/FR in terms of greater height growth and a shift in allocation to stem growth over leaf growth in low R/FR (simulated shade) as compared to high R/FR (open). Light quality, however, had no significant effect on steady-state photosynthetic characteristics or LFUE for any species. 4. Increased light quantity, by contrast, caused photosynthetic acclimation leading to higher photosynthetic capacities. The pioneer species showed a larger capacity for photosynthetic acclimation to light environment than the shade species. LFUE was also affected by light quantity, with the low-light grown plants showing higher LFUE than the high-light grown plants. 5. Results provide evidence that light quality does not play an important role in modulating steady-state and dynamic photosynthetic characteristics during acclimation to shade, even in species that exhibit morphogenetic responses to light quality. | | Type de document : | Tiré à part | | Permalien de la notice : | https://infodoc.agroparistech.fr/index.php?lvl=notice_display&id=148706 |
A comparison of light quality and quantity effects on the growth and steady-state and dynamic photosynthetic characteristics of three tropical tree species [texte imprimé] / C.T. Ojenguren, Auteur ; R.W. Pearcy, Auteur . - 1995 . - pp. 222-230 : graph., tabl., réf. Extrait de Functional Ecology - Vol.9 - n°2 Langues : Anglais ( eng) | Catégories : | Thésaurus Agrovoc
Photosynthèse ; Croissance ; Lumière ; Forêt ; Dynamique des populations ; Adaptation ; Ombre ; Zone tropicale
| | Résumé : | 1. The role of light quality and quantity on steady-state photosynthetic characteristics, efficiency of lightfleck utilization (LFUE) and growth was evaluated in seedlings of tropical rain-forest trees. 2. The pioneer species, Cecropia obtusifolia and Heliocarpus appendiculatus, and the shade tolerant species, Rheedia edulis, were grown in a greenhouse under contrasting red/far-red (R/FR) ratios characteristic of the open and the shaded forest understorey but with the same low photosynthetically active radiation (PAR). Additionally plants were grown in a high PAR environment with a R/FR characteristic of the open. 3. The pioneer species responded strongly to R/FR in terms of greater height growth and a shift in allocation to stem growth over leaf growth in low R/FR (simulated shade) as compared to high R/FR (open). Light quality, however, had no significant effect on steady-state photosynthetic characteristics or LFUE for any species. 4. Increased light quantity, by contrast, caused photosynthetic acclimation leading to higher photosynthetic capacities. The pioneer species showed a larger capacity for photosynthetic acclimation to light environment than the shade species. LFUE was also affected by light quantity, with the low-light grown plants showing higher LFUE than the high-light grown plants. 5. Results provide evidence that light quality does not play an important role in modulating steady-state and dynamic photosynthetic characteristics during acclimation to shade, even in species that exhibit morphogenetic responses to light quality. | | Type de document : | Tiré à part | | Permalien de la notice : | https://infodoc.agroparistech.fr/index.php?lvl=notice_display&id=148706 |
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Ajouter le résultat dans votre panier Faire une suggestion Affiner la recherche Interroger des sources externesUne comparaison des techniques des pépinières en zone tropicale : Australie, Ouganda, Kenya, Vietnam. / Moriz Vohrer (2006)
