Entomology One Liner
1. “An Insect or any other living organism whose population increases to such an extent to cause economic losses to crops or a nuisance and health hazard to man and his livestock” is called Pest.
2. Entomology is derived from Greek words: Entomo meaning ‘Insect’ and Logos meaning ‘Discourse’.
3. Phylum Arthropoda (from Greek word ‘Anthros’ meaning ‘segmented’ and ‘podus’ meaning ‘leg’) is the largest group.
4. Insects are 97% of total population of Arthropoda.
5. Economic Threshold Level (ETL) is the pest density at which control measures should be applied or which needs control measure.
6. Economic Injury Level (EIL) is the lowest population density that will cause economic damages or produces incremental damage equal to the cost of preventing damage.
7. Mites, Ticks, Red spider etc. comes under class ‘Arachnida’. Here head and thorax are fused while abdomen is distinct. It has no antenna.
8. Ticks and Mites have piercing type mouth parts.
9. Incomplete/Direct/Hemi-Metamorphosis occurs in three stages: Egg————Nymph————Adult.
10. Incomplete Metamorphosis occurs in orders such as, Orthoptera (Grasshopper, cockroach, Locust), Thysanoptera (Thrips), Isoptera (Termites), Heteroptera (True bugs) and Homoptera (Aphids, leaf hoppers).
11. Complete/Indirect/Holo-Metamorphosis occurs in four phases: Egg———Larva———Pupa(cocoon)———-Adult.
12. Complete Metamorphosis occurs in orders such as, Coleoptera (beetles, weevils), Lepidoptera (moths, butterfly, silkworm), Diptera (flies), Hymenoptera (saw fly, ants, bees, wasps).
13. Mostly insects from order Hymenoptera are used as predators. Most damaging order is coleoptera.
14. Radial changes in morphology during development is called Metamorphosis.
15. Mouth parts of insect comprises of (1) Maxilla- Cut food materials, (2) Mandible– crushes the food, (3) Labium– Acts as lower lip, (4) Labrum– Acts like upper lip (5) Hypopharynx– works like tongue.
16. Piercing & Sucking type of insects are Mosquito, Leafhoppers, Aphids, bugs etc. Such insects are controlled by Systemic or Contact poison.
17. Chewing/Biting and Cutting type insects are Grasshoppers, locust, cricket, beetles, weevils and All larva. Such type of insects are controlled by stomach poison.
18. Rasping & Lapping type or Chewing & Lapping type mouth parts are found in- Honeybee.
19. Housefly has sponging type mouth.
20. Larva is of four types namely, (1) Nymph (2) Caterpillar (3) Grub (4) Maggot.
21. Larva of order Lepidoptera is called Caterpillar, Grub in Coleoptera, Maggot in Diptera and Nymph in Hemiptera order.
22. Except Mustard sawfly all other insects of order Hymenoptera are beneficial and used as biological control agents.
23. Systemic poison affects metabolism of sucking insect pests hence are used to control sucking pests. Ex: Dicrotophos, Rogor, Metasystox & systox, Monochrotophos, Phosphomidon, Aldicarb, Carbofuran, Thimet and Thionazin.
24. Stomach poison acts on digestive system of insects when ingested and are used to control chewing type insects. Ex: Heptachlor, Endosulfan, Chlordane, DDT, Aldrin, Quinolphos.
25. Contact poison brings death of insects when comes in contact through penetrating into body through vulnerable sites like trachea, sutures.
26. Chlorinated insecticides are generally both stomach and contact poisons.
27. Fumigants are chemicals enters in gaseous form through transpiratory system and kills the pests hence used to control all type of insects irrespective of its feeding habits. Ex: Aluminium Phosphide.
28. Bhopal gas tragedy was occurred on 3 December 1984 in Union carbide of India at Bhopal. Here Methyl Isocyanate was manufactured for production of Carbaryl.
29. Trade name of Aluminium phosphide is Celphos.
30. Zinc phosphide is a Rat poison.
31. Inorganic compounds are stomach poison and used to control chewing mouth insects.
32. Lime Sulphur was first used as fungicide in 1852 to control San Jose scale by Grison.
33. Pyrethrins are powerful contact insecticides which rapidly paralyses the housefly. This characteristic action is called as “knock down” effect.
34. Insecticide Vapacide is prepared from Neem cake.
35. Sabadilla is an alkaloid derived from seeds of tropical Lilly (schoenocaulon officinale), family-Liliaceae.
36. DDT was 1st synthesized by Othmar Zeidler in 1874 but its insecticidal property was 1st discovered by Paul Herman Muller in 1939.
37. Dicofol (Kelthane) is effective acaricide used to control mites.
38. Van Der Linden discovered four isomers of BHC (Benzene Hexachloride) in 1912.
39. DDT is mixture of two isomers (1) pp’-DDT (2) op’ -DDT.
40. The insecticidal property of organo-phosphates was firstly discovered by Gerhard Schrader in 1939.
41. Trade name of DINOCAP is Karathane.
42. General dose of systemic pesticides: @0.02-0.05% a.i. for spray.
43. General dose of Contact pesticides: @0.05-0.07% or 1% for spray, Granular systemic insecticides @1-2 kg a.i/ha for soil application.
44. General dose of fungicides @2g/l depending on chemical used, pest species and season of application.
45. The most extensively used fumigant is HCN (Hydrogen cyanide). HCN was firstly used to control cotton cushion scale (Icerya perchasi) in 1886 by D.W Coquillet.
46. Hydrogen Phosphide is widely used in fumigating grains, flour and cereals in godowns.
47. The maximum used of pesticides in India is on cotton, around more than 50%.
48. 1st generation of Insecticides: Initial stage of the use of chlorinated and organophosphates.
49. 2nd generation of Insecticides: It is known for modern synthetic insecticides, having less toxicity and more selective effect on target organism.
50. 3rd generation: Era of target specific and non-toxic insecticides, e.g. use of juvenile hormone, repellents, sex attractants etc.
51. 4th generation of insecticides: Use of anti-hormonal (precocene) insecticides.
52. The process of getting mixture by adding inert materials (Additives) to the pure and technical form is known as formulation. Toxicant is required to be formulated.
53. Dust additives may be organic compounds like walnut flour, soyabean shell, wood bark; or inorganic compounds like pulverized minerals, lime, gypsum, talc or clay.
54. Spray additives includes solvent (kerosine oil, petroleum diesel, xylene); Wetting agents and Emulsifier (sodium oleate, amines, sodium lauryl sulphate).
55. Wetting agents are required to convert a water insoluble into a soluble or partly soluble one.
56. Emulsifier is required to prevent a solvent dissolved toxicant from precipitating out.
57. Emulsifiable concentrate (EC)= Toxicant + Solvent + Emulsifier + Water.
58. Calcium caseinate, soybean flour, sulphated alcohols are used as Spreader/Deflocculator which improve wetting through spreading property.
59. Gelatin, Resins, Glue, Starch, Vegetable oils are called sticker which prevent pesticides from washing off by rain or dew.
60. Stabiliser are additives required to retard rapid decomposition of unstable organic pesticides.
61. Softener spray additives (sulphur, zinc sulphate, lime casein) reduces the phytotoxicity of pesticides.
62. Masker or Deodorants masks the unpleasant odours, e.g. cedar oil, pine oil and scents.
63. Formulation of pesticides may be solid formulation (Dust, Granules) or Liquid formulation (concentrated liquid, solution concentrate, EC, Suspension, Foam, Mist, Fog, Aerosols, WDP/WP, WSP/SP) or Gaseous formulation.
64. Water dispersible powder/ Wettable powder (WDP/WP) is the powder formulation which yields rather stable suspensuin when diluted with water. Here a.i. ranges to 15-95% but common a.i. is 25-50%.
65. Water soluble powder (WSP/SP) contains high concentration of active ingredients hence easy to store and transport. WP is a powder formulation readily soluble in water.
66. Particle size of Smoke is 0.001-0.1 micron.
67. Droplet or particle size of Aerosols: 0.1-50 micron, Fog: 1-50 micron, Mist: 50-150 micron.
68. Spray volume of High volume spray: >400 lit/ha, Low volume spray: 5-400 lit/ha, Ultra-low volume spray: <5 lit/ha.
69. Bacillus thuringiensis is microbial (Bacterial) insecticides.
70. Dimethoate, Monocrotophos and Phosphomidon are organic systemic insecticides whereas, Malathion, Parathion are organic contact insecticides.
71. Soil sterilant are Carbon disulphide, formaldehyde, chloropicrin whereas, Ethylene dibromide has nematocidal property.
72. Sprout Inhibitors and Desuckering agents: Chlorpropham, Propham.
73. Fruit setting, Ripening, flowering agents: Ethephor, Dimas, Glyphosine, Naphthaleneacetic acid.
74. Growth promoters: Gibberellic acid.
75. Growth Inhibitors: chlormequat.
76. Pesticides banned for manufacture and import in India: BHC, Aldicarb, Aldrin, Nitrofen, Calcium cyanide, Endrin, Chlordane, PMA etc.
77. Other than Blower, Duster contains a container called Hopper.
78. Sprayers are the most commonly used in the pesticides application.
79. The movement of pesticides in different level of food chain where they become more and more concentrated and deposited in human body (top consumer) where their concentration reaches to highest level, such increment in the concentration of pesticides is known as Bio-magnification.
80. The term IPM was first coined by Barlett in 1956.
81. BIPM (Bio-intensive Integrated Pest Management) is new name of Integrated Pest Management (IPM) wherein, pest population and population of concerned natural enemies are so coordinated that the pest population can not cross the line of economic injury.
82. E.F. Knipling developed sterile insect technique and he was thus propounded of the concept of genetic control if insect-pest.
83. First insect scientifically employed for any biological control programme was: Vadalia beetle (Rodolia cardinalis).
84. The stability of pest population over a long time is called Homeostasis.
85. When an insect is itself a parasite then it is called Parasitoid.
86. A parasite is an organism that lives on or in a living host organism and gets its food from there.
87. Saprophytes obtain their nutrition from dead decaying organic matters.
88. Predators are those who kills other organism for their food.
89. Father of microbial control: Felix d’ Herelle.
90. The term “microbial control” was coined in 1949 by Steinhaus.
91. The method of exclusion of pests, enforced through certain legal measures is known as Quarantine.
92. Potato tuber moth or tobacco splitworm (Phtthorimaea operculella) was introduced from Italy to India in 1900.
93. Varietal resistance against the insect pest is of four categories namely Tolerance, Avoidance, Non-preference/Antixenosis and Antibiosis.
94. In case of tolerance, the host plant is attacked by pests but there is little or no loss in biomass production or yield.
95. The lethal or harmful effect of plant on the life of insect pest is known as Antibiosis. The morphological, physiological or biochemical features of the host plant either individually or in combination may attribute to Antibiosis.
96. Vertical Resistance/Race specific/Pathotype specific is effective against only one or some specific pathotypes and is determined by oligoene.
97. Horizontal resistance/Field Resistance/Race or Pathotype non-specific is effective against all the known pathotypes and determined by polygenes. Here reproduction rate= 1 > r > 0.
98. The word ‘pheromone’ was coined by Karlson and Butenandt in 1959.
99. Pheromones are chemicals substance produced by an organism exogenously which influence the behaviour physiology of other member of its own species.
100. Juvenile hormone, chitin inhibitors, Altoid, Kinoprene, Altozar, Azadirachtin are examples of Insect Growth Regulators (IGR).
See also…
PLANT PATHOLOGY- AN OVERVIEW
CLASSIFICATION OF PLANT DISEASES