Effect of red and blue LED light irradiation on ascorbate content and expression of genes related to ascorbate metabolism in postharvest broccoli

Abstract

The effects of red and blue light-emitting diode (LED) lights on the senescence of broccoli (Brassica oleracea L. var. italica) after harvest were investigated. The results showed that irradiation with red LED light was effective in delaying senescence in broccoli after harvest. Under red LED light, the yellowing process was delayed, and ethylene production and reduction of ascorbate (AsA) were suppressed in broccoli after harvest. In contrast, the blue LED light treatment did not significantly affect the senescence process of broccoli after harvest. As the red light is inconvenient for customers in selecting broccoli in the supermarket, we designed a type of modified white LED light. In this modified white LED light, the ratio of blue light was decreased, while the ratio of red light was increased. Under the modified white LED light, AsA reduction in broccoli was slightly delayed on the first and second days after harvest. Moreover, the modulation of AsA reduction by the modified white LED light treatment was highly regulated at the transcriptional level. The up-regulation of the AsA biosynthetic genes (BO-VTC2 and BO-GLDH) and AsA regeneration genes (BO-MDAR1 and BO-MDAR2) contributed to the higher AsA content in the modified white LED light treatment on the first and second days after harvest. The results presented might provide new strategies to improve the nutritional quality of broccoli after harvest.

While continuous white LED lighting increases chlorophyll content (SPAD), green LED light reduces the infection rate of lettuce during storage and shelf-life conditions

“…Warm‐white LED (1.4 µE m −2 s −1 ) delayed the chlorophyll degradation in Lamb's lettuce ( Valerianella olitoria L. Pollich) (Braidot et al, ). A similar effect was observed in broccoli with red light (660 nm) (Ma et al, ). Therefore, both white (in lettuce) and red lighting (in broccoli) can reduce senescence.…”

“…Red light is absorbed by members of cryptochrome and phototropin photoreceptors (Bohne & Linden, ; Lin, ). Therefore, red and blue lights produce different morphogenetic and photosynthetic responses in plants (Ma et al, ). In the present study, blue light inhibited increasing green color, whereas the red light promoted green color.…”

Effect of LED irradiation on the ripening and nutritional quality of postharvest banana fruit

“…15 Sensing of light in higher plants is carried out by different light photoreceptors; different wavelengths of light might thus have distinct effects on plant growth and development. 24 Blue light is absorbed by cryptochrome and phototropin photoreceptors, 30 and controls many plant responses including chloroplast development, chlorophyll formation, stomata opening, shoot growth, leaf expansion and biomass production. 31 An increase in the concentration of glucose in tomato fruit by blue LED irradiation had been observed.…”

Inhibition of Botrytis cinerea and accumulation of stilbene compounds by light-emitting diodes of grapevine leaves and differential expression of defense-related genes

“…Several photoreceptors have been revealed in fungal systems (Corrochano 2007;Herrera-Estrella and Horwitz 2007), and it has been suggested that photoexcitation of natural photosensitizer porphyrins might lead to photoinactivation of grey mold after infection (Imada et al 2014). It has also been reported that red and blue light produced different morphogenetic and photosynthetic responses in plants (Ma et al 2014).…”

“…Many studies have reported that the expression of genes related to defense and the secondary metabolite biosynthesis pathway was regulated under light (Chamnongpol et al 1996;Ebisawa et al 2008;Ma et al 2014;Schmidlin et al 2008;Zhou et al 2013). Induction of disease resistance response to pathogens by exposing plants to several light-emitting diodes (LEDs), including blue, green, yellow, and red, has been reported in plants (Imada et al 2014;Islam et al 1998;Kudo et al 2009Kudo et al , 2011Suthaparan et al 2010b;Upadhyaya 2013).…”