Response of Tomato Fruit Quality Depends on Period of LED Supplementary Light

Abstract

Light is an important environmental factor that regulates the activity of metabolism-related biochemical pathways during tomato maturation. Using LED to improve lighting conditions during the process of tomato growth and development is a feasible and efficient method to improve the quality of tomato fruit. In this study, red and blue LEDs were used to supplement light on “MicroTom” tomato plants for different periods of time in the morning and evening, and the differences between the primary and secondary metabolites and other nutrient metabolites in the tomato fruit were analyzed using liquid chromatography and liquid chromatography mass spectrometry and other methods. Supplementing light in the morning promoted the accumulation of vitamin C, organic acids, amino acids, carotenoids, phenolic acids, and other health-promoting substances in the tomato fruits. Supplementing light in the evening significantly increased the content of sugars, flavonoids, and aromatic substances in tomato fruits, whereas the promoting effect of LED on the accumulation of amino acids and carotenoids was lower in the evening than in the morning. Both morning and evening light supplementation reduced the mineral content of fruit. In conclusion, morning light supplementation improved the nutritional quality of tomato fruits, while evening light supplementation improved their flavor.

Application of Exogenous Melatonin Improves Tomato Fruit Quality by Promoting the Accumulation of Primary and Secondary Metabolites

“…The supernatant (2 mL) was aspirated and passed through a disposable aqueous membrane with a 0.22 µm, which was used for high-performance liquid chromatography (HPLC). The HPLC conditions were based on a method by Wang et al [ 35 ]. The chromatographic column was an LC-NH2 amino column (250 mm × 4.6 mm, Waters Corp., Milford, MA, USA), the mobile phase used was V (acetonitrile): V (water) = 3:1 and its flow rate was 1.0 mL·min −1 , the column temperature was 30 °C, and the injection volume was 20 µL.…”

Application of 5-aminolevulinic acid promotes ripening and accumulation of primary and secondary metabolites in postharvest tomato fruit

“…The extraction and determination of sugar component content were performed according to the previous method in our laboratory ( 26 ). A 5 g of fresh tomato fruit samples were homogenized.…”

“…The extraction and determination of organic acid component content were performed according to the previous methods in our laboratory ( 26 ). Fresh fruit samples (5 g) were homogenized, transferred into 25 ml centrifugal tube and make the volume constant, and then centrifuged at 8,500 × g for 10 min at 4 ° C. A 2-ml supernatant was added through a 0.22-μm aqueous filter, and the filtrate was used for HPLC with a UV detector (EMpower3 2998 AcQuITY Arc, Waters, United States), The chromatographic column: Hi-PiexH (300 × 7.7 mm, Agilent Technologies, United States); the detection wavelength: 210 nm; mobile phase: dihydrogen phosphate sodium (0.2 mmol L –1 ); flow rate: 0.5 ml min –1 ; column temperature: 25 ° C; and injection volume: 10 μl.…”

“…For determination of the 11 phenols (protocatechuic acid, p-hydroxybenzoic acid, chlorogenic acid, gallic acid, 4-coumaric acid, ferulic acid, cinnamic acid, gentianic acid, caffeic acid, cynarin, and benzoic acid) and 4 flavonoids (rutin, quercetin, naringenin, and kaempferol) were performed according to the method of Wang et al ( 26 ), with slight modifications. Take 0.1 g of freeze-dried tomato sample powder, transfer to a test tube (containing 2 ml methanol), and incubate at 4 ° C for 1 h. Then centrifuged at 5,500 × g at 4 ° C for 10 min, the supernatant was added through a 0.22-μm organic filter membrane, and finally analyzed by HPLC (Alliance Waters e2695, Waters, United States).…”

Low Plant Density Improves Fruit Quality without Affecting Yield of Cucumber in Different Cultivation Periods in Greenhouse

“…How to make more use of natural light to increase the cucumber yield and improve the fruit quality in greenhouses is still a great challenge. Optimal plant density could also improve the canopy photosynthetic yield by increasing the light penetration to lower leaves in the canopy, which is beneficial for yield and fruit quality [16][17][18]. Although numerous studies have proven that changing density does have an impact on yield [19,20], there has been little plant density studies focusing on cucumber quality.…”