New Insight on Low-K Lettuce: From Photosynthesis to Primary and Secondary Metabolites
With the increase in dialysis patients worldwide, the demand for low-K vegetables is growing. Thus, a type of lettuce with a low-K content has been marketed in Japan. To learn more about low-K vegetables, information is needed on the physiological differences between these vegetables and those with...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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American Society for Horticultural Science (ASHS)
2021-04-01
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| Series: | HortScience |
| Subjects: | |
| Online Access: | https://journals.ashs.org/hortsci/view/journals/hortsci/56/4/article-p407.xml |
| _version_ | 1818444342638936064 |
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| author | Hong-jia Xu Masafumi Johkan Toru Maruo Natsuko Kagawa Satoru Tsukagoshi |
| author_facet | Hong-jia Xu Masafumi Johkan Toru Maruo Natsuko Kagawa Satoru Tsukagoshi |
| author_sort | Hong-jia Xu |
| collection | DOAJ |
| description | With the increase in dialysis patients worldwide, the demand for low-K vegetables is growing. Thus, a type of lettuce with a low-K content has been marketed in Japan. To learn more about low-K vegetables, information is needed on the physiological differences between these vegetables and those with typical levels of potassium (K). In this study, lettuces (Lactuca sativa L.) were cultivated using two low-K management methods in an environment-controlled system. One method was based on electrical conductivity (EC) management, and the K was replaced by sodium (Na) at the end of cultivation. The other method was based on quantitative nutrient management, and the nutrients required for low-K lettuce were quantitatively supplied, but no extra Na was added. Meanwhile, lettuce with normal K concentration was cultivated with EC management as the control. Plant growth indices, leaf photosynthesis traits, chlorophyll fluorescence characteristics, concentrations of secondary metabolites (SMs), and antioxidant activity were examined to investigate the physiological effects of low-K and high-Na concentrations during low-K lettuce cultivation. Both low-K treatments significantly restrained the growth of lettuce and increased the concentration of soluble sugar. However, photosynthesis and fluorescence characteristics remained unchanged. This indicates that the biomass reduction of low-K lettuce was due to the wasteful accumulation of carbohydrates rather than the decline in photosynthesis. Concentrations of SMs were increased in the low-K lettuce. In addition, higher concentrations of Na influenced the concentration of SMs, indicating that SMs were more sensitive to environmental stress. |
| first_indexed | 2024-12-14T19:14:25Z |
| format | Article |
| id | doaj.art-17fae336366b4c15bfbd08b504fb55b4 |
| institution | Directory Open Access Journal |
| issn | 2327-9834 |
| language | English |
| last_indexed | 2024-12-14T19:14:25Z |
| publishDate | 2021-04-01 |
| publisher | American Society for Horticultural Science (ASHS) |
| record_format | Article |
| series | HortScience |
| spelling | doaj.art-17fae336366b4c15bfbd08b504fb55b42022-12-21T22:50:38ZengAmerican Society for Horticultural Science (ASHS)HortScience2327-98342021-04-01564407413https://doi.org/10.21273/HORTSCI15130-20New Insight on Low-K Lettuce: From Photosynthesis to Primary and Secondary MetabolitesHong-jia XuMasafumi JohkanToru MaruoNatsuko KagawaSatoru TsukagoshiWith the increase in dialysis patients worldwide, the demand for low-K vegetables is growing. Thus, a type of lettuce with a low-K content has been marketed in Japan. To learn more about low-K vegetables, information is needed on the physiological differences between these vegetables and those with typical levels of potassium (K). In this study, lettuces (Lactuca sativa L.) were cultivated using two low-K management methods in an environment-controlled system. One method was based on electrical conductivity (EC) management, and the K was replaced by sodium (Na) at the end of cultivation. The other method was based on quantitative nutrient management, and the nutrients required for low-K lettuce were quantitatively supplied, but no extra Na was added. Meanwhile, lettuce with normal K concentration was cultivated with EC management as the control. Plant growth indices, leaf photosynthesis traits, chlorophyll fluorescence characteristics, concentrations of secondary metabolites (SMs), and antioxidant activity were examined to investigate the physiological effects of low-K and high-Na concentrations during low-K lettuce cultivation. Both low-K treatments significantly restrained the growth of lettuce and increased the concentration of soluble sugar. However, photosynthesis and fluorescence characteristics remained unchanged. This indicates that the biomass reduction of low-K lettuce was due to the wasteful accumulation of carbohydrates rather than the decline in photosynthesis. Concentrations of SMs were increased in the low-K lettuce. In addition, higher concentrations of Na influenced the concentration of SMs, indicating that SMs were more sensitive to environmental stress.https://journals.ashs.org/hortsci/view/journals/hortsci/56/4/article-p407.xmlchlorophyll fluorescenceelectric conductivity controlflavonoidsphenolsquantitative management |
| spellingShingle | Hong-jia Xu Masafumi Johkan Toru Maruo Natsuko Kagawa Satoru Tsukagoshi New Insight on Low-K Lettuce: From Photosynthesis to Primary and Secondary Metabolites HortScience chlorophyll fluorescence electric conductivity control flavonoids phenols quantitative management |
| title | New Insight on Low-K Lettuce: From Photosynthesis to Primary and Secondary Metabolites |
| title_full | New Insight on Low-K Lettuce: From Photosynthesis to Primary and Secondary Metabolites |
| title_fullStr | New Insight on Low-K Lettuce: From Photosynthesis to Primary and Secondary Metabolites |
| title_full_unstemmed | New Insight on Low-K Lettuce: From Photosynthesis to Primary and Secondary Metabolites |
| title_short | New Insight on Low-K Lettuce: From Photosynthesis to Primary and Secondary Metabolites |
| title_sort | new insight on low k lettuce from photosynthesis to primary and secondary metabolites |
| topic | chlorophyll fluorescence electric conductivity control flavonoids phenols quantitative management |
| url | https://journals.ashs.org/hortsci/view/journals/hortsci/56/4/article-p407.xml |
| work_keys_str_mv | AT hongjiaxu newinsightonlowklettucefromphotosynthesistoprimaryandsecondarymetabolites AT masafumijohkan newinsightonlowklettucefromphotosynthesistoprimaryandsecondarymetabolites AT torumaruo newinsightonlowklettucefromphotosynthesistoprimaryandsecondarymetabolites AT natsukokagawa newinsightonlowklettucefromphotosynthesistoprimaryandsecondarymetabolites AT satorutsukagoshi newinsightonlowklettucefromphotosynthesistoprimaryandsecondarymetabolites |