Role of Insect Trap Crops;Different methods of Trap Cropping; Limitations in trap Cropping

 

A trap crop may be a crop that is grown as a target crop next to the main crop or a cash crop that is more appealing to certain pests. Trap cropping is a form of cultural control within IPM (Integrated Pest Management) and an essential step towards sustainable agriculture practices. When used correctly trap cropping can be a sustainable and beneficial form of pest control. 

Sunflowers are attractive to stink bugs and other sucking pests with belong to Hemiptera species and reduce the noticeable damage to solanaceous crops. There are various types of trap cropping, that are specified by the type of plants, their time of planting, and the place of plants where they are grown within the field.

Different methods of trap cropping: 

1. Conventional Trap Cropping:

                               

An established and effective plan is planting the sunflowers around or within the tomato crop(Cash Crop). Sunflowers are more attractive to target pests as either a food source or for reproduction. In this example of Sunflower and Tomato, we are providing the more desirable crop to caution the desired pest away from our cash crop or the main crop.  

2. Dead-end Trap Cropping:

                              

Plants are appealing to a target pest but on which their progeny will not survive. Dead-end trap cropping serves as a pitch and prevents the movement of the target pests toward the cash crop or main crop later in the season. Dead-end trap crops are planted in boundaries or edges of the field where they easily interrupt target insect pests.  

An example of Dead trap cropping includes the use of yellow rocket mustard plants to appeal to diamondback moths to lay their eggs on them instead of cabbage (Cash crop). After hatching the larvae of the diamondback moth will fail to establish and survive on the yellow rocket mustards. 

3. Genetically Engineered Trap Cropping:

                               

Plants can be genetically engineered and can be used as a trap crop. Blockage of insect vector diseases is one of the examples where the trap crop is capable of bearing a certain virus but its insect vector cannot obtain it from the plant.

For example, The trap crop helps to lower the insect vector pathogen as opposed to the insect itself. Genetically modified potatoes that exhibit the protein from  Bacillus thuringiensis will be toxic to the Colorado potato beetle. When larvae of Colorado potato beetle larvae costume the foliage they will die. Farmers can choose to plant GMO potatoes at the edges and grow non-GMO potatoes as the main crop in between them. 

4. Perimeter Trap Cropping:

                               

In Perimeter trap cropping the trap crops are planted around the boundaries or the border of the main crop. A good example of perimeter trap cropping includes the use of Hot Cherry peppers to attract the Pepper maggots away from the desired Bell Pepper ( Cash Crop)

5. Sequential Trap Cropping:

                             

Traps crops that are grown either earlier or later than the main crop to increase the attractiveness to the insect pests during certain times of the season. An excellent example of it is growing the early season potatoes will be longer and more appealing to the Colorado potato beetle protecting the younger and unmatured potatoes.

6. Multiple Trap Cropping:

                             

In Multiple trap cropping, it is recommended to grow several trap crops of different trap crop species to control various pests and also to control the target pests by combining plants whose growth stages increase attractiveness season-long. For example, Corn and Potato plants are combined and grown to control the wireworm population in the sweet potato fields. 

7. Push-Pull Trap Cropping:

                             

A combined system where a trap crop is grown around the perimeter of a crop to attract the target insect pest Act as a pull to the insects and a different plant is intercropped to repel or push the insect away from the cash crop. 

In Africa, A push-pull strategy uses sudangrass as a trap crop planted around the main crops and molasses grass grown within the field as a repellent Intercrop. 

8. Biological Control-Assisted Trap Cropping:

                             

In Biological control-assisted trap cropping, trap crops are cultivated in between and around the cash crop increasing the population of natural enemies that can help to control the number of pests naturally. For example, The Sorghum crop is used as a trap crop to manage the population of Cotton bollworms and also to increase rates of parasitism from various parasitic wasps.

9. Semiochemical-Assisted Trap Cropping:

                             

In this Semiochemical-Assisted trap cropping artificially hanging insect semiochemicals such as pheromone lures are used on a perimeter planting which attracts the smell of the opposite sex of insects. Genetically modified plants that emit semiochemical lures to attract the target pests are also used. For example, pheromone-baited flytraps hung on perimeter trees acting as trap crops have been highly suggested for fruit fly management in Papaya orchards.

Factors to consider when using trap crops:

 

1. The life stage of the insect you are targeting will be able to be controlled by the stage of the trap crop being grown.

2. Make sure you have enough trap crops and be sure that they're planted at the right location and the right time of year. So, they can correlate with your cash crop.

Limitations of Trap Cropping:

1. Trap crops usually target one or a specific pest.

2. Trap crops might end up costing more money than traditional pesticides, as they take up more land, water, and labor to use.