This document summarizes the effects of various insecticides on beneficial insects like bees and other pollinators. It discusses how neonicotinoids like imidacloprid and clothianidin are highly toxic to bees even at sublethal doses, impairing their homing ability and motor functions. Studies show neonicotinoids severely impact honeybee queen survival and reproduction. Other insecticides like synthetic pyrethroids and organophosphates also have adverse effects ranging from moderate to high toxicity on pollinators. The document advocates for safe use of chemicals and protecting habitats to prevent further pollinator population declines critical for food security.

1. Sher-e-Kashmir
University of Agricultural Sciences and Technology of
Kashmir
Wadura, Sopore-193201
Welcome to Doctoral Credit Seminar II
Name of Student Sheikh Aafreen Rehman
Registration No. 15/Ag(Entom.)19-D
Division Entomology
Seminar incharge Dr. Munazah Yaqoob
Date of seminar 25/08/2020

3. Insecticide
Insecticide is defined as any
substance or preparation intended
for the purpose of preventing,
destroying, repenting or mitigating
any insect.
Insecticide poisoning:
Term used when chemicals
intended to control insect
affect non-target organisms
such as humans, wildlife, plant
or bees.

4. Some astonishing facts
1,00,000 tones pesticides used in India
63 percent used in Agriculture
50-56 percent pesticides on cotton
Highest pesticide consumption in Andra Pradesh
Guntur = 77 kg/ha (Cotton)

5. Crop wise consumption of pesticides in India
State wise consumption of pesticides in India
Pesticide usage pattern in India

6. • Beneficial insects are any of a number of species
of insects that perform valued services like pollination
and pest control.
Crysoperla carnea
Cheilomenes
sexmaculata
Brumoides
suturalis
Trichogramma
Orius sp.
Encarsia sp. Bombus sp. Bombyx mori

7. Helpful insects
Beneficial insects
Productive insects
Silkworms/ honeybees
Pollinators Natural enemies
(Predator, Parasitoid,
Pathogen)
Honey bee Predatory shield bug Silkworm

8. Effects on beneficial insects
EFFECTS
DIRECT INDIRECT
Non lethal
Lethal

9. Non lethal Effects
Elimination of prey
• Contamination of floral parts
Consumption of active ingredient while
ingesting plant fluids
• Contamination of prey
Bashir et al. (2015)

10. Effect on
Natural
enemies
egg laying
feeding
mobility
Changed sex ratio
Developmental
impairment
egg
hatching
emergence
rate
Bashir et al. (2015)
Effect of insecticides on natural
enemies

11. Classification system for recognising adverse effects of pesticides on
beneficial and non-target arthropods as given by IOBC
Class Category % Mortality
Laboratory
studies
other
studies *
Class 1 Harmless
(low toxicity)
< 30% < 25%
Class 2 Slightly Harmful
(slight toxicity)
30-79% 25-50%
Class 3 Moderately
Harmful
(Medium toxicity)
80-98% 51-75%
Class 4 Harmful
(Highly toxic)
> 99%
> 75%
IOBC, 2013

12. Impact of common insecticides on beneficial insects
Insecticide
group* Persistence
Overall
ranking
Impact on beneficial insects
Predatory
beetles
Predatory
bugs
Parasitic
wasps Spiders Bees
FOLIAR-APPLIED
Bio-pesticides
Bt Short Low L L L L L
Helicoverpa NPV Short Low L L L L L
Metarhizium Short Low L L L L L
Petroleumspray oils Short Low L L L L L
L=Low toxicity= nil or low impact on Beneficials
M=Medium toxicity=activity is significantly reduced but beneficial populations are able to
recover in a week or so
H= High toxicity=high proportion of beneficial population killed and re
establishment will not occur for several weeks
(Pest management guide, 2013-2014)

13. Insecticide
group* Persistence
Overall
ranking
Impact on beneficial insects
Predatory
beetles
Predatory
bugs
Parasitic
wasps Spiders Bees
Organophosphates
Dimethoate
(low rate)
Short Moderate M M M L H
Dimethoate
(high rate)
Short High M M H M H
Methidathion Short High H H H H H
Indoxacarb Medium Low L L L L L
L=Low toxicity= nil or low impact on Beneficials
M=Medium toxicity=activity is significantly reduced but beneficial populations are able to
recover in a week or so
H= High toxicity=high proportion of beneficial population killed and re
establishment will not occur for several weeks
(Pest management guide, 2013-2014)

14. Insecticide
group*
Persisten
ce
Overall
ranking
Impact on beneficial insects
Predatory
beetles
Predatory
bugs
Parasitic
wasps Spiders Bees
Carbamates
Pirimicarb Short Low L L L L L
Thiodicarb Long High H M M M M
Methomyl Short High H M M M H
Avermectins
(emamectin
benzoate)
Medi
um
Moderat
e
L H M M H
Synthetic
pyrethroids
Long High H H H H H
Neonicotinoids Long High H H H H H
L=Low toxicity= nil or low impact on Beneficials
M=Medium toxicity=activity is significantly reduced but beneficial populations are able to
recover in a week or so
H= High toxicity=high proportion of beneficial population killed and re
establishment will not occur for several weeks
(Pest management guide, 2013-2014)

15. impact of insecticides on beneficial species in
vegetable crops
Trade name Active ingredient Concentration
Avatar indoxacarb 0.25 g/L
Belt flubendiamide 0.2 ml/L
Chess pymetrozine 0.4 g/L
Confidor 200SC imidacloprid 0.25 ml/L
Coragen chlorantraniliprole 0.2 ml/L
Cypermethrin cypermethrin 0.2 mL/L
Dipel Bacillus thuringiensis 1.0 g/L
Karate lambda-cyhalothrin 0.048 ml/L
Movento
spirotetramat 0.4 ml/L
Pirimor
Pirimicarb 2.0 g/L
Proclaim
Emamectin benzoate 0.5 g/L
Regent 200SC
fipronil 0.5 ml/L
Success
spinosad 0.4 ml/L
Vertimec abamectin 0.6 ml/L
Horne et al. (2013)

16. Beneficial species subjected to pesticide bioassays
Scientific name Common name Beneficial group
Coccinella transversalis Transverse ladybird Predatory beetle
Harmonia conformis Common-spotted ladybird Predatory beetle
Hippodamia variegata White-collared ladybird Predatory beetle
Dalotia sp. Predatory rove beetle Predatory beetle
Micromus tasmaniae Brown lacewing Predatory lacewing
Nabis kinbergii Damsel bug Predatory bug
Melangyna viridiceps Common Hoverfly Predatory fly
Phytoseiulus persimilis Persimilis Predatory mite
Neoseiulus cucumeris Cucumeris Predatory mite
Aphidius colemani General aphid parasite Parasitoid wasp
Diadegma semiclausum Plutella parasite Parasitoid wasp
Orgilus lepidus Potato tuber moth parasite Parasitoid wasp
Trichogramma pretiosum Trichogramma Parasitoid wasp
Horne et al. (2013)

17. Results
Product
Direct spray application
Insecticide
Avatar
(indoxacarb)
M
t
Mt Hc Hv Ct Nk Da Tp
Belt
(flubendiamide)
M
t
Mt Ct Nk Ds Tp
Chess
(pymetrozine)
M
t
Mt Hc Hv Ct Nk Mv Da Ac Ol Ds Tp
Confidor
(imidacloprid)
M
t
Mt Hc Hv Ct Nk Tp Da
Coragen
(chlorantraniliprole)
M
t
Mt Ct Nk Ds Tp
Cypermethrin M
t
Mt Ct Nk Pp
Dipel
(B. Thuringiensis)
M
t
Mt Ct Nk Hv Hc Pp Ol
Horne et al. (2013)

18. Product
Direct spray application
Insecticide
Karate
(lambda-cyhalothrin)
Mt Hv
Movento
(spirotetramat)
Mt Ct Nk Tp
Pirimor
(pirimicarb)
Mt Hc Hv Ct Nk Tp Da Mv Ol
Proclaim
(emamectin benzoate)
Mt Hc Hv Ct Nk Da Tp Mv Nc Pp
Regent 200SC (fipronil) Mt Hc Hv Nk Tp Da
Success
(spinosad)
Mt Hc Hv Ct Nk Mv Tp
Vertimec (abamectin) Mt Ct Nk Tp Pp
Horne et al. (2013)

19. Effect of Insecticides on Lady Bird Beetle (Coleoptera:
Coccinellidae) in Sunflower
• I
• Fenpropathrin, indoxacarb, imidacloprid, Spinosad,
Flubandiamide, Emamectin benzoate, chlorantraniliprol
Insecticides
• Effectiveness judged on the basis of level of lady bird beetle
population
Effectiveness
• Imidacloprid>flubendiamide>indoxacarb>chlorantraniliprole>
fenpropathrin >Emamectin benzoate and spinosad
Results
Dake et al.( 2017)

20. Effect of Insecticides on Lady Bird Beetle (Coleoptera:
Coccinellidae) in Sunflower
Dake et al.( 2017)

21. Lethal and behavioral effects of pesticides on the
insect predator Macrolophus pygmaeus
• Macrolophus pygmaeus predator of whiteflies, thrips, aphids, mites and eggs and
larvae of lepidopterous pests
• Insecticides used in study
INSECTICIDE FAMILY MODE OF ACTION
Chlorantraniliprole Anthranilic Diamide Ryanodine receptor modulator
Copper hydroxide Metalic hydroxide Fungal protein disruptor
Emamectin benzoate Avermectin Chloride channel activator
Indoxacarb Oxadiazine Sodium channel blocker
Metaflumizone Semicarbazone Sodium channel blocker
Spinosad Chloronicotinoid Nicotinic acetyl choline
receptor modulator
Thiachloprid Neonicotinoid Nicotinic acetyl choline
receptor agonist
(Martinou et al. (2014)

22. Treated eggs of Ephestia kuehniella and tomato leaves provided as
food to predator
Nymphs
Macrolophus pygmaeus
Treated tomato leaves
Treated Eggs of
Ephestia kauhniella
(Martinou et al. (2014)

23. Lethal effects on M. pygmaeus at 72
hours after treatment
(Martinou et al. (2014)

24. Behavioral effects on M. pygmaeus after 72
hours of treatment
Percentage of prey consumption
(Martinou et al. (2014)

25. POLLINATORS
• Wasps
• Bees
• Butterflies
• Moths
• Flies
• Bats
• Beetles
• Ants
• Birds
• Reptiles
And the list goes on, many different species take
interest in flowers!

26. Why pollinators are important
• For quality fruit and seed production
• More than 85 crops depend on pollinators
• 1 out of every 3 bites
of food can be attributed to pollinators
• 75% of pollination by honey bees

28. POLLINATORS ARE STRUGGLING
• Loss of habitat
• Lack of food (flowering plants)
• Use of pesticides (toxic chemicals)

29. How Pollinators are exposed to
Insecticides ?
• Direct contact
• Residue contact
• Contaminated nesting material
• Contaminated nesting areas

30. Effect of insecticides on
pollinators
• On Navigation
• Communication and learning
• Interference with feeding behaviour
• Flower and nest recognition
• Impaired foraging and immune suppression
• Besides these effects on pollinator population
decline, one of the major effect is immune
inhibition by neurotoxic insecticides particularly
Neonicotinoids. (Basu et al. (2015)

31. Neonicotinoids
• Most widely used insecticides in the world
• Contribute 24% of global market for insecticides
• Systemic in nature
• Persistent
• Cause stimulation at low doses

32. Mode of action
They are nicotinic acetylcholine receptor agonists
They bind strongly to nicotine acetylcholine
receptors (nAChRs) in the central nervous system
of insects , causing nervous stimulation at low
concentrations, but receptor blockage, paralysis
and death at higher concentrations
Neonicotinoids bind more strongly to insect
nAChRs than those of vertebrates, so they are
selectively more toxic to insects

34. Neonicotinoid exposure to bees

35. Synthetic pyrethroids
• Pyrethroids are synthetic analogues of pyrethrins.
• Contact insecticides

36. Toxicity classification scale for bees
Toxicity rating LD50
Highly toxic (H) <2µg
Moderately toxic (M) 2-10.99µg
Slightly toxic (S) 11-100µg
Practically non-toxic (N) >100µg

37. • Cypermethrin and permethrin were highly toxic insecticides against foraging
workers of A. cerana indica. Methyl demeton and phosphamidon were
moderately toxic while endosulfan was found to be least toxic with (Reddy,
1997)
• On the basis of LD50, cypermethrin, imidacloprid, lambda cyhalothrin and
spinosad were found to be highly toxic (0.001-1.99 μg/bee), endosulfan as
moderatley toxic (LD50 2.0-10.0 μg/bee) and azadirachtin, Bacillus thuringiensis
subsp. kurstaki, benzoylphenyl urea, spiromesifen as relatively non-toxic with
LD 50 > 11.0 μg/bee (Choudhary, 2007)
• Karnatak and Thorat (2006) monitored the effects of some common insecticides
and reported the order of toxicity as follows:
imidacloprid > quinalphos > oxydemeton-methyl > endosulfan
Research on safe use of insecticides on bees

38. Reduction in homing flights in the honey bee Apis mellifera
after a sublethal dose of neonicotinoid insecticides
• Four insecticides used in study
• Sampled 100 Bees
Treatment INSECTICIDE NAME GROUP
T1 Clothianidin Neonicotinoid
T2 Dinotefuran Neonicotinoid
T3 Etofenprox Synthetic pyrethroid
T4 fenitrothion Organophosphate
100
20 20 20 20
20
½ LD 5O, ¼ LD50, 1/10 LD 50
T1 T3
T2 T4 T5
(Matsumoto et al. (2013)

39. RESULTS
Percentage
of
Succesful
homing
flights
½ LD 50 ¼ LD 50 1/10 LD 50
(Matsumoto et al. (2013)

40. A common neonicotinoid, thaimethoxam impairs
honey bee activity, motor functions, and
movement to light
This study was
conducted in University
of Californai San Diego
(Tosi et al. (2017)

41.  This study presents first evidence that thaimethoxam
exposure at field realistic sub-lethal levels can significantly
alter forager movement to light
 They used vertical arena illuminated from top to assess
forager locomotion and movement to light .
 Each forager was tested inside arena twice 30min and 60
min after treatment .
 During each test bee behaviour was recorded for three
minutes.
 Over three minute observation 11 behavioural parameters
were recorded related to bee activity, motor function and
movement to light

44. Neonicotinoid pesticides severely
affect honey bee queens
Geoffrey et al. (2015)

45. Queen survival after 4 weeks
(percent honey bees that were alive after 4 weeks)
Geoffrey et al. (2015)

46. ( b.) Percent of honey bee queens that were alive and had produced diploid
offspring by the end of experiment (=successful) Geoffrey et al. (2015)

47. Queen oviposition and survival after 4 weeks
( a.) percent of honey bee queens that oviposited (laid
worker eggs)
Geoffrey et al. (2015)

48. Effect of insecticides on
sericulture
• Sericulture is an integral part of the rural economy in an
agrarian country like India
• India is the second largest silk producing country next only
to China
• Mulberry is the sole food of silkworm, Bombyx mori L. and
is infested by several pests
• The insecticides applied for the management of mulberry
pests have greater impact on silkworm.

49. Effects
• Effects Mortality
Loss of cocoon yield
Pronounced effect
Insect Growth regulators (IGRs)
IGRs are usually synthetic versions of naturally occurring hormones
and they act by maintaining high levels of juvenile hormone in the
insect.
Non spinning syndrome

50. Reasons for non spinning syndrome
Selected 14 cocoon breeders
Analysed cocoon production
Hemolymph samples taken from the
larvae
Doses of Hydropene in haemolymph
Suman et al.( 2017)

51. In the farms, where high level of hydropene was found in larvae,
following symptoms appeared
Unpupated larvae
Malformed cocoon
The matured larvae in the last
instar, but they died no making
cocoon.
Suman et al.( 2017)

52. Pesticide management to reduce loss of beneficial
insects
1. Use pesticides only when needed
• Heavy infestation
2. Don’t use pesticides in Bloom
3. Use of safest formulation
• Granular formulations are safest
• Dusts Harmful than Sprays
• Adding solvent make the sprays safest

53. 4. Method of pesticide application
Pesticide management to reduce loss of beneficial
insects
Ground application safer
than aerail application
Don’t apply pesticide when pollinators flying
Repellants may be used to discourage beneficials from
foraging on the treated crop
5. Timing of pesticide application
combined application is often safer as well as cheaper than the individual application
Morning or evening spray

54. Conclusion
• Consideration of pesticide impacts on beneficial insects in crops should
be part of decision making for all spray applications.
• Application of insecticides should be considered as a back-up to other
pest control strategies such as biological and cultural controls.
• Selective insecticides should be chosen
• Growers and advisors need better understanding of the beneficial
species present in their crops and to achieve this requires monitoring of
crops and education in insect identification.
• The online pesticide charts and information on safety of insecticides need to
be made available to the public