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Lethal effects of short-wavelength visible light on insects.

Hori M, Shibuya K, Sato M, Saito Y - Sci Rep (2014)

Bottom Line: We investigated the lethal effects of visible light on insects by using light-emitting diodes (LEDs).Blue light was also lethal to mosquitoes and flour beetles, but the effective wavelength at which mortality occurred differed among the insect species.For some animals, such as insects, blue light is more harmful than UV light.

View Article: PubMed Central - PubMed

Affiliation: Graduate School of Agricultural Science, Tohoku University, Sendai 981-8555, Japan.

ABSTRACT
We investigated the lethal effects of visible light on insects by using light-emitting diodes (LEDs). The toxic effects of ultraviolet (UV) light, particularly shortwave (i.e., UVB and UVC) light, on organisms are well known. However, the effects of irradiation with visible light remain unclear, although shorter wavelengths are known to be more lethal. Irradiation with visible light is not thought to cause mortality in complex animals including insects. Here, however, we found that irradiation with short-wavelength visible (blue) light killed eggs, larvae, pupae, and adults of Drosophila melanogaster. Blue light was also lethal to mosquitoes and flour beetles, but the effective wavelength at which mortality occurred differed among the insect species. Our findings suggest that highly toxic wavelengths of visible light are species-specific in insects, and that shorter wavelengths are not always more toxic. For some animals, such as insects, blue light is more harmful than UV light.

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Comparison of the lethal effects of light irradiation on Drosophila melanogaster pupae using various wavelengths of LED light.(a) Mortality of pupae irradiated with 3.0 × 1018 photons·m−2·s−1. Data are means ± standard error (SE). Different lowercase letters next to bars indicate significant differences (Steel–Dwass test, P < 0.05). LL, DD, and LD indicate 24-h light, 24-h dark, and 16L:8D photoperiod conditions, respectively. (b) Dose–response relationships for lethal effects of irradiation on pupae for each wavelength. Data are mean values.
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f1: Comparison of the lethal effects of light irradiation on Drosophila melanogaster pupae using various wavelengths of LED light.(a) Mortality of pupae irradiated with 3.0 × 1018 photons·m−2·s−1. Data are means ± standard error (SE). Different lowercase letters next to bars indicate significant differences (Steel–Dwass test, P < 0.05). LL, DD, and LD indicate 24-h light, 24-h dark, and 16L:8D photoperiod conditions, respectively. (b) Dose–response relationships for lethal effects of irradiation on pupae for each wavelength. Data are mean values.

Mentions: First, we investigated the lethal effect of light (wavelengths from 378 to 732 nm) on D. melanogaster pupae using LEDs. Irradiation with wavelengths of 378, 417, 440, 456, and 467 nm at 3.0 × 1018 photons·m−2·s−1 throughout the pupal stage significantly increased the mortality of D. melanogaster pupae compared with their mortality under DD (24-h dark) conditions (Fig. 1a, Supplementary Table 1). In particular, we identified two peak wavelengths (440 and 467 nm; Fig. 1a) that had strong lethal effects. More than 90% and 70% of pupae died before adult emergence after irradiation with wavelengths of 467 and 440 nm, respectively; the lethal effects of these wavelengths were stronger than those of UVA (378 nm). Wavelengths of 404 nm and ≥496 nm did not have a lethal effect on D. melanogaster pupae (Fig. 1a, Supplementary Table 1). In wavelengths ranging from 378 to 508 nm, mortality increased with increasing numbers of photons (Fig. 1b). Wavelengths of 440, 456, and 467 nm led to 100% mortality at 4.0 × 1018 photons·m−2·s−1; this number of photons did not have a lethal effect at wavelengths of 508, 657, and 732 nm. These results reveal, for the first time, that complex animals such as insects can be killed by irradiation with certain wavelengths of visible light, and that visible light is more harmful than UV light to some animals.


Lethal effects of short-wavelength visible light on insects.

Hori M, Shibuya K, Sato M, Saito Y - Sci Rep (2014)

Comparison of the lethal effects of light irradiation on Drosophila melanogaster pupae using various wavelengths of LED light.(a) Mortality of pupae irradiated with 3.0 × 1018 photons·m−2·s−1. Data are means ± standard error (SE). Different lowercase letters next to bars indicate significant differences (Steel–Dwass test, P < 0.05). LL, DD, and LD indicate 24-h light, 24-h dark, and 16L:8D photoperiod conditions, respectively. (b) Dose–response relationships for lethal effects of irradiation on pupae for each wavelength. Data are mean values.
© Copyright Policy - open-access
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC4260232&req=5

f1: Comparison of the lethal effects of light irradiation on Drosophila melanogaster pupae using various wavelengths of LED light.(a) Mortality of pupae irradiated with 3.0 × 1018 photons·m−2·s−1. Data are means ± standard error (SE). Different lowercase letters next to bars indicate significant differences (Steel–Dwass test, P < 0.05). LL, DD, and LD indicate 24-h light, 24-h dark, and 16L:8D photoperiod conditions, respectively. (b) Dose–response relationships for lethal effects of irradiation on pupae for each wavelength. Data are mean values.
Mentions: First, we investigated the lethal effect of light (wavelengths from 378 to 732 nm) on D. melanogaster pupae using LEDs. Irradiation with wavelengths of 378, 417, 440, 456, and 467 nm at 3.0 × 1018 photons·m−2·s−1 throughout the pupal stage significantly increased the mortality of D. melanogaster pupae compared with their mortality under DD (24-h dark) conditions (Fig. 1a, Supplementary Table 1). In particular, we identified two peak wavelengths (440 and 467 nm; Fig. 1a) that had strong lethal effects. More than 90% and 70% of pupae died before adult emergence after irradiation with wavelengths of 467 and 440 nm, respectively; the lethal effects of these wavelengths were stronger than those of UVA (378 nm). Wavelengths of 404 nm and ≥496 nm did not have a lethal effect on D. melanogaster pupae (Fig. 1a, Supplementary Table 1). In wavelengths ranging from 378 to 508 nm, mortality increased with increasing numbers of photons (Fig. 1b). Wavelengths of 440, 456, and 467 nm led to 100% mortality at 4.0 × 1018 photons·m−2·s−1; this number of photons did not have a lethal effect at wavelengths of 508, 657, and 732 nm. These results reveal, for the first time, that complex animals such as insects can be killed by irradiation with certain wavelengths of visible light, and that visible light is more harmful than UV light to some animals.

Bottom Line: We investigated the lethal effects of visible light on insects by using light-emitting diodes (LEDs).Blue light was also lethal to mosquitoes and flour beetles, but the effective wavelength at which mortality occurred differed among the insect species.For some animals, such as insects, blue light is more harmful than UV light.

View Article: PubMed Central - PubMed

Affiliation: Graduate School of Agricultural Science, Tohoku University, Sendai 981-8555, Japan.

ABSTRACT
We investigated the lethal effects of visible light on insects by using light-emitting diodes (LEDs). The toxic effects of ultraviolet (UV) light, particularly shortwave (i.e., UVB and UVC) light, on organisms are well known. However, the effects of irradiation with visible light remain unclear, although shorter wavelengths are known to be more lethal. Irradiation with visible light is not thought to cause mortality in complex animals including insects. Here, however, we found that irradiation with short-wavelength visible (blue) light killed eggs, larvae, pupae, and adults of Drosophila melanogaster. Blue light was also lethal to mosquitoes and flour beetles, but the effective wavelength at which mortality occurred differed among the insect species. Our findings suggest that highly toxic wavelengths of visible light are species-specific in insects, and that shorter wavelengths are not always more toxic. For some animals, such as insects, blue light is more harmful than UV light.

Show MeSH
Related in: MedlinePlus