Agricultural Science

Agricultural pest, Crops attacked, their economic importance and control

Olawunmi Omosanya - Fri, 24th May, 2019 @ 11:43: AM

Pests in Agriculture:

In agriculture, any organism capable of causing damage to crop plant is termed a pest. To understand the differences between a crop and a plant, please read our article on plants versus crops here.

Basically, important pest of crop plants can be put into 6. These are:

  1. Insects
  2. Birds
  3. Monkeys
  4. Rodent
  5. Man
  6. Nematodes

Below is a table showing some insect pests, the crops they attack, the nature of damage / their economic importance and their preventive and control measures

Pests
Crops attacked
Damages caused/Economic importance
Prevention and control

Aphids

Soya-beans, Groundnuts, Cowpea and Legumes

i. Stunted growth in plants

ii. Galls, holes and spots on the plant's leave

i. Use of insecticides

ii. Uproot the infected plants

Army worm

Maize, barley and other cereals

i. Rate of photosynthesis is reduced

ii. The larva eats up the leave and stem

iii. Reduced plant growth and yield

i. Use of insecticides

ii. Hand picking

Bean Beetle

Bean seeds

i. They bore holes into bean seeds

ii. They reduce the quality of stored beans

iii. Reduce farmers income

i. Proper storage of beans

ii. Early harvesting

iii. Fumigating stores with lindane dust or phostoxin

Birds

Rice, Maize, Sorghum, Millet

i. They feed on grains in the field

ii. They reduce the quality of produce

iii. They reduce the farmer’s income

i. Early harvesting

ii. Use of scare crows

iii. Early harvesting

Cassava Mealy-bugs

Cassava and other tubers like yam

i. They twist the plant’s stem

ii. Reduced rate of  photosynthesis

iii. Reduced amount crop produce

i. Use of insecticides

ii. Use resistant varieties

iii. Early planting

Capsids / Cocoa mirids Cocoa

i. They transmit fungal diseases

ii. The inject toxic saliva into plants

iii. They cause staunted growth and reduce crop yield

i. Practice regular weeding

ii. Use of insecticides, e.g gammalin 20

Cotton Bollworm

Cotton

i. The larva feed on cotton seeds

ii. They destroy the cotton lint

iii. Premature fall of cotton boll

i. Burn all debris of the cotton plant after harvesting

ii. Use of insecticides

Cotton strainer

Cotton

i.. They pierce and suck plant sap

ii. They cause distortion in leaves

iii. They produce toxic saliva

iv. They can transmit disease

i. Use of insecticides

ii. Hand picking

Green Spidermite

Cassava, yam and cocoyam

i.. Reduce the rate of photosynthesis

ii. They feed on plant’s leaf

iii. They reduce crop produce

i. Use of insecticides

ii. Biological control

Leaf Beetle

Legumes; e.g Cowpea, soya-beans and Vegetables; e.g pepper and  okra

i.. They eat up plant’s leaf

ii. They reduce the yield of crop

iii. Reduced rate of photosynthesis

i. Plant seeds with resistant varieties

ii. Spray with insecticides

Leaf rollers

Vegetables; e.g Tomatoes, pepper, okra

i. Rolling and twisting of plant’s leaf

ii. Reduced rate of photosynthesis

iii. They reduced crop yield

Use of insecticides like vetox 85

Monkeys

Banana, cocoa, orange, mango

i. They eat up the fruits

ii. They reduce the quality of fruits

iii. The cause losses to the farmer

i. Shooting monkeys with guns

ii. Use of traps

Pod borer

Groundnut, cowpea and soya-beans

i. The larva make holes into pods

ii. They eat up plant’s seed

iii. They cause diseases to plants

iv. Reduced yield of crops

i. Practice crop rotation

ii. Practice early harvesting

iii. Spray with insecticides

stem borers

Cereals like rice, maize, corn and millet

i. Their larva bore holes into stems

ii. They eat up plant’s tissues

iii. Reduced plant growth

iv. Reduce crop produce

i. Use of insecticides like gammalin 20

ii. Practice early planting

iii. Practice crop rotation

Rodents; e.g rats, bush rabbit and squirrels

Fruits, cassava, rice, yam

i. They feed on crops

ii. They destroy the whole plant

iii. They increase the cost of production

iv. Reduced plant produce

i. Fencing farmland with wires and nets

ii. Use of traps

iii. Use poison baits

Thrips

Vegetables; e.g tomato, okra, onion

i. They cause browning of leaves

ii. They cause the wilting of plants

iii. They reduce crop yield

i. Use of insecticides

Variegated grasshopper

Tubers; e.g yam and cassava

i. The larva and adult eat up the leaves and stem of plants

ii. Reduced rate of photosynthesis

Reduced plant growth and crop yield

i. Spray with insecticides e.g Adrex 40

ii. Hand picking

Yam beetles

Yam

i. They bore holes into yam tubers

ii. Reduce the yield of yams

iii. They reduce the quality and market value of crop

i. Practice crop rotation

ii. Spray Adrin dust on yams before planting

 

Classification of insect pests

Our classification of insect pest will be based on their mode of feeding. These group of insect pest will include:

 

  • Biting and Chewing Insects

A major characteristic of the biting and chewing insect pest is the possession of mouth-parts which includes strong mandible and maxillae. Their mandibles and maxilla are used to bite and chew plant parts. Examples of biting and chewing insects include grasshoppers, termites, army worms, locust, beetles, leaf worms and so on.

 

  • Piercing and sucking insects

Piercing and sucking insects possess a strong mouth part called proboscis. The proboscis is a tiny and elongated mouth-part which enable some insects to pierce through plants so as to suck the liquid substances from their tissues. Examples of such insects include aphids, cotton strainers, mealy-bugs and white flies.

 

  • Boring insects

Boring insects will bore or make holes into crop plants. They end up destroying the tissues of plants, fruits and seeds through this mechanism. Examples of boring insects are stem borers, bean beetles and weevils.

Please read our article on pest of agricultural importance here

 

Effects / Economic importance of insect pest in crop production

  1. They cause reduction in the viability of stored produce.
  2. They destroy crop through their biting, chewing, boring, sucking and defoliation activities.
  3. While attempting to control them, the cost of production is increased.
  4. They render vegetables and fruits unattractive and unmarketable.
  5. Some are vectors of diseases. A vector is an organism that carry another disease causing organism.
  6. They generally reduce the yield of crops.
  7. They reduce the farmer’s profit.
  8. They may bring about the death of crop plants.

THANKS FOR READING - Please Help Share!



Amazing facts in Agricultural Science

A group of cows 🐄 🐄 🐄  is called a team, drove or herd.

People just prefer to call them herd


NOTABLE POINTS IN Agricultural Science

CONTRIBUTE TO THIS TOPIC | ASK A QUESTION