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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

Chl a, Chl b and Chl a/b ratio of S. lycopersicum(A,C,E) and S. pimpinellifolium(B,D,F) at different days under P16D10, P24D0, and P24D10 growth conditions. The pigment data was taken at the end of the light period (EL, 12:30 CEST) of each day. Vertical bars are SEM (n = 4). Treatment means with different letters within each day are significantly different and the statistical analysis was done by the Tukey and Waller–Duncan k-ratio t-test.
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Figure 3: Chl a, Chl b and Chl a/b ratio of S. lycopersicum(A,C,E) and S. pimpinellifolium(B,D,F) at different days under P16D10, P24D0, and P24D10 growth conditions. The pigment data was taken at the end of the light period (EL, 12:30 CEST) of each day. Vertical bars are SEM (n = 4). Treatment means with different letters within each day are significantly different and the statistical analysis was done by the Tukey and Waller–Duncan k-ratio t-test.

Mentions: There was no significant effect of CL on the leaf Chl a content in any of the species on day 5. After 12 days, the leaf Chl a content was significantly reduced in both species in P24D0. In S. lycopersicum leaf Chl a significantly increased in P24D10, while was unaffected in S. pimpinellifolium (Figures 3A,B). In contrast, the Chl b content in S. lycopersicum leaves was significantly higher in P24D10 than in P24D0 and P16D10 on day 5, whereas on day 12, CL-grown plants had significantly lower leaf Chl b contents than the P16D10 plants (Figure 3C). In S. pimpinellifolium, the leaf Chl b content was significantly lower in P24D0 than in the P16D10 and P24D10 on both days (Figure 3D). The leaf Chl a/b ratio was significantly higher in CL-grown plants of both species after 12 days (Figures 3E,F). The leaf Chl a/b ratio in P24D0 grown plants was higher in S. pimpinellifolium than in S. lycopersicum (Figures 3E,F).


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)

Chl a, Chl b and Chl a/b ratio of S. lycopersicum(A,C,E) and S. pimpinellifolium(B,D,F) at different days under P16D10, P24D0, and P24D10 growth conditions. The pigment data was taken at the end of the light period (EL, 12:30 CEST) of each day. Vertical bars are SEM (n = 4). Treatment means with different letters within each day 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 3: Chl a, Chl b and Chl a/b ratio of S. lycopersicum(A,C,E) and S. pimpinellifolium(B,D,F) at different days under P16D10, P24D0, and P24D10 growth conditions. The pigment data was taken at the end of the light period (EL, 12:30 CEST) of each day. Vertical bars are SEM (n = 4). Treatment means with different letters within each day are significantly different and the statistical analysis was done by the Tukey and Waller–Duncan k-ratio t-test.
Mentions: There was no significant effect of CL on the leaf Chl a content in any of the species on day 5. After 12 days, the leaf Chl a content was significantly reduced in both species in P24D0. In S. lycopersicum leaf Chl a significantly increased in P24D10, while was unaffected in S. pimpinellifolium (Figures 3A,B). In contrast, the Chl b content in S. lycopersicum leaves was significantly higher in P24D10 than in P24D0 and P16D10 on day 5, whereas on day 12, CL-grown plants had significantly lower leaf Chl b contents than the P16D10 plants (Figure 3C). In S. pimpinellifolium, the leaf Chl b content was significantly lower in P24D0 than in the P16D10 and P24D10 on both days (Figure 3D). The leaf Chl a/b ratio was significantly higher in CL-grown plants of both species after 12 days (Figures 3E,F). The leaf Chl a/b ratio in P24D0 grown plants was higher in S. pimpinellifolium than in S. lycopersicum (Figures 3E,F).

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