Major pests of Chrysanthemum are:-
1.Chrysanthemum aphid: Macrosiphoniella sanborni, Myzus persicae
Symptoms of damage:
- Nymphs and adults suck the sap from under the surface of leaves and terminal shoots.
- Stunted growth of the plant
- Curling of leaf
- Withering of flowers.
Identification of the pest:
- Aphids are black (or) chocolate brown in colour
Management:
- Aqueous spray application of Vercillium lecanii (Vertilec) @ 15 g/lit (108 CFU/g)
- Application (ultra low volume) of the entomogenous fungus V.lecanii
- Neem formulations can be used in rotation with regular insecticides
- Spray any following insecticides malathion 50 EC @ 1 ml/l of water,
2.Chrysanthemum Thrips: Microcephalothrips abdominalis
Symptoms of damage:
- Infest the flower heads.
- Lacerating the sepals and petals causing abrasions
- Heavy infestation – damage to corolla, stamens leading to premature flower drop.
- It transmits the tomato spotted wilt virus, necrotic spot virus to many floricultural crops.
Identification of the pest:
- Adult – slender, white to black in colour
Management:
- Grow resistant varieties like
- Chandrika, Bangalore Local Yellow Double, M-7, Pankaj and Yellow Star.
- Field sanitation.
- Remove weeds that harbour virus from inside and outside the greenhouse.
- Yellow or blue sticky traps can be used for mass trapping of thrips.
- Blue traps – more effective for mass trapping than yellow traps.
- The release of nymphs and adults of predatory minute pirate bug, Orius insidiosus.
- Spray dimethoate 30 EC @ 1 ml/litre or fenitrothion 50 EC @ 1.0 ml/litre malathion 50 EC @ 2 ml/litre
- Application of spinosad very effective against thrips.
3.Chrysanthemum Flower feeder: Helicoverpa armigera
Symptoms of damage:
- Caterpillars feed on buds and flowers.
Identification of the pest:
- Young caterpillar – yellowish white and gradually green in colour
- Adult – medium sized, light brown and V-shaped speck on the forewings
- Male – forewings are green in colour
- Female – forewings are brown in colour
Management:
- Field sanitation
- Collect and destroy damaged buds and flowers
- Set up pheromone traps with Helilure at 15/ha
- Spray nuclear polyhedrosis virus (Ha NPV) at 500 LE or 1.5*1012 POBs/ha
- Encourage the activity of parasitoids campoletis and chelonus
- Spray carbaryl 50 WP 2g/lit.
Source-
- TamilNadu Agritech Portal
