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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

Response of Fv/Fm in S. lycopersicum(A) and S. pimpinellifolium(B) at different days (D) under P16D10, P24D0, and P24D10 growth conditions. The Fv/Fm data were taken at 21:30 CEST. Vertical bars are SEM (n = 3). Treatment means with different letters within each day are significantly different. The statistical analysis was done by the Tukey and Waller–Duncan k-ratio t-test.
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Figure 2: Response of Fv/Fm in S. lycopersicum(A) and S. pimpinellifolium(B) at different days (D) under P16D10, P24D0, and P24D10 growth conditions. The Fv/Fm data were taken at 21:30 CEST. Vertical bars are SEM (n = 3). Treatment means with different letters within each day are significantly different. The statistical analysis was done by the Tukey and Waller–Duncan k-ratio t-test.

Mentions: The Fv/Fm of S. lycopersicum was significantly lower on day 8 and 12 in plants from the CL treatments compared to P16D10 (Figure 2A). The values were lower in P24D0 and intermediate in P24D10. In contrast, there was no significant effect on the Fv/Fm values of S. pimpinellifolium (Figure 2B). The PN of CL-grown plants of S. lycopersicum were similar in the two photoperiods (Table 2). The diurnal variations of PN (between 9:00 and 15:00) in both species were not significantly different at any of the 4 days in P24D0 treatment. In P24D10, the PN at dark period (15:00) was significantly higher than at light period (9:00) on day 3, 6, and 9 for S. lycopersicum, but the diurnal variations were not statistically significant for S. pimpinellifolium (Table 2). In the period corresponding to the dark period, the PN of S. lycopersicum was significantly higher in the P24D10 compared to the P24D0 conditions in two out of 4 days (Table 2). In S. lycopersicum, the PN significantly increased in the P16D10 plants from day 3 to day 12 (P < 0.01), whereas the PN in CL-grown plants were not significantly increased from day 3 to day 12 (P > 0.05). During the light period, the PN of S. pimpinellifolium grown in P24D0 was only significantly reduced in comparison to the P16D10 on day 12 and the PN in all the treatments of this species increased significantly (P < 0.05) during the experiment (Table 2). The daily carbon gain in both species was significantly higher in the CL treatments compared to P16D10 treatment, while it was significantly higher in P24D0 than P24D10 on days 6 and 9 in S. pimpinellifolium (Table 3).


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)

Response of Fv/Fm in S. lycopersicum(A) and S. pimpinellifolium(B) at different days (D) under P16D10, P24D0, and P24D10 growth conditions. The Fv/Fm data were taken at 21:30 CEST. Vertical bars are SEM (n = 3). Treatment means with different letters within each day are significantly different. 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 2: Response of Fv/Fm in S. lycopersicum(A) and S. pimpinellifolium(B) at different days (D) under P16D10, P24D0, and P24D10 growth conditions. The Fv/Fm data were taken at 21:30 CEST. Vertical bars are SEM (n = 3). Treatment means with different letters within each day are significantly different. The statistical analysis was done by the Tukey and Waller–Duncan k-ratio t-test.
Mentions: The Fv/Fm of S. lycopersicum was significantly lower on day 8 and 12 in plants from the CL treatments compared to P16D10 (Figure 2A). The values were lower in P24D0 and intermediate in P24D10. In contrast, there was no significant effect on the Fv/Fm values of S. pimpinellifolium (Figure 2B). The PN of CL-grown plants of S. lycopersicum were similar in the two photoperiods (Table 2). The diurnal variations of PN (between 9:00 and 15:00) in both species were not significantly different at any of the 4 days in P24D0 treatment. In P24D10, the PN at dark period (15:00) was significantly higher than at light period (9:00) on day 3, 6, and 9 for S. lycopersicum, but the diurnal variations were not statistically significant for S. pimpinellifolium (Table 2). In the period corresponding to the dark period, the PN of S. lycopersicum was significantly higher in the P24D10 compared to the P24D0 conditions in two out of 4 days (Table 2). In S. lycopersicum, the PN significantly increased in the P16D10 plants from day 3 to day 12 (P < 0.01), whereas the PN in CL-grown plants were not significantly increased from day 3 to day 12 (P > 0.05). During the light period, the PN of S. pimpinellifolium grown in P24D0 was only significantly reduced in comparison to the P16D10 on day 12 and the PN in all the treatments of this species increased significantly (P < 0.05) during the experiment (Table 2). The daily carbon gain in both species was significantly higher in the CL treatments compared to P16D10 treatment, while it was significantly higher in P24D0 than P24D10 on days 6 and 9 in S. pimpinellifolium (Table 3).

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