This document discusses common pests that affect farm crops. It begins by defining pests as living organisms that cause physical damage to plants, animals, and crops. Pests are then classified into three groups: biting and chewing insects, piercing and sucking insects, and boring insects. Examples of specific pests are then discussed in more detail, including the bean bug, pumpkin beetle, mealybug, aphids, and others. Each entry provides information on identification, damage caused, diet, and methods of control. The document also discusses plant diseases and their causes.

1. H.M.R.P. Perera
14/AG/023
Eg 1023
Common Pests in farmCommon Pests in farm

2. Who is a Pest?Who is a Pest?
• Pests are living organisms that cause physical
damage to man, animals and crops. In other
words, pests can described as any organism
capable of causing damage to crop plant.

3. Classification of insect pests.Classification of insect pests.
• These can be classified into various based
on their mode of feeding. These groups
of insect pests include:
1. Biting and chewing insects.
2. Piercing and sucking insects.
3. Boring insects.

4. Biting and Chewing insectsBiting and Chewing insects
These insects pests posses strong
mandible and maxillae which enable
them to bite and chew plant parts.

5. Piercing and Sucking Insects.Piercing and Sucking Insects.
• These insect pests possess strong mouth parts
called proboscis which enable them to pierce
through plants and suck liquid materials from plant
tissues.

6. Boring Insects.Boring Insects.
• These insects, including their larvae, are
capable of boring into plant parts and
destroy the tissues of the plants, fruits
or seeds.

7. Economic importance of InsectEconomic importance of Insect
Pests in Crop Production.Pests in Crop Production.
• Insects pests destroy crops in the field through their
biting, chewing, boring, sucking and defoliation
activities.
• They cause reduction in the viability of stored
produce.
• Site of injuries by insects may predispose crops to
disease attack.
• They increase the cost of production during the
course of controlling them.

8. Cont….Cont….
• They render vegetables and fruits unattractive and
unmarketable.
• Some carries or vectors of diseases.
• The profits of farmers are reduced.
• They reduce the quality of produce either in the
store or in the field.
• They generally reduce the yield of crops.
• They can also cause total death of crop plants.

9. Bean bugBean bug
Kingdom – Animalia
Phylum –
Arthropoda
Class – Insecta
Order - Hemiptera
Family - Alydinae
Genus - Riptortus
Riptortus pedestris

10. Cont…Cont…
• Identification.
 Brownish black and hemispherical.
 Nymphs resemble dark brown ants.

11. Cont..Cont..
• Damage.
Pods with black spots.
Shedding of green pods.
Poorly filled pods with shriveled grains inside.

12. Cont.Cont.
• Diet
 Fruit external feeding.
 Fruit lesions: black or brown.
 Seeds external feeding.
 Seeds lesions on seeds.

13. Cont.…Cont.…
• Control
 Intercropping.
 Dimethoate pesticide.

14. Pumpkin Beetle-Pumpkin Beetle- AulacophoraAulacophora
Kingdom – Animalia
Phylum –
Arthropoda
Class – Insecta
Order - Coleoptera
Family - Chrysomelidae
Genus - Aulacophora
Aulacopora nigripennis

15. Cont…Cont…
• Identification.
 Red oval beetles.
 About 8 mm long.
 On the leaves and flying between them.

16. Cont..Cont..
• Damage
 Fruit – external feeding.
 Inflorescence – external feeding.
 Leaves – external feeding.
 Roots – external feeding.
 Stems – external feeding.

17. Cont…Cont…
• Diet
 Adults feed on leaves, chewing large holes.
 Seedlings are particularly susceptible.
 The larvae damage roots and stems.

18. Cont…Cont…
• Control
 Resistant varieties.
 Avoid planting new crops next to those already
infested with the beetle.
 Use wood ash.
 Use plant derived products, such as neem.
 Alternatively, synthetic pyrethroids are likely to be
effective, but will also kill natural enemies.

19. MealybugMealybug
Kingdom – Animalia
Phylum –
Arthropoda
Class – Insecta
Order - Hemiptera
Family - Pseudococcidae
Pseudococcidae

20. Cont…Cont…
• Identification.
• Female adults are around 3mm long. Female adults
and nymphs are oval shaped and covered by a
white coating giving them a mealy appearance.
• They form colonies on shoots, stems, leave and
peanut kernels, developing into white masses.
• Males are small aphid like winged insects.

21. Cont…Cont…
• Damage.
 Yellowing, withering and falling leaves, prematurely
dropping fruit, and stunted plant growth may
indicate the presence of the mealy bug.

22. Cont…Cont…
• Diet
 In both the nymph and adult stages, sucking the
juices of the plant and feeding on any tender
younger growth.

23. Cont…Cont…
• Control
 Prune out light infestations or dab insects with a Q-
tip dipped in rubbing alcohol.
 Do not over water or over fertilize – mealybugs are
attracted to plants with high nitrogen levels and
soft growth.
 Commercially available beneficial insects such as
ladybugs, lacewing and the mealy bug destroyer
(Cryptolaemus montrouzieri) are important natural
predators of this pest.

24. Cont…Cont…
(Cryptolaemus montrouzieri) lacewing
These two pictures are copyrighted from the google.com

25. AphidsAphids
Kingdom – Animalia
Phylum –
Arthropoda
Class – Insecta
Order - Hemiptera
Family - Aphididae
Genus - Aphis
Aphis craccivora

26. Cont…Cont…
• Identification.
 Very small to rather large aphids.
 Adult viviparae may be winged or wingless.
 The body is broadly oval in shape, never very
elongate.

27. Cont…Cont…
• Damage.
 Cowpea aphids inject toxins into the plant while
feeding. They most likely reduce mungbean vigor
and yields.
 Aphid feeding also produces honeydew, which
grows sooty mould that reduces photosynthesis and
makes harvesting difficult.
 Cowpea aphid can cause damage as a Vector of
virus disease.

28. Cont…Cont…
• Diet
 Aphids passively feed on sap of phloem vessels in
plants, as do many of their fellow members of
Hemiptera such as scale insects and cicadas.

29. Cont…Cont…
• Control
 This pest is easily controlled with systemic
pesticides.
Pesticides that kill aphid predators should be
avoided. Parasitoids are often found in aphids.
Heavy rainfall can reduce populations significantly.

30. Horned leafhopperHorned leafhopper
Kingdom – Animalia
Phylum –
Arthropoda
Class – Insecta
Order - Hemiptera
Family - Cicadellidae
Idioscopus nitidulus

31. Cont…Cont…
• Identification.
 Adult leafhoppers are slender, wedge shaped, and
from1/8 to ¼ of an inch long.
 They are usually bright green, yellow or brown and
mottled.
 As their name implies, leafhoppers move rapidly –
they jump, fly or run backwards, forwards or
sideways when disturbed.

32. Cont…Cont…
• Damage.
 The insects cause leaves to appear stippled, pale or
brown and shoots may curl and die.
 Leafhoppers can secret honeydew which allows
sooty mold to grow.
 The bugs also transmit plant pathogens.

33. • Diet
 Leafhoppers feed on sap which robs plants of
essential nutrients.

34. Cont…Cont…
• Control
 Leafhoppers have numerous natural predators and
can be controlled with commercially available
beneficial insects such as ladybugs, lacewing, and
minute pirate bugs. Insecticidal soap also keeps
leafhopper populations under control.

35. Melon FlyMelon Fly
Kingdom – Animalia
Phylum –
Arthropoda
Class – Insecta
Order - Dipthera
Family - Tephritidae
Genus - Bactrocera
Bactrocera cucurbitae

36. Cont…Cont…
• Identification.
 The adult fly is 6 to 8 mm in length. Distinctive
character- istics of the adult are the wing pattern,
long third antennal segment, the dorsum of the
thorax reddish yellow with light yellow markings
and without black markings, and the head yellowish
with black spots.

37. Cont…Cont…
• Damage.
 it can attack flowers as well as fruit, and
additionally, will sometimes attack stem and root
tissue.
pumpkin and squash fieldshave been known to be
heavily attacked before fruit had even set, with eggs
being laid into unopened male and female flowers,
and larvae even developing successfully in the
taproots, stems and leaf stalk.

38. Cont…Cont…
• Diet
• Fruit internal feeding ,lesions: black or brown
• Inflorescence internal feeding
• Leaves internal feeding
• Roots internal feeding
• Stems internal feeding

39. Cont…Cont…
• Control
 One of the most effective control techniques against fruit flies in
general is to wrap fruit, either in newspaper, a paper bag, or in the case
of long/thin cucurbits, a polythene sleeve. This is a simple physical
barrier to oviposition, but it has to be applied well before the fruit is
attacked. Little data is available on the attack time for most fruits, but
few Bactrocera spp. attack prior to ripening.
 The use of bait sprays is both more economical and more
environmentally acceptable. A bait spray consists of a suitable
insecticide (e.g. malathion) mixed with a protein bait.

40. Eight-spotted ForesterEight-spotted Forester
Kingdom – Animalia
Phylum –
Arthropoda
Class – Insecta
Order - Lepidoptera
Family - Noctuidae
Genus - Alypia
Alypia octomaculata

41. Cont…Cont…
• Identification.
 Forewing black with two pale yellow spots and
inconspicuous metallic blue bands; hindwing black
with white spots in basal and median areas; body
black except for pale yellow tegulae and orange on
front and middle legs.

42. Cont…Cont…
• Damage.
 These caterpillars feed on plants in the grape family
including wild grape.

43. Cont…Cont…
• Diet
• Larvae feed on leaves of grape (Vitis spp.),
(Ampelopsis spp.), and Virginia Creeper
(Parthenocissus quinquefolia).
• Adults take nectar from flowers of herbaceous
plants, and fly during the day.

44. Cont…Cont…
• Control
 Control is not usually necessary, as low numbers of
these caterpillars do provide a food supply for
insectivorous birds.
Should control be desired, use of sprays containing
Bacillus thuringiensis or spinosad are low-toxicity
and have low impact on beneficial insects.
Pyrethroid insecticides provide fast control of heavy
infestations (rare).

45. Flea beetlesFlea beetles
Kingdom – Animalia
Phylum –
Arthropoda
Class – Insecta
Order - Coleoptera
Family - Chrysomelidae
Phyllotreta vittula

46. Cont…Cont…
• Identification.
 The adults are very small to moderately sized
Chrysomelidae.
 They are similar to other leaf beetles, but
characteristically have the hindleg femora greatly
enlarged.
 Many flea beetles are attractively colored; dark,
shiny and often metallic colors predominate.

47. Cont…Cont…
• Damage.
 The feeding scar will run parallel to the leaf veins and
sometimes zigzags across the vein into the next vein, giving
the feeding scar a jagged appearance.
 Most flea beetle damage is caused by adult flea beetles and
occurs as shallow pits and small rounded, irregular, holes in
the foliage, cotyledons, and stems of host plants.
 Flea beetles are a concern in corn production because they
can transmit Steward’s disease (bacterial wilt).

48. Cont…Cont…
• Diet
• Root feeding by larvae can cause economic damage
to corn.

49. Cont…Cont…
• Control
 Physical barriers such as row covers are safe and easy
methods of controlling flea beetles.
 can also use a layer of thick mulch around plants to limit the
insect’s transformation in the soil from larvae to adult.
 The most reliable method on how to get rid of flea beetles is
with an insecticidal dust. Naturally derived spinosad and
permethrin are two control agents that can provide some
assistance in eradicating the beetles.

50. Leaf miner attackLeaf miner attack
Kingdom – Animalia
Phylum –
Arthropoda
Class – Insecta
Order - Diptera
Family - Agromyzidae
Cerodontha denticornis

51. Cont…Cont…
• Identification.
 The easiest, most accurate way to identify leaf
miners is to look for their damage to host plants.
 They produce either large blotches or tunnels that
wander under the surface of the leaf.
 Leaf miner larvae are very flat.

52. Cont…Cont…
• Damage.
 Extremely large populations of leaf miners may
slow plant growth and cause infested leaves to drop
before the fall season.

53. Cont…Cont…
• Diet
 Leaf miners have a large number of preferred host plants.
 Among these are vegetables such as cabbage, lettuce,
tomatoes, peas and beans, plus flowering plants such as
begonias, dahlias, impatiens, marigolds and petunias. In
addition, leaf miners will infest trees or shrubs such as
evergreens, cottonwoods, elms, aspens, azaleas, boxwoods
and birch.

54. Cont…Cont…
• Control
 Covering plants with row covers to prevent the
adults from getting access to leaves and laying eggs.
Remove all leaves infested by larvae.
Keep plants well watered to help keep them healthy
and vigorous.

55. Pod borerPod borer
Kingdom – Animalia
Phylum –
Arthropoda
Class – Insecta
Order - Lepidoptera
Family - Crambidae
Genus - Maruca
Maruca vitrata

56. Cont…Cont…
• Identification.
 Stoutly built.
 Yellowish brown.
 A dark spec and

57. Cont…Cont…
• Damage.
 Bore holes on the buds, flower or pods
 Infested pods and flowers are webbed
together.

58. Cont…Cont…
• Diet
 The young larvae feed on the foliage for some time
and later bore into the pods and feed on the
developing grains.

59. Cont…Cont…
• Control
 Some parasitoid wasps have been shown to serve
as a biological control for Maruca vitrata. Parasitoid
families include Braconidae, Ichneumonidae
and Tachinidae.

60. LadyBird- PredetorLadyBird- Predetor
Kingdom – Animalia
Phylum –
Arthropoda
Class – Insecta
Order - Coleoptera
Family - Coccinellidae
Genus - Hippodamia
Hippodamia Convergens

61. Cont…Cont…
• All the ladybird beetles, with the
exception of the members of one
vegetation-eating genus, are
carnivorous. In both the adult and larval
stages they feed on insects harmful to
plants, such as aphids and scale insects.

62. Plant Diseases

63. What is Plant
Disease?
• The disruption of normal growth and metabolism in plants
leading to reduced viability and evendeath. Plant disease
s may begin with physical attack of the plant by pests suc
h as insects, slugs, mites, birds and otheranimals, some o
f which may be VECTORS of plant PATHOGENS
. Often, however, pathogens enter the plant via the wound
scaused by animal pests. Other pathogens, such as cerea
l rusts, are able to penetrate plant tissue on their own, ofte
n via leafstomata. Many plants produce special chemicals
called PHYTOALEXINS

64. Abiotic vs. Biotic Plant
Diseases
• Abiotic
• Temperature
• Moisture
• Nutrition
• Toxicity
• Cultura
Biotic
•Fungi
•Bacteria
•Viruses, viroids
•Nematodes

65. Damping off

66. Damping off….
• “ DAMPING OFF ’’, The single term used to describe
underground, soil line, or crown rots of seedlings due
to unknown causes.
• A soil-borne fungal disease that affects seeds and new
seedlings, damping off usually refers to the rotting of stem
and root tissues at and below the soil surface. In most
cases, infected plants will germinate and come up fine, but
within a few days they become water-soaked and mushy,
fall over at the base and die.

67. • Causal fungi….
 rhizoctonia
 fusarium
 phytophthora
 species of the soil
fungus pythium are
most often the
culprit.
Damping off….

68. • Damping off typically occurs when old seed is
planted in cold, wet soil and is further increased
by poor soil drainage. High humidity levels, rich
potting soils and planting too deeply will also
encourage its growth.
Damping off….

69. Treatments.
There is no cure for plants that already
have damping off.
Easily prevent the problem by providing
good air circulation.
The biological fungicide Mycostop may
also be used as a seed treatment to prevent
seed or soil-borne diseases.
Damping off….

70. Late Blight

71. • One of the most devastating
disease of potato and tomato
worldwide.
• Found on tomato and potato
plants.
• True to its name, the disease
occurs later in the growing
season with symptoms often
not appearing until after
blossom.
Late Blight…

72. • Causal fungi….
 Late blight is caused by the
fungus Phytophthora
infestans.
Late Blight…

73. • Late blight first appears on the lower, older
leaves as water-soaked, gray-green spots. As
the disease matures, these spots darken and
a white fungal growth forms on the undersides.
Eventually the entire plant will become
infected. Crops can be severely damaged.
• Unlike other fungal diseases, this plant
problem does not overwinter in the soil or on
garden trash.
Late Blight…

74. Late Blight…
Treatments.
Destroy all tomato and potato debris after
harvest.
Apply a copper based fungicide (2 oz/
gallon of water) every 7 days or less,
following heavy rain or when the amount of
disease is increasing rapidly. If possible, time
applications so that at least 12 hours of dry
weather follows application.

75. Rust

76. • There are more than 5,000 known
species of rust on plants.
• Common rust is a fungal disease that
attacks roses, hollyhocks, snapdragons,
daylilies, beans, tomatoes and lawns.
• It is most often found on mature plants
where symptoms appear primarily on the
surfaces of lower leaves.
Rust…

77. • Causal fungi….
 Puccinia striiformis -yellow or srip rust of
wheat ,barley and rye
Puccinia recondita -leafe of brown rust of
wheat and rye
Hemileia vastatrix -devastating cofee leaf
rust
Gymnosporangiumjuniperi-virginianae -cedar
apple rust
Uromyces appendiculatus -rust of legume
Rust…

78. • Early on, look for white, slightly raised spots on
the undersides of leaves and on the stems.
• After a short period of time, these spots become
covered with reddish-orange spore masses.
• Later, leaf postules may turn yellow-green and
eventually black. Severe infestations will deform
and yellow leaves and cause leaf drop.
Rust…

79. Rust…
Treatments.
Select rust-resistant plant varieties when available.
Pick off and destroy infected leaves and frequently rake under plants
to remove all fallen debris.
Water in the early morning hours — avoiding overhead sprinklers — to
give plants time to dry out during the day. Drip irrigation and
soaker hoses can be used to help keep leaves dry.
Apply copper sprays or sulfur powders to prevent infection of
susceptible plants. For best results, apply early or at first sign of disease.
Spray all plant parts thoroughly and repeat every 7-10 days up to the
day of harvest.

80. Downy mildew

81. • Downy mildew affects many
plants and appears as yellow
to white patches on the upper
surfaces of older leaves.
• This disease overwinters on
plant debris and in the soil.
Fungal spores can be carried
by insects, wind, rain or
garden tools.
Downy mildew…

82. • Causal fungi….
 Plasmopara viticola
Downy mildew…

83. • Appears as yellow to white patches on the
upper surfaces of older leaves.
• On the undersides, these areas are
covered with white to grayish, cotton-like
fungi.
• As the disease progresses leaves may
eventually turn crisp and brown and fall off
even though the plant has ample water.
Downy mildew…

84. Downy mildew…
Treatments.
The best way to prevent downy mildew is to avoid the
environmental conditions that favor the disease.
Prune or stake plants and remove any weeds to improve air
circulation.
Downy mildew is comparatively easy to control on most plants
when the foliage and fruit are kept protected by a copper spray.
Remove and destroy any plants with serious infection.

85. Vascular Wilt

86. • The wilting is caused by fungi.
• The slime they produce clogs
the water-transporting veins
of the plant.
• Both fungal vascular wilts can
kill the plants completely.
Vascular Wilt…

87. Vascular Wilt…
• Causal fungi….
 Fusarium
 Ophiostoma
 Ceratocystis

88. • Verticillium wilt often begins with wilting during the
hottest part of the day and recovering at night.
• The leaves may turn yellow, starting at the edges
and between the veins, and spreading inward.
• Usually both sides of the leaf are affected.
• Leaflets may also show a characteristic V-shaped
or fan-shaped yellowing, with the widest part of the
V on the leaf edge.
Vascular Wilt…

89. Vascular Wilt…
Treatments.
Remove affected solanaceous crops, such as potato, tomato, pepper
and eggplant, from the garden immediately to limit the spread of fungus
wilts. Additionally, strawberries and raspberries are susceptible to
Verticillium wilt. Prune affected branches of trees and shrubs, such as
fruit trees, maples and flowering or fruiting shrubs.
Destroy infected plant material by burning. Never add wilt-infected
materials to compost piles.
Seed bed sterilization

90. Leaf Spot

91. • Pathogen-caused leaf spot
diseases, particularly those of
stone fruit trees and such
vegetables as tomatoes,
peppers and lettuce.
Leaf Spot…

92. Leaf Spot…
• Causal bacteria….
 Pseudomonas
 Xanthomonas euvesicatoria
 Xanthomanas perforans

93. • Infected plants have brown or black water-soaked
spots on the foliage, sometimes with a yellow
halo, usually uniform in size.
• The spots enlarge and will run together under wet
conditions.
• Under dry conditions the spots have a speckled
appearance.
• As spots become more numerous, entire leaves
Leaf Spot…

94. Leaf Spot…
Treatments.
When selecting fruit trees, choose resistant varieties if possible.
Keep the soil under the tree clean and rake up fallen fruit.
Use a thick layer of mulch to cover the soil after you have raked and
cleaned it well. Mulch will reduce weeds and prevent the disease
pathogen from splashing back up onto the leaves.
Apply sulfur sprays or copper-based fungicides weekly at first sign of
disease to prevent its spread. These organic fungicides will not kill leaf
spot, but prevent the spores from germinating.

95. Tomato yellow leaf curl virus

96. Tomato yellow leaf curl virus
• TYLCV causes the most destructive disease of
tomato, and it can be found in tropical and
subtropical regions causing severe economic
losses.
• This virus is transmitted by an insect vector
from the family Aleyrodidae and
order Hemiptera, the whitefly Bemisia tabaci,
commonly known as the silverleaf whitefly or
the sweet potato whitefly.

97. Tomato yellow leaf curl virus…
• Causal virus….
 Tomato yellow leaf curl
virus (TYLCV) is a DNA virus
from the
genus Begomovirus and the
family Geminiviridae.

98.  Symptoms of TYLCV infection include severe stunting,
reduction of leaf size, upward cupping/curling of leaves,
chlorosis on leaves and flowers, and reduction of fruit
production.
 TYLCV is transmitted by the insect vector Bemisia
tabaci in a persistent-circulative non propagative manner.
 The virus can be efficiently transmitted during the adult
stages.
 In this plant-virus and vector system, females are more
effective than males transmitting the virus.
Tomato yellow leaf curl virus…

99. Tomato yellow leaf curl virus…
Treatments.
•Currently, the most effective treatments used to control the spread
of TYLCV are insecticides and resistant crop varieties.
•The effectiveness of insecticides is not optimal in tropical areas due
to whitefly resistance against the insecticides; therefore, insecticides
should be alternated or mixed to provide the most effective treatment
against virus transmission.
•Other methods to control the spread of TYLCV include planting
resistant/tolerant lines, crop rotation, and breeding for resistance of
TYLCV.

100. Mosaic Virus

101. • Affecting a wide variety of horticultural and vegetable
crops — roses, beans, tobacco, tomatoes, potatoes,
cucumbers and peppers.
• Mosaic virus overwinters on perennial weeds and is spread
by insects that feed on them. Aphids, leafhoppers,
whiteflies and cucumber beetles are common garden
pests that can transmit this disease.
• Soil, seed, starter pots and containers can be infected and
pass the virus to the plant.
• Cuttings or divisions from infected plants will also carry the
virus.
Mosaic Virus…

102. • Causal virus….
 Cucumber mosaic
virus (CMV) is a plant
pathogenic virus[1]
in the
family Bromoviridae.[2]
It is the
type member of the plant
virus[3]
genus, Cucumovirus.
Mosaic Virus…

103. • Yellow, white or green stripes/ streaks/ spots on
foliage.
• Wrinkled, curled or small leaves.
• Pronounced yellowing only of veins.
• Stunted growth and reduced yields.
• Infected fruit appears mottled and develops
raised “warty” areas.
Mosaic Virus…

104. Mosaic Virus…
Treatments.
• There are no cures for viral diseases such as
mosaic once a plant is infected.
•Spot treat with least-toxic, natural pest control
products, such as Safer Soap, Bon-
Neem and diatomaceous earth, to reduce the
number of disease carrying insects.

105. Blossom End Rot

106. • A serious disorder of tomato, pepper,
cucumber and eggplant, blossom end rot is
an environmental problem (not fungal) most
often caused by uneven watering or by
calcium deficiency.
• This common garden “disease” is often
brought on by rapid growth from too much
fertilizer, high salt levels or drought.
Blossom End Rot…

107. • Blossom end rot symptoms occur on both
green and ripe fruits and is identified by
water-soaked areas that gradually widen and
mature into sunken, brown, leathery spots on
the bottom end.
• In many cases, secondary pathogens, which
appear as a black, fuzzy-like growth, attack
the affected area and cause complete rotting
of the fruit. Blossom end rot will not spread
Blossom End Rot…

108. Blossom End Rot…
Treatments.
•Since this plant problem is physiological in
nature, fungicides will not work as a control
measure.
•Prevent problems by keeping soil evenly moist
and by foliar spraying plants with
a kelp or calcium solution.
•A layer of mulch (straw, compost, grass ) will
help conserve soil moisture during the hot, dry
days of July and August.