10. TRAPS IN PEST MANAGEMENT

TRAPS IN PEST MANAGEMENT

Attract &  annihilate method is the most widely used behavioral manipulation approach in pest management and the strategy of the method is to attract the pests to a site as many of them as possible, and be trapped and killed.

S.No.	Attractant	Device (traps) developed
1	Visual stimuli (light, colour)	Light trap, Sticky trap
2	Olfactory stimuli & phagostimulatory (Volatile chemicals, food smell)	Poison bait trap, Pheromone trap

                       

1.      Light traps       

Light trap is a device used at night in the field to collect moths and other flying insects such as Armyworm, Bugs, Cutworm, Flies, Gnats, Leafhoppers, Planthoppers, bugs, chafer beetles, Rice leaf folder, Rice Stem borer, Cotton boll worm, Red hairy caterpillar and other nocturnal insects.

Many models of light traps have been designed and used in the pest management programmes. The oldest are Robinson and New Jersey models.

v  Light trap can be fabricated from a funnel, a round gallon can and a light.

v  Light source may be oil lamp or electric bulb.

v  Kerosenated water or soapy water or insecticide is used as killing agent

v  Install the light trap near or within the field and 2-3 feet above the crop level.

v  Insects that fly towards the light bulb fall down the funnel and are trapped in the can. The spout of the funnel should be large enough to let the insects drop through it easily.

v  Collect the trapped insects daily and dispose them properly.

 

Models of light traps

a) Simple Bamboo light trap

Materials needed to fabricate simple bamboo light trap are,

1.      Bamboo or wooden poles

2.      String or rope

3.      Nails

4.      electric bulb

5.      Shallow basin with kerosenated water

Bamboo stacks are joined in a fashion to hold a bulb.  A shallow bamboo basin, lined with thick polythene sheet is placed under the light source. kerosenated water or soapy water is filled in the bamboo basin. Then this arrangement is kept in the field at a height over a stand made up of bamboo poles. The electric bulb may be 60 /100W capacity. 200W lamp is used for attracting rice earhead bugs.

  

     b) Robinson light trap

"Robinson" light trap was originally published in 1950s. 125W Mercury – Vapour bulb is used in the Robinson light trap.  Bulb is fixed at the top of a galvanized iron funnel which terminating in a collecting jar containing killing agent.

   

    c) New Jersey light trap

        The New Jersey mosquito light trap is widely used in obtaining data on the density and species composition of mosquito populations. It is powered by a 110 volts AC.

   

   d) Ultra violet trap (Black light trap)

Black lights, or ultraviolet lights, are more attractive to insects than lights of other lights. UV bulbs of various capacity are used in this trap. For example 4W germicidal bulb (253 nanometer UV rays) is used to attract storage pests like Lesser grain borer, Flour beetle, Saw toothed beetle in godown and is placed 1.5 m above the surface level.

 

   e) Zappers or Electric fly killers

In this traps 115 V electric current is flowing through an iron grid of the trap. The flying insects attracted by UV light are killed by 'electrocution drowning' (mild shock). It is used in food industry to attract houseflies.                                        

2. STICKY TRAPs

A metal plate or a container or a square pieces of cardboard or a hard plastic painted with suitable colour and smeared with sticky materials like white grease or castor oil or gel or glue is placed throughout the growing area among the plants, to attract insect pests is called as a sticky trap.

Example of sticky traps
Yellow sticky traps - Aphids, whiteflies, jassids, gall flies, Cabbage root maggot, Carrot rust fly, Cucumber beetle, Fungus gnat, Onion fly
Sticky red sphere - Apple maggot

1. Green sticky sphere - walnut husk fly
2. White sticky trap - Flea beetles and tarnished plant bugs
3. Yellow water pan trap – Brown plant hopper, White backed plant hopper
4. Square green glue trap - Groundnut leaf miner
5. Blue sticky trap – Thrips

8.      Trapper Glue Boards  - Rats

Place Trapper Glue Boards in areas where rodents will most likely cross over them as they move from hiding places to feeding areas.

 3. POISON BAIT TRAPS

Food material or food smelling chemical mixed with insecticide which is used to attract insects and rats are known as poison bait. The device used to keep poison bait and hold or trap the attracted insects or rats are called poison bait trap. 

Example of poison baits

1. Fish meal bait

ü  25 g of moist fish meal + 1 ml Nuvan / trap

ü  To attract Sorghum shoot fly, Chow-chow fruit fly

ü  Fix 30-50 cm above the crop level                    

2. Poison balls

ü  Rice bran (12.5 kg) + Jaggery (1.25 kg) + carbaryl (1.25 kg) + water (7.5 Lit)/ac

ü  To attract Tobacco caterpillar

ü  Balls be placed along the rows of crops

3. Food smelling Chemical baits

a) Methyl eugenol, Anisyl acetate - Fruit flies Dacus dorsalis

ü  A cotton wad charged with 0.4 ml methyl eugenol and 1 ml of dichlorvos attracts fruit flies from a distance of 800 m.

ü  Replenish the chemical at fortnightly intervals.

ü  Maintain a distance of 50 m between two traps

ü  Yellow or transparent containers are used as traps.

b) Protein hydrolysate bait and 1 ml of dichlorvos - Walnut husk fly          

c) Geraniol and Eugenol (1:1) and 1 ml of dichlorvos - Japanese beetle

d) Fermenting sugars, Molasses and 1 ml of dichlorvos - Coconut Rhinoceros beetle,

e) Toddy and 1 ml of dichlorvos - Fruit sucking moth

       4.  Rat baits

Zinc phosphide 1:49 parts of popped corn/ rice/ dry fish (Pre-baiting for 2 days)

Warfarin 1 parts: 19 parts of bait and oil

Bromadiolone 0.25%  20 g + 20 ml oil+ 20 g powdered sugar +1 kg of cereal flour

Bromadiolone 0.005%  + broken cereals + jaggery+ Parffin wax     

Bait stations:

Bait stations are the containers for placing poison bait and it protects the bait from rain, sunlight and other non target animals.

            Eg.       1. Tin container with puncturings (holes) – to keep Fishmeal bait

2. Mud pot - To keep molasses, Toddy and fermenting sugars bait  

3. Box type (rectangular box with 7.5 cm dia holes) -  to keep rat baits 

4. Bamboo type (bamboo sticks one side closed with tin sheets) - to keep rat baits 

BAIT TRAPS:

Eg.       Tanjore bow trap: A trap used to kill the rats attracted towards the food bait. 20-25 traps/acre are recommended.

 4. PHEROMONE TRAPS

 Sex Pheromones: Adult insects that are ready for mating emit species-specific chemical odours (sex pheromone) to attract opposite sex.

Aggregation pheromones: Insects also produce chemicals to call others to a location. These are called aggregation pheromones and can be effectively used to trap both males and females since both sexes respond to the chemical signal.

This method of utilising pheromones as tools for their destruction, was first introduced in India by PCI. Lab-synthesised pheromones are specially packed and supplied as lures or rubber septa, to be used along with suitable traps to deceive, attract and trap insects.

Due to mass trapping of males using sex pheromones the majorities of females present in cropped fields remain unmated and lay infertile eggs as a result of mass trapping of males.

Models of pheromone traps

Funnel type

v  Funnel, polythene sleeve and circular top are the parts of Funnel type

v  Funnel is fitted with a circular top & lure inserted in the middle slot

v  Insecticide soaked cotton swab placed in the polythene sleeve kills attracted insects

Delta type

v  Triangular paper bowl with lure placed inside

v  Attracted insects struck to the gummy substance smeared inside the trap

    

Canister type

v  Container like trap