Trap crops in Pest management

Managing pests without chemical pesticides requires innovative practices. One such innovative practice is growing trap crops. Trap crop is a crop which attracts pests more than the main crop. Pests prefer trap crops for feed or oviposition.   Pests are either prevented from reaching the main crop or concentrated in certain parts of the field away from the main crop. The principle of trap crop relies on pest preference for certain crops or stages of crop growth.  Two preliminary techniques used in trap crops are:

A.      Selection of more preferred species

B.      Planting of the same crop before the main crop so that preferred stage of the development will arrive earlier than the main crop     

Advantage of trap crops:

1.       Lessens the usage of pesticides

2.       Preserves natural enemies

3.       Enhance biodiversity

4.       Increase productivity

Types of trap crops: Trap crops can be classified based on spatial distribution and characteristics of trap crops.

Based on characteristics of trap crop:

A.      Conventional trap crop: It is most common practice. These plants are preferred fro oviposition Growing of trap crops next to the main crops. Ex: Castor and marigold in Ground nut crop

B.      Dead end Trap cropping: Trap crops which are highly attractive to insects but they or their offsprings can’t survive.  Ex: Indian mustered for Cabbage diamond back moth. Sun hemp for bean pod borer 

C.      Genetically modified trap cropping: Crops are genetically modified to attract pests. Ex. Genetically engineered Potato for colerado Potato beetle

Based on spatial distribution:

A.      Perimeter trap cropping: Growing trap crops around the main crop.

B.      Sequential trap cropping: Growing trap crops earlier or simultaneously than the main crop to attract the pest. Ex. Indian mustard as a trap crop for diamnon back month in Cabbage

C.      Multiple trap cropping: Planting of several species simultaneously as trap crops for attracting pests   

D.      Push – Pull trap cropping: Growing combination of trap crop and repellent crops ex. Marigold and Onion in Chillies

Examples of trap crops:

S.No	Name of the main crop	Trap crop	Pest
1	Cotton	Marigold	Heliothis
		Bhendi	Pod borers
2	Ground nut	Cow pea	Leaf folder
		Castor	Tobacco caterpillar
3	Red gram	Soya bean/ Green gram	Thrips
4	Sun flower	Mari gold	Heliothis
		Castor	Tobbacco catre pillar
5	Bengal gram	Mari gold	Heliothis
6	Cabbage	Indian Mustard	Diamond back moth
7	Cotton	Alfa alfa	Laygus bug
8	Garlic	Basil and Mari gold	Trips
9	Carrot	Onion and garlic	Carrot root fly
10	Cabbage	raddish	Flee beetle

Tips for successful trap cropping:

A.      Select a trap crop that is more attractive to pest than the main crop

B.      Monitor trap crops regularly

C.      Immediately destroy the eggs that are found on the trap crop