Pollyphagous Pests– Agrictural field and plantation crops are attacked by several Insect-pests. Some are Pollyphagous in nature and some are mono and oligophagous. Feeding Patterns, Life Cycle and Systems of Major Polyphagous Insect-pests in the world are different from each other. The List of Major Pollyphagous Insect-pests:
- Locusts
- Grasshoppers.
- Hairy caterpillars.
- Cutworms.
- Termites.
Other Pests:
- Monkeys.
- Rodents.
The word polyphagus is made with use of two terms, ‘Poly’ + ‘Phagous’. The meaning of term ‘Poly’ is many, while the meaning of the term ‘Phagous’ is feeding on a food or simply an act of eating any food.
Polyphagous Insect-pests of Field and Plantation Crops
Helicoverpa Armigera 
Aphids on maize leaf
Polyphagous insect-pests are the most destructive group of insect and pests in agriculture. Economically, these pests are very important. Severe damage is done by pests to field and plantation crops. Their appearance and incidence is a major cause of heavy loss in crop yield. They can destroy all the vegetation of a certain area in a specific time of period when climatic conditions are favorable.
There are many polyphagous pests which attack on different field and plantation crops. Their periodicity is also different in different territories and countries in the world. But their nature and extent of damages remain same.
Nature of damage
- Damage is done in all parts of the plant.
- Young and developing plants are severely damaged.
Symptoms of damage
- Growth of plant become retarded.
- Less or no yield.
Area of Extent
- Cause famine.
- Large large area.
- Surrounding vegetation of other plant species.
Let’s start it……
Locusts
| S.No. | C.N. | S.N. | Distribution |
| 1. | Desert locust | Schistocera gregaria | All over the world |
| 2. | Bombay locust | Patanga succincata | Maharashtra and surrounding states |
| 3. | Migratory locust | Locusta migratoria | European and Asian Countries |
Desert locust is a universal importance pest. It is a serious pest of Asian and African countries. The incidence of bombay locust and migratory locust is less.
Occurrence: Rainy season, area of vegetation.
Nature of damage: Damage is done by both the nymph and the adult. Severe damage occurs during vegetation period when weather is suitable. They can cause famine.
Symptoms of damage and management: Plant becomes stunted, plant can become leafless less or no yield. Management is possible through biological, physical and chemical approaches. Chemically, Lindane is effective against locusts. Use 25-30 kg Lindane per ha.
Also Read: Pink stem borer in maize and its management.
Termites
Termites are social pest. Their family members include, king, queen, workers and soldiers.
Common Name: Termite, white ants.
Scientific Name: Various, Odontotermes app.
Order: Isoptera
| S.No. | Family | Remarks |
| 1. | Kalotermitidae | Feeds on dead substance, targeted plant-crops are- tea, coffee, rubber, cacoa teak etc. |
| 2. | Hodotermitidae | Mainly Asian countries, targeted plant-crops are- eucalyptus, grass. |
| 3. | Rhinotermitidae | They are subterranean habit’s. They target furniture, doors, chairs etc. in a house. |
| 4. | Termitidae | Very large family, they cover more than 50%, economically important family. Serious pest of field crops. |
Damage caused by rhinotermitidae
Occurrence: All seasons.
Nature of damage: Crop is attacked by the workers. Fresh parts of plant-crops are devoured by the insect. They can eat whole parts of a plant. Small plant becomes dried instantly. Termites attack plant for their moisture. Attacks are severe during dry season.
Symptoms of damage and management: Plants become dried, sudden death in field crops, reduced yield. Heavy irrigation and application of chlorpyriphos (0.5 g active ingredient) is required. Lindane can also be applied.
Hairy Caterpillars
| S.No. | C.N. | S.N. | Order | Family | Distribution |
| 1. | Red hairy caterpillar | Amsacta moori | Lepidoptera | Arctiidae | Asian countries |
| 2. | Bihar hairy caterpillar | Spilosoma obliqua | Lepidoptera | Arctiidae | Bihar and its surrounding states, and Rest of India |
Hairy caterpillars are one of the most destructive insects of the field crops. There range of host plants are very large from field crops to horticultural plant-crops.
Occurrence: Vegetation period.
Nature of damage: Damage is done by the full grown and young caterpillars. They eat growing parts of plant e.g., new leaves.
Symptoms of damage and management: Denuded leaves. Use systemic insecticides. Large quantity of insecticide is required while controlling adults. So try biological, cultural and physical methods.
Cutworms
| S.No. | C.N. | S.N. | Order | Family | Distribution |
| 1. | Gram cutworm | Ochropleura flammatra | Lepidoptera | Noctuidae | Asian and European countries |
| 2. | Greasy cutworm | Actitud ipsilon | Lepidoptera | Noctiudae | European, African, Asian countries and Oceania. |
Occurrence: Vegetation period. Sporadic in nature.
Nature of damage: The larvae are surface graders and cut the crop from the ground level. They cut more plants but eat less.
Symptoms of damage and management: Plants are cut down by the insects. Establishment of bird perches in gram will help in controlling the insect. Chemically chlorpyriphos can be used.
Other insects: Helicoverpa armigera.
Other Pollyphagous Pests of Field and Plantation Crops
Monkeys
There are different species of monkeys. They attack on all types important crops from kitchen garden to commercial agri-plots.
Rodents
Rodents include rat, rabbit etc. Both rodent and monkey are major pest of plantation crop like coconut and guava.
Management: Use indigenous technology against monkeys. Poison baits are very effective against rodents.
Reference:
- Sidar, Yogesh (2014). Seasonal incidence of pink stem borer in maize. M. Sc., ag. Thesis. IGKV, Raipur, 2014.
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