Effects of exposing Spodoptera litura (Lepidoptera: Noctuidae) to flashing colored LED lights during the scotophase on the growth, development and reproduction of this species
Author of the article:ZHONG Chun-Lan, ZHU Di-Fu, CHENG Yu-Meng, LIU Zi-Hang, FU Zi-Xin, WANG Jian-Ying, GONG Hui-Rong, TU
Author's Workplace：College of Life Sciences, Jiangxi Normal University, Nanchang 330022, China
Key Words：Spodoptera litura; flashing; LED light; growth and development; reproduction
Abstract：[Objectives] To
understand the effects of exposure to flashing, colored LED lights during the
scotophase on the growth, development and reproduction of Spodoptera litura. [Methods] Insects were randomly assigned to one of three
treatment groups: 14L:10FR-G-B-2.5Hz, 14L:10FR-G-B-Y-P-W-2.5Hz and
14L∶10FR-G-B-Y-P-W-0.5Hz (R, G, B, Y, P and W
represent red, green, blue, yellow, purple and white light respectively, and
the numeric subscripts 2.5 and 0.5 represent the light conversion frequency of
different colored LEDs). The control group was kept under a standard
photoperiod of 14L∶10D. The
durations of the egg, larval and pupal stages, adult longevity, number of eggs laid per
female, hatching rate, pupation rate
and adult eclosion rate, were recorded and compared. [Results] Exposure to flashing colored
LED lights in the scotophase had no significant effect on the hatching rate,
pupation rate or adult eclosion rate (P>0.05). There were also
no significant effect on the duration of the egg or female larval
stages (P>0.05), but the duration of the male larval stage
was significantly prolonged by the 14L∶10FR-G-B-2.5Hz treatment (22.5 d) compared to the control. Pupal duration in
all three treatment groups was significantly longer (♀: 19.0, 19.6 and 18.9 d; ♂:
22.4, 23.2 and 22.0 d) than in the control (♀: 18.2 d;
♂: 20.8 d) (P=0.000). Male pupal
duration was significantly longer than female pupal duration (P=0.000),
and male pupal weights in the 14L∶10FR-G-B-2.5Hz treatment
group (0.227 g) and 14L∶10FR-G-B-Y-P-W-2.5Hz treatment group (0.228 g) were significantly heavier than those of the
control group (0.216 g). Adult
longevity and the pre-oviposition period of all three treatment groups were
significantly prolonged (adult longevity: ♀: 16.8, 18.2 and 16.8 d; ♂:
18.3, 18.1and 19.3; pre-oviposition
period: 5.2, 6.1 and 5.1 d)
compared to the control group (adult
longevity: ♀13.1 d, ♂13.3 d; pre-oviposition period: 3.2 d; P<0.05). However, exposure to flashing, colored LED lights had no
significant effect on the oviposition period or the number of eggs laid per
female. [Conclusion] Exposure
to flashing, colored LED lights (10 lx) during the scotophase affected the
growth and development of S. litura, especially the duration
of the male larval stage, the duration of the female and male pupal stage, and adult longevity. Effects varied
with the color of the LED lights and the frequency at which they flashed.
However, exposure to flashing, colored LED lights had little effect on the
reproduction of S. litura.