Photosynthesis and kinetic characteristics of rubisco in Hibiscus cannabinus L.
Indian J Exp Biol
;
2000 Aug; 38(8): 841-4
Article
Dans Anglais
| IMSEAR
| ID: sea-56897
ABSTRACT
Photosynthetic characteristics in kenaf (Hibiscus cannabinus L.), a C3 plant, were compared with Abelmoschus esculentus (L.) Moench, another member of Malvaceae. Kenaf leaves exhibited significantly higher rate of photosynthesis (40 mg CO2 dm(-2) hr(-1)) which was 24.6 mg dm(-2) hr(-1) in A. esculentus. Rate of photo and dark respiration was similar in both the species. Kenaf leaf photosynthesis had a higher optimum temperature (32 degrees C) than that of A. esculentus (26 degrees C). Photosynthesis in kenaf leaves required higher saturation irradiance (1,600 micromole m(-2) sec(-1)). There was a significant correlation between photosynthetic rate and biomass yield in these species. The primary product of photosynthesis after 5 seconds of 14C-assimilation was 3-PGA in both the species. The kinetic properties of RuBP carboxylase/oxygenase were determined in the leaf extracts. Higher carboxylase activities were recorded with kenaf leaf extracts (245 pmole mg chl(-1) hr(-1)). Km (CO2) for kenaf leaf carboxylase was significantly lower (7.8 microM) than A. esculentus (13.5 microM) and corresponding difference in Vmax values of carboxylase was recorded between the two species. The kinetic characteristics of oxygenase were similar in both the extracts. These results indicated the variation in carboxylase activity and its kinetic characteristics reflected a significant difference in CO2 assimilation in C3 plants.
Texte intégral:
Disponible
Indice:
IMSEAR (Asie du Sud-Est)
Sujet Principal:
Photosynthèse
/
Ribulose bisphosphate carboxylase
/
Cinétique
/
Hibiscus
langue:
Anglais
Texte intégral:
Indian J Exp Biol
Année:
2000
Type:
Article
Documents relatifs à ce sujet
MEDLINE
...
LILACS
LIS