insect orientation to various colors of lights in sampaloc, san rafael, bulacan
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Insect orientation to various colors of lights in Sampaloc, San Rafael, Bulacan ThesisTRANSCRIPT
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INSECT ORIENTATION TO VARIOUS COLORS OF LIGHTSIN SAMPALOC, SAN RAFAEL, BULACAN
____________________
A Research Project Presented toMr. Oliver Alaijos
BIO 223B InstructorBulacan State UniversityCity of Malolos, Bulacan
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In Partial Fulfilment of the Course Requirement in BIO 223BBachelor of Science in Biology
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byRenzel T. Santiago
BS BiologyMarch 2014
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Insect Orientation to Various Colors of Lights in Sampaloc, San Rafael, Bulacan
ABSTRACT
Ecological light pollution has a major impact on millions of insects throughout the
world. The flight-to-light response occurs when nocturnal insects fly towards an artificial light.
The purpose of this study was to determine if insects would show equal flight-to-light response to
different wavelengths of the light spectrum. Fluorescent lights from different parts of the
spectrum were placed in a fabric screen and left on for 3 hours in order to attract the insects for
the experiment. One red light, one green light, one blue light, and one ultraviolet light were used
for the experiment; these four lights covered a large portion of the visible light spectrum. The
experiment was carried out in a vegetable field, in an open space, and near the irrigation site to
see if the species diversity attracted to each light varied from region to region. It was expected
that the ultraviolet light would attract the greatest number as well as the most diverse group of
insects because insect vision is shifted towards the shorter end of the light spectrum when
compared to human vision. However, the blue light attracted to largest number as well as most
diverse group of insects, possibly because it is in the center of the light spectrum visible to
insects.
Key words: artificial light; flight-to-light; light trap; ultraviolet; light pollution
INTRODUCTION
Humans have been searching for ways to illuminate the night for millennia. Until the
invention of electric lights, the affect of the light on the ecosystem was fairly small. However, in
the present day, artificial light has completely altered the night-time environment throughout
much of the world. The altering of the environment from artificial light sources is known as
ecological light pollution. Ecological light pollution has a major effect on the behaviour and
population of many organisms. Overall, these effects come from changes in orientation and the
attraction or repulsion from the artificial light. This can affect reproduction, communication,
foraging, and migration (Longcore & Rich 2004).
It is well known that a wide variety of insects are affected by artificial light. One of the
most known affects is the “flight-to-light” response. This is when organisms are attracted to light
even at their peril. There are two hypotheses for this response. The first is the Compass Theory.
This theory states nocturnal insects use celestial light to orient themselves in order to fly in a
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straight line. The divergent beams from the artificial light cause the insect to spiral ever closer to
the light. The other hypothesis is the Open Space Theory. This theory assumes insects fly to open
space for their nightly actions. Open spaces are generally brighter because trees are not blocking
the celestial light. Insects mistake artificial lights for open spaces and then fly to them (Altermatt
et al. 2009).
Background
To fully understand the concept of this experiment, background knowledge of light and
insects is essential. There are seven colors in the light spectrum: red, orange, yellow, green, blue,
indigo and violet. Four of these were used in the experiment (red, green, blue, and ultraviolet).
These seven colors lights are known as visible lights (Henderson, 1996). Each light color has a
different wavelength and frequency. Red has the longest wavelength and lowest frequency and
violet has the shortest wavelength and highest frequency. The wavelengths of visible lights range
from 400-700 nanometers (White, 1980; Ditchburn, 2001).
Insect vision uses the same basic mechanism as human sight for color recognition, but it
also has some dramatic differences from the way humans perceive the same objects. All insects
have compound eyes that are composed of hundreds to thousands of individual facets. Behind
each facet is an ommatidium composed of three components: the optical system, pigment cells,
and retinula cells (Evans 1984). Inside the retinular cell group is a protein called rhodopsin,
which is responsible for how the insect perceives color based on its chemical make-up and how
the protein has folded (Evans 1984). Different rhodopsins react to different portions of the light
spectrum, and most insects have rhodopsins that are sensitive to three spectral classes (Daly
1998). There is some variance between different species of insects as to where the three ranges of
spectral absorbance fall, but based on an absorbance curve, maximum absorption occurs at
around 350nm, 460nm, and 550nm for most insects (Menzel 1975). “Although the color vision
of insects is trichromatic like our own, their visual world is different because the spectrum is
shifted towards the shorter wavelengths to include ultraviolet. Except for butterflies, most insects
lose their ability to distinguish differences in wavelengths between 550 and 650 nm (Daly 1998).”
This fact has a major impact on the attractive ability of certain colors of light and especially the
red light, which falls into part of the 550nm to 650nm range. The sensitivity to ultraviolet light is
much higher in most insects than their ability to distinguish light from the blue or green regions
of the spectrum (Menzel 1975). Many flowers take advantage of this ability of insects to see
ultraviolet light by having attractive patterns that only insects, which are pollinators, can see
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(Daly 1998). Consequently, many insects may be drawn to light from the ultraviolet end of the
spectrum thinking that it leads to a potential food source such as the nectar from a flower.
Objectives
This research was conducted to determine which wavelength of light will attract the most
insects and which will attract the most diverse group of insects. This study will serve as an
inventory of what insect orders could be found at the specific location. It would also help in
identifying the insects that are attracted to artificial light source and to classify whether the insect
is night-active (nocturnal) or day-active (diurnal). And also, this will also provide a proof that
passive collection of insect using light traps is a useful technique in studying the diversity of
insects.
Hypothesis
Most insects have the greatest visual acuity in the short wavelength end of the spectrum,
a greater number as well as a more diverse group of insects should be attracted to the ultraviolet
light because it covers portions of both the visible and ultraviolet spectrums. The blue light
should have the second greatest number of insects and the red the least because it emits the
longest wavelength light. Diversity tests will help indicate which light has attracted the greatest
variety of insects, regardless of the total number caught by the trap.
Review of Related Study
The results of experiments done by Jessica and Curtis 2001 are similar to my study. They
have been found to be highly convincing that red light with low frequency and high wavelength
attracts the lowest number of insects. Accordingly, the black light (ultraviolet) with high
frequencies and low wavelength was observed to attract the highest number of insects. Similar
pattern of insect orientation toward light has been observed by Luettich 2003 in his experiment
conducted in Wilmington, North Carolina, USA, however, the number of insect responded was
found to be less than present study (Jessica and Curtis 2001).
In the years 1998 and 2000, similar experiments were done at different places, and with
similar results. In 1998, at Chimney Rock in Rutherford County, North Carolina, the results were
the same, but the number of insects caught was lower. The conditions at Chimney Rock were
partly cloudy and 78 degrees Fahrenheit. The experiment lasted for thirty-five minutes, from
9:54-10:29 pm. In 2000, at Mt. Jefferson in Ashe County, North Carolina, the results were
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almost the same. The conditions were 50-55 degrees Fahrenheit and the experiment lasted from
10:30-11:10 pm. The only difference was that the white light caught more insects than the blue
light. Reasons for this could be a difference in temperature, spacing of the lights or human error
(Jessica and Curtis 2001).
Bellrichard, (2009) experiment showed no significant difference between the different
colored lights for most insect orders. The only group with a significant difference was the order
Lepidoptera were more attracted to the white light. However, even though they did not find a
significant difference their data does follow the trend they expected.
MATERIALS AND METHODS
Study Sites
The investigations were carried out from 4th week of December, 2013 to 3rd week of
January, 2014 in the fields of Zone 1 Sampaloc, San Rafael, Bulacan. The light trap was placed in
three different locations (Figure 1). The Site I (Lat: 14° 59' 14.892" Long: 120° 55' 25.5504")
was in the vegetable fields (Figure 3), Site II (Lat: 14° 59' 15.8418" Long: 120° 55' 24.3588")
was in an open space with no trees and plants blocking the trap (Figure 4), and Site III (Lat: 14°
59' 12.4002" Long: 120° 55' 24.582") was in the rice fields near the irrigation area (Figure 5).
The Light Trap
Four different light sources were used in this experiment, Ultraviolet light (325-400nm),
Blue light (450-495nm), Green light (495-570nm), and Red light (620-750nm). The light trap had
five constituent parts, namely, a.) Fabric screen constructed into semi-pyramidal shape and
slanted 1.5 meter high above ground to allow entry of insects inside b.) Light source, in different
wavelengths c.) Metallic foil is use to scatter the light d.) White blanket, placed below the trap to
easily gather the attracted insects e.) Opaque cover, placed above the light source to prevent
insects to perch outside the net. The light trap is 2 feet in height and its base was 1.5 square
meters wide (See Figure 2).
The Experiment Procedure
This experiment was conducted at night from 9:00 to 9:30 hours in the dark. In order to
cover diversity of crops and vegetable vegetation, three areas i.e. vegetable, open and rice field
were selected for the layout of said experiment. Each of the four lights was operated one per night
at each site to let the insect to orientate toward a specific light color. All lights were
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simultaneously kept on for 3 hours and each of them was suitably placed on white fabric screen in
semi-pyramidal shape. The trap was hang 1.5 meters high above ground to be visible from
distance and was placed away from any other source of light to avoid discrepancy on the result. A
white blanket was placed under the trap to gather the attracted insects. After 3 hours, the trap will
be put down so the trapped insects would not escape from it. An insecticide was sprayed to the
fabric screen with insects on it then after a minute, the insects will fell down onto the blanket
(Figure 13). At the end of experiment, insects were transferred to a kill jar and collection was
transferred to container for identification. Contents of each container were examined, exact
number of insects was counted and each of them was identified for respective insect order
(Pedigo 1996). The same procedure was adopted for all containers containing insect collection
gathered at each light color. Most of the insects were identified by naked eye and field lens (10x)
was also used where needed to confirm the diagnostic feature of smaller insects. The data were
tabulated as percentages of insects attracted per light color and overall number of insect order
collected at each light spectrum according to the following criterion (White 1989).
The materials used during experimentation included tube lights in four colors, white
blanket, fabric screens, storage bottles or containers, lens, source of electricity, kill jars, forceps,
etc (Figure 14).
Guide to the Insect Orders and Curation Methods
Careful pinning of relaxed insects will greatly enhance their safekeeping. Insects should
be pinned on foam blocks that provide support for the body as it dries as well as allowing for
wings, legs, and antennae to be positioned close to the body making them less likely to be
knocked off when moved. Insects that take up less space can be pinned closer together and thus
stored more efficiently. After drying, the specimen is handled only by the pin and adequate space
must be left above the specimen (Dunn, 1994).
Pins are placed as follows:
Blattodea – Cockroaches: Pin through right tegmen (spreading left wing optional).
Mantodea – Mantises: Pin through right side of mesothorax (spreading left wing optional.)
Dermaptera – Earwigs: Pin through right tegmen, point small specimens.
Orthoptera
Orthoptera: Caelifera – (Short-horned, Lubber & Pygmy grasshoppers): Pin through right
side of mesothorax (spreading left wing optional).
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Orthoptera: Ensifera – (Crickets, Katydids, Mole Crickets & Cave Crickets): Pin through
right side of mesothorax (spreading left wing optional).
Hemiptera
Hemiptera: Heteroptera – (True bugs): Pin through right side of scutellum, point smaller
specimens.
Hemiptera: Auchenorrhyncha – (Cicadas & Hoppers): Pin through right side of scutellum,
point smaller specimens.
Coleoptera – Beetles: Pin through anterior portion of the right elytra. Point smaller
specimens.
Diptera: Nematocera – (Long-horned flies Crane flies, Mosquitoes, Midges): Pin through
right side of thorax using insect pin, spread wings or tuck them back against the body. Point
thin or small specimens.
Lepidoptera – Butterflies & Moths: Pin through center of thorax using insect pin, spread
wings so that posterior margin of forewing is perpendicular to body and the hind- wing is
pulled forward to form a slight ‘v’ between wings as shown.
Hymenoptera – Ants, Bees & Wasps: Pin through right side of thorax using insect pin (wings
should be tucked back against body as they are at rest in live specimens or spread). Point
smaller specimens including all ants (Figure 15).
RESULTS AND DISCUSSIONS
Figure 9 represent the percentages of the total numbers of insects caught at each colored
light. Four colors of light are used at each site. Total collection of insects per light color was
added up separately for each site and then percentage of insects attracted at each light spectrum
was computed to be tabulated in Figure 6, 7 and 8. Finally, the percentage of insects oriented
toward different light colors were separately added for respective light colors to compute the
cumulative percentage of insect attracted per light color for more comprehensive and precise
results (See Figure 6 - 9).
According to the cumulative percentages of insect collection gathered per night, the
lowest number of insects has been attracted at red color light i.e. 12.10% and second to the lowest
is green light of 13.60%. Ultraviolet light attracted the highest figure of 29.60% insects. Blue
light was rated to attract the second highest insect numbers of 44.0% at different sites.
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The data collected at different study sites have given similar results of insect orientation
toward specific light colors. This phenomenon certifies the validity of the generated data.
Figure 10 shows the order distribution of insects attracted at red, green, blue and
ultraviolet lights. The ultimate aim of this research study was to identify the most effective light
color that could attract the highest number of insects at night. Thus, the field data strongly
convince about ultraviolet and blue lights to be highly effective in attracting diversity and number
of insects and green and red light was the lowest. It was necessary to segregate the insect
collection of these four light colors into respective insect orders to provide useful information for
further studies.
According to Figure 10, all four lights have been found to attract almost all the nine
insect orders, however the members of Coleoptera, Hemiptera and Orthoptera were found to be
attracted in higher number (Figure 18, 19, and 20). The Coleopterus insects were attracted in the
highest number i.e. 45 and have been found responding ultraviolet light whereas lowest number
of 3 responded to red color. The Orthopterus insects were counted to be 33 and appeared as the
second highest number on ultraviolet light. Hemipterus insects were rated to be at third place with
the highest number of 32 insects. The data on different sites show that all insects followed the
same pattern of attraction for all four colored lights (the red, green, blue and ultraviolet). The
efficiency of the four light sources on different insect orders was tabulated on Figure 11.
The results showed that most of the orders were attracted to blue and ultraviolet lights
(Thomas 1996). This attraction is merely due to shorter wavelengths and higher frequency while
the red light is otherwise which makes it harder for the insects to detect. Insects have three special
eyes, called ocelli, with the specific job of identifying light and not movement (Burnie 2003). The
shorter the wavelengths are easier for the ocelli to detect (Henderson 1996, Burnie 2003).
This attraction to ultraviolet light has made insects a useful model for understanding
visual sensitivity to ultraviolet light (Stark and Tan, 1982). The optical properties of their eyes are
designed so that receptors make use of ultraviolet light (Smola and Meffert 1975). Behavioural
and electrophysiological experiments found that the insect eye responds to ultraviolet irradiation
(Hamdorf et. al 1971). This response leads to several different reactions. When insects are
exposed to light they may go toward or away from the source of illuminations (positive or
negative phototaxis), they may increase or decrease the rate of their general activity, and they
may change their posture or move only part of the body (Bertholf 1940).
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Insects are capable of detecting ultraviolet and colors using photoreceptors. Bees and
ants are able to simultaneously receive information from the wavelength and e-vector (vector
representing the electric field of an electromagnetic wave) of incoming light using its receptors.
Determination of Species
In this study of light attraction of insects in various colors of light, the following insect
species have been collected, namely, Lytta aenea or Blister Beetle (BugGuide, 2004),
Oryctes rhinoceros or Coconut Rhinoceros Beetle (InsectIdentification.org, 2014), and
Cotinus nitida or June Beetle (BugGuide, 2006), Brumoides septentrionis or Lady Beetle
(BugGuide, 2007), Pygoluciola satoi or Firefly (Ballantyne, 2008), Pleocoma fimbriata or Rain
Beetle (BugGuide, 2008), for the order Coleoptera; Acanalonia conica or Green Planthopper,
Scolops sulcipes or Meadow Planthopper (Leafhome, 2008), Leptocentrus Taurus or Thorn
Mimic Treehopper (ProjectNoah, 2013) , Lopidea media or Plant Bugs, Mecidea major or Stink
Bugs (AustinBug, 2001), Leptoglossus occidentalis or Leaf-footed Bugs, Euthochtha galeator or
(CedarCreek, 2014) for the Hemiptera; Scudderia furcata or Fork-Tailed Bush Katydid
Conocephalus fasciatus or Slender Meadow Katydid, Melanoplus femurrubrum or Red-legged
Grasshopper, Melanoplus differentialis or Differential Grasshopper, Achurum carinatum or Long-
headed Toothpick Grasshopper (BugGuide, 2009), Neocurtilla hexadactyla or Mole Cricket
(WhatsThatBug, 2014), Acheta domestica or House Cricket (DiscoverLife, 2014) under the
Orthoptera; Caenurgina erechtea or Forage Looper Moth, Eumorpha vitis or Sphinx Moth,
Caenurgina erechtea or Forage Looper Moth (DiscoverLife, 2014), Hypoprepia fucosa or Lichen
Moth, and Pleuroprucha insulsaria or Common Tan Wave (BugGuide, 2004) for the
Lepidoptera; and other insect orders like Mantis religiosa or Praying Mantis (MySpecies, 2008)
Mantodea; Periplaneta Americana or American Cockroach (WorldofPestControl, 2009)
Blattodea; and Labia minor or Lesser Earwig Dermaptera (WhatWhenHow, 2007).
And also some Philippine endemic species have been caught, namely, the Potanthus
niobe niobe or Grass Skipper, Poanes hobomok or Hobomok Skipper under the Lepidoptera; the
Chrysodema manillarum or Jewel Beetle, Rhynchocoris longirostris or Citrus Stink Bug,
Rhynchocoris longirostris Stål or Citrus Stink Bug, Kallitaxila granulate or Grainy Planthoppers,
Dysdercus (Paradysdercus) poecilusor or Cotton Stainer for the Hemiptera; Amata sp. or Amata
Wasp Moth for the Hymenoptera (ProjectNoah, 2013).
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CONCLUSION
The greatest number and most diverse group of insects were not attracted to the red light
as was expected; rather the ultraviolet light seemed to have the broadest and strongest attraction
in every site of the study. This difference between expectations and results could be because the
ultraviolet light is one of the colors for which an insect’s trichromatic vision has receptors. These
receptors cover the end portion of the spectrum that is visible to insects but not true with the
human eye. The light can affect both the receptors for ultraviolet light as well as the receptors for
visible light with longer wavelength, blue, green and red light (visible spectrum). Therefore,
insect’s vision is more affected by wavelength shorter than that of the visible light, but with the
highest frequency.
The fact that some insects were attracted to the red light even though their vision does not
have receptors for red light is because there must be a small amount of overlap between the top
end of the insect’s vision and the shortest wavelength light emitted by the red light. The amount
of light not completely in the red area of the spectrum that was emitted by the light would be very
small since the light appears to be mostly red, a theory that is supported by how few total insects
were drawn to the red trap (Potter, 2002).
Collections of insect using a light trap provide significant clue to the diversity of insects
active at night, their respective affinity to different wavelengths of light and to understand and
predict how populations function (Southwood and Henderson, 2000).
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REFERENCES
Longcore, T. & Rich, C. (2004).Ecological light pollution. Frontiers in Ecology and the
Environment, 2, 191-198.
Altermatt, F., Baumeyer, A., & Ebert, D. (2009). Experimental evidence for male biased flight-
to-light behavior in two moth species. Entomologia Experimentalis et Applicata, 130, pp.
259–265.
White, E.G. (1989). Light trapping frequency and data analysis – a reply. New Zealand
Entomologist 12: pp. 91-94.
Ditchburn, R.W. (2001). Light. Encyclopedia Britannica. Retrieved March 02, 2014 from the
World Wide Web. .www.britanica.com/eb/article?eu=119359&tocd=0.
Evans, H. (1984). Insect Biology: A textbook of entomology. Reading, Massachusetts: Addison-
Wesley.
Daly, H.V., J.T. Doyen, and A.H. Purcell. (1998). Introduction to insect biology and diversity.
New York: Oxford University Press.
Menzel, R. (1975). Colour receptors in insects. In G.A. Horridge (Ed.), The compound eye and
vision in insects. pp. 121-154. London: Oxford University Press.
Jessica P. and Curtis A. (2001). Insect Response to different wavelengths of light in New River
State Park, Ashe County, North Carolina, USA.
Bellrichard, M. (2009). Insect attraction to different colored lights near Lake Itasca State Park. p.
4.
Pedigo L.P. (1996). Entomology and pest management. Prentice Hall, Upper Saddle River, NJ
07458. USA.
Dunn, G. A. (1994). A Beginner’s Guide to Observing and Collecting Insects. Young Entomolo-
gist’s Society, Lansing, MI.
Thomas, A.W. (1996). Light trap catches within and above the canopy of a north eastern forest.
Journal of Lepidopterist’s Society 50: pp. 21-45.
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Burnie, D. (2003). Insects. Retrieved March 05, 2014 from http://encarta.msn.com/encnet/
refpages/refarticle.aspx.
Henderson, Tom. (1996). “Color and vision” the physics classroom. Retrieved March 02, 2014
from the World Wide Web. http://www.glenbrook.k12.il.us/gbssci/phys/class/light/
u1212a.htm.
Stark, W. S. and Tan, K.W.P. (1982). Ultraviolet light: photosensitivity and other effects on the
visual system. Photochem. Photobiol. pp. 371–380.
Smola, U. and Meffert, P. (1975) A Single-peaked UV-Receptor in the eye of calliphora
erythrocephala. J. Comp. Physiol. 103. pp. 353-357.
Hamdorf, K., Schwemer, J., and Gogala, M. (1971). Nature. 231, pp. 458-459.
Bertholf, L.M. (1940). Reactions to light in insects. Bios.1940. 11. pp. 39-43.
Potter, D. (2002). Insect responses to light of different wavelengths in two different regions of
north carolina. pp. 5-6. North Carolina.
Southwood, T. R. E. & Henderson, P. A. 2000. Ecological methods. Blackwell Science, UK. p
269- 292.
Determination of Species
Ballantyne. L. A. (2008). Pugoluciola satoi, a new species of the rare southeast asian firefly
genus pygoluciola wittmer (coleopteran: lampyridae: luciolinae) from the Philippines.
The Raffles Bulletin of Zoology 2008. Singapore.
Bug Guide. Order coleoptera. Retrieve March 23, 2014 from the World Wide Web http://
bugguide.net/node/view/60.
Insect Identification. (2014). Coconut rhinoceros beetle. Retrieve March 23, 2014 from the
World Wide Web. http://www.insectidentification.org/insect-description.asp?
identification= Coconut-Rhinoceros-Beetle.
Cedar Creek. (2014). Order hemiptera. Retrieve March 23, 2014 from the World Wide Web
http://cedarcreek. umn.edu/insects/orderpages/020page.html.
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Austin Bug. (2001). True bugs. Retrieve March 23, 2014 from the World Wide Web http://www.
austinbug.com/larvalbugbio/bugs.html.
Discover Life. (2014). Orthoptera: Grasshoppers; locusts; crickets; katydids. Retrieve March 23,
2014 from the World Wide Web http://www.discoverlife.org/mp/20q?search=Orthoptera.
Whats That Bug. (2014). Mole cricket from the Philippines. Retrieve March 23, 2014 from the
World Wide Web http://www.whatsthatbug.com/2014/02/12/mole-cricket-philippines/.
Discover Life. (2014). Lepidoptera: Butterflies; moths; skippers; caterpillars; borers;
webworms; cankerworms; bagworms. Retrieve March 23, 2014 from the World Wide
Web http://www.discoverlife.org/20/q?search=lepidoptera.
My Species. (2008). Mantis study group. Retrieve March 23, 2014 from the World Wide Web
http://mantodea.myspecies.info/identification-praying-mantids.
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World Wide Web http://www.worldofpestcontrol.com/Identification-Cockroach.html.
What-When-How. (2007). Dermaptera (earwigs) (insects). Retrieve March 23, 2014 from the
World Wide Web (http://what-when-how.com/insects/dermaptera-earwigs-insects/.
Project Noah. (2013). The Philippine endemic species. Retrieve March 17, 2014 from the World
Wide Web. https://www.projectnoah.org/missions/8621911.
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APPENDIX
Figure 1: Location: Entomofauna study sites in the fields of Sampaloc, San Rafael, Bulacan. Red represents the vegetable field (Site I), Blue is the open space (Site II), and Green is the rice field near the irrigation site (Site III).
Figure 2: Light Trap. A. Inside view showing the white blanket and the elevation of 1.5m. B. Top view showing the Opaque cover. C. Light source and metallic foil. D. Fabric screen.
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Study Sites
Figure 3: Site I: Vegetable field.
.Figure 4: Site II: Open space.
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Figure 5: Site III: Rice field near irrigation site.Percentage of insects
Site I
Color of Light PercentageRed 14.80%Green 16.70%Blue 33.30%Ultraviolet 35.20%Total insects caught 61
Figure 6: Percentage of insects attracted at different colored light during night hours in the vegetable field from December 26 to 29, 2013.
Site II
Color of Light PercentageRed 8.60%Green 8.60%Blue 22.20%Ultraviolet 60.60%Total insects caught 44
Figure 7: Percentage of insects attracted at different colored light during night hours in the open space from January 03 to 06, 2014.
Site III
Color of Light PercentageRed 12.80%Green 15.40%Blue 33.30%Ultraviolet 38.50%Total insects caught 37
Figure 8: Figure 8: Percentage of insects attracted at
different colored light during night hoursin the rice field near the irrigation sitefrom January 10 to 13,2014.
Figure 9: Relative catch of insects using UV, Blue, Green and Red light trap in different localities. Site I (vegetable field), Site II
Red 12.80%
Green15.40%
Blue33.30%
UV 38.50%
Red14.80
% Green16.70
%
Blue33.30%
UV35.20
%
Red 8.60%Gree
n8.60
%
Blue22.20%
UV
60.60%
Site I
Site II
Site III
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(open space), Site III (rice field near irrigation site).
Orders Red Green Blue Ultraviolet Total
Coleoptera 5 6 8 17 45
Orthoptera 4 7 12 9 33
Hemiptera 5 7 12 16 32
Lepidoptera 2 2 4 8 15
Hymenopter
a- 2 - 4 6
Diptera 1 1 1 2 4
Mantodea - - 2 1 3
Dermaptera - - - 2 2
Blattodea - 1 - 1 2
Total 18 25 39 60 142
Figure 10: Total number of insects representing each order collected at red, green, blue and ultraviolet lights.
COL HEM ORT LEP DIP HYM MAN DER BLA0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
RedGreenBlueUltraviolet
Figure 11: Efficiency of different light sources (Red, Green, Blue, and Ultraviolet ) on different insect orders (COL= Coleoptera; HEM= Hemiptera; ORT= Orthoptera;; LEP= Lepidoptera; DIP= Diptera; HYM= Hymenoptera; MAN= Mantodea; DE= Dermaptera; and BLA= Blattodea).
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Site I Site II Site III0
2
4
6
8
10
12
14
16
18
20
Trend of Insect Collection
COL ORTHEMLEPHYMDIPMANDERBLA
Num
ber o
f ins
ects
Col
lect
ed
Figure 12: Number of collected insect in every order in different study sites.
Figure 13: Insecticide was use to kill insects and gather them by using a white blanket.
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Figure 14: Materials used in the study are killing jar, insecticide, container, hand lens, and forceps.
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Figure 15: Showing proper insect Curation techniques.
Figure 16: Insects caught using red light.
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22
Figure 17: Insects caught using green light.
Figure 18: Insects caught using blue light.
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Figure 19: Insects caught using ultraviolet light.
Figure 20: Insects collected in vegetable fields (Site I) from December 26 to 29, 2013.
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Figure 21: Insects collected in open space (Site II) Figure 22: Insects collected in rice fields near
from January 3 to 6, 2014. irrigation site (Site III) from January 10 to 13, 2013.