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Continuous light increases growth, daily carbon gain, antioxidants, and alters carbohydrate metabolism in a cultivated and a wild tomato species.

Haque MS, Kjaer KH, Rosenqvist E, Ottosen CO - Front Plant Sci (2015)

Bottom Line: The results demonstrated that CL conditions mainly affected the photosynthetic apparatus of a cultivated species (S. lycopersicum), and to a less degree to the wild species (S. pimpinellifolium).The negative effects of the CL could be alleviated by diurnal temperature variations, but the physiological mechanisms behind these are less clear.The results also show that the genetic potential for reducing the negative effects of CL does exist in the tomato germplasm.

View Article: PubMed Central - PubMed

Affiliation: Department of Food Science, Aarhus University Aarslev, Denmark.

ABSTRACT
Cultivated tomato species develop leaf injury while grown in continuous light (CL). Growth, photosynthesis, carbohydrate metabolism and antioxidative enzyme activities of a cultivated (Solanum lycopersicum L. 'Aromata') and a wild tomato species (Solanum pimpinellifolium L.) were compared in this study aiming to analyze the species-specific differences and thermoperiod effects in responses to CL. The species were subjected to three photoperiodic treatments for 12 days in climate chambers: 16-h photoperiod with a light/dark temperature of 26/16°C (P16D10 or control); CL with a constant temperature of 23°C (P24D0); CL with a variable temperature of 26/16°C (P24D10). The results showed that both species grown in CL had higher dry matter production due to the continuous photosynthesis and a subsequent increase in carbon gain. In S. lycopersicum, the rate of photosynthesis and the maximum photochemical efficiency of photosystem II declined in CL with the development of leaf chlorosis, reduction in the leaf chlorophyll content and a higher activity of antioxidative enzymes. The normal diurnal patterns of starch and sugar were only present under control conditions. The results demonstrated that CL conditions mainly affected the photosynthetic apparatus of a cultivated species (S. lycopersicum), and to a less degree to the wild species (S. pimpinellifolium). The negative effects of the CL could be alleviated by diurnal temperature variations, but the physiological mechanisms behind these are less clear. The results also show that the genetic potential for reducing the negative effects of CL does exist in the tomato germplasm.

No MeSH data available.


Related in: MedlinePlus

Catalase (CAT, A), Ascorbate peroxidase (APX, B), and Superoxide dismutase (SOD, C) enzymes activities in the plants of S. lycopersicum and S. pimpinellifolium at different days in P16D10, P24D0, and P24D10 growth conditions. The data were taken at the end of the light period on day 12 (12:30 CEST). Vertical bars are SEM (n = 4). Treatment means with different letters within each species are significantly different and the statistical analysis was done by the Tukey and Waller–Duncan k-ratio t-test.
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Figure 5: Catalase (CAT, A), Ascorbate peroxidase (APX, B), and Superoxide dismutase (SOD, C) enzymes activities in the plants of S. lycopersicum and S. pimpinellifolium at different days in P16D10, P24D0, and P24D10 growth conditions. The data were taken at the end of the light period on day 12 (12:30 CEST). Vertical bars are SEM (n = 4). Treatment means with different letters within each species are significantly different and the statistical analysis was done by the Tukey and Waller–Duncan k-ratio t-test.

Mentions: The activities of antioxidative enzymes in leaves are shown for the end of light period. At the end of the light period on day 12, the activity of CAT were significantly higher in S. lycopersicum grown in P24D0 compared to P24D10 and P16D10, whereas no significant difference in CAT activity were seen in S. pimpinellifolium (Figure 5A). The APX activities in both species did not differ significantly (Figure 5B). In S. lycopersicum, the SOD activities were significantly higher in P24D0 and P24D10 conditions in comparison to the SOD activity in P16D10 plants, while no significant differences in SOD activities was seen in S. pimpinellifolium (Figure 5C).


Continuous light increases growth, daily carbon gain, antioxidants, and alters carbohydrate metabolism in a cultivated and a wild tomato species.

Haque MS, Kjaer KH, Rosenqvist E, Ottosen CO - Front Plant Sci (2015)

Catalase (CAT, A), Ascorbate peroxidase (APX, B), and Superoxide dismutase (SOD, C) enzymes activities in the plants of S. lycopersicum and S. pimpinellifolium at different days in P16D10, P24D0, and P24D10 growth conditions. The data were taken at the end of the light period on day 12 (12:30 CEST). Vertical bars are SEM (n = 4). Treatment means with different letters within each species are significantly different and the statistical analysis was done by the Tukey and Waller–Duncan k-ratio t-test.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4499675&req=5

Figure 5: Catalase (CAT, A), Ascorbate peroxidase (APX, B), and Superoxide dismutase (SOD, C) enzymes activities in the plants of S. lycopersicum and S. pimpinellifolium at different days in P16D10, P24D0, and P24D10 growth conditions. The data were taken at the end of the light period on day 12 (12:30 CEST). Vertical bars are SEM (n = 4). Treatment means with different letters within each species are significantly different and the statistical analysis was done by the Tukey and Waller–Duncan k-ratio t-test.
Mentions: The activities of antioxidative enzymes in leaves are shown for the end of light period. At the end of the light period on day 12, the activity of CAT were significantly higher in S. lycopersicum grown in P24D0 compared to P24D10 and P16D10, whereas no significant difference in CAT activity were seen in S. pimpinellifolium (Figure 5A). The APX activities in both species did not differ significantly (Figure 5B). In S. lycopersicum, the SOD activities were significantly higher in P24D0 and P24D10 conditions in comparison to the SOD activity in P16D10 plants, while no significant differences in SOD activities was seen in S. pimpinellifolium (Figure 5C).

Bottom Line: The results demonstrated that CL conditions mainly affected the photosynthetic apparatus of a cultivated species (S. lycopersicum), and to a less degree to the wild species (S. pimpinellifolium).The negative effects of the CL could be alleviated by diurnal temperature variations, but the physiological mechanisms behind these are less clear.The results also show that the genetic potential for reducing the negative effects of CL does exist in the tomato germplasm.

View Article: PubMed Central - PubMed

Affiliation: Department of Food Science, Aarhus University Aarslev, Denmark.

ABSTRACT
Cultivated tomato species develop leaf injury while grown in continuous light (CL). Growth, photosynthesis, carbohydrate metabolism and antioxidative enzyme activities of a cultivated (Solanum lycopersicum L. 'Aromata') and a wild tomato species (Solanum pimpinellifolium L.) were compared in this study aiming to analyze the species-specific differences and thermoperiod effects in responses to CL. The species were subjected to three photoperiodic treatments for 12 days in climate chambers: 16-h photoperiod with a light/dark temperature of 26/16°C (P16D10 or control); CL with a constant temperature of 23°C (P24D0); CL with a variable temperature of 26/16°C (P24D10). The results showed that both species grown in CL had higher dry matter production due to the continuous photosynthesis and a subsequent increase in carbon gain. In S. lycopersicum, the rate of photosynthesis and the maximum photochemical efficiency of photosystem II declined in CL with the development of leaf chlorosis, reduction in the leaf chlorophyll content and a higher activity of antioxidative enzymes. The normal diurnal patterns of starch and sugar were only present under control conditions. The results demonstrated that CL conditions mainly affected the photosynthetic apparatus of a cultivated species (S. lycopersicum), and to a less degree to the wild species (S. pimpinellifolium). The negative effects of the CL could be alleviated by diurnal temperature variations, but the physiological mechanisms behind these are less clear. The results also show that the genetic potential for reducing the negative effects of CL does exist in the tomato germplasm.

No MeSH data available.


Related in: MedlinePlus