Combating Rose Aphids: A Guide To Identify, Understand And Manage This Common Rose Pest

Aphids are tiny, soft-bodied insects that feed on the sap of plants. They are small, oval-shaped insects that range in colour from green, yellow and black. They have long, slender antennae and two tubes (known as cornicles) that extend from the posterior end of the body. At different growth stages, the appearance of aphids can vary, with nymphs being smaller and lighter in color than adult aphids. 

Aphids are one of the most common pest of roses which can cause significant damage to the plants. Aphids are often referred to as “plant lice” because of their feeding habits, which can cause stunted growth, distorted leaves and flowers and even death of the affected plants. Roses are especially susceptible to damage from aphids, as the insects feed on the young, tender growth of the plants. Currently, there is a growing concern among rose growers in India about the increasing prevalence of aphids, and many are looking for effective ways to control these pests.  

Type of Infestation

Aphids are a type of sap feeder, as they feed on the sap of the rose plant’s stems, leaves, and buds. 

Scientific Name: Macrosiphum rosae 

Most Affected States

Aphids are a common pest of roses in many regions of India, with the highest levels of infestation typically occurring in areas with warm, humid climates. Some of the major affected states in India include West Bengal, Uttar Pradesh, Maharashtra and Karnataka.  

Symptoms of Rose Aphids

• The presence of aphids on rose plants can be easily detected by the presence of distorted leaves, yellowing of the foliage and a sticky residue known as honeydew on the leaves and stems.
• Premature falling of buds and fading of flowers.
• In heavy infestations, the plants may become stunted and may even die.

Control Measures

A combination of different control measures is often required to effectively manage aphid infestations in rose crops. The following are some common IPM practices used to control aphids. 

Cultural Measures

• Sowing time: Planting roses during the proper season can help to manage aphid populations. In many regions, planting roses in the September or October month can help to reduce the amount of overwintering aphid eggs and prevent infestations early in the growing season
• Intercropping: Intercropping roses with companion plants, such as marigold can also help to manage aphid populations. These companion plants can act as a trap crop by attracting aphids away from the roses, and they can also release natural insecticides that help to control aphids.
• Trap crops: In some cases, planting a trap crop can be an effective way to manage aphids. For example, planting nasturtiums near roses can attract aphids away from the roses, reducing their population and minimizing damage to the roses.

Physical Measures

• Light traps can be used to trap and kill adult aphids. For a hectare 4 light traps can be installed for effective trapping.
• Barriers such as row covers can be used to physically exclude aphids from the rose crops. This can be especially effective when the roses are in their early stages of growth.

Mechanical Measures

• Collection and destruction of heavily infested plant parts is an effective way to reduce the aphid population. This should be done before the pests have a chance to lay their eggs.

• Sticky traps can be used to monitor aphid populations and to help reduce their numbers. Yellow sticky traps are particularly effective in attracting aphids.
• Tapas Yellow Sticky Traps @ 6-8 traps per acre can be used for the effective control of aphids in rose plants.

Biological Measures

• Predators – Ladybugs and lacewings can be released to control aphid populations. These predators feed on aphids and can help to keep their numbers in check.
• Parasitoids – Wasps help to control aphid populations. The wasps lay their eggs inside the aphids, killing them in the process.
• Katyayani Activated Neem Oil Biopesticide contains activated azadirachtin which when used at the rate of 5 ml per liter water with a 12 days interval between each spray can effectively control aphids in rose crop.
• Amruth Alestra Liquid (Bio Insecticide) contains strains of naturally occurring entomopathogenic fungus Verticillium lecanii which comes in contact with the cuticle of the aphids and colonizes them. The recommended dosage is 2ml per liter of water.

Chemical Measures

Chemical control is often necessary when other control measures are not effective. The following are some commercial chemicals that are commonly used to control aphids in rose crops:  

Product Name	Technical Content	Dosage
Confidor Insecticide	Imidacloprid 17.8% SL	0.75 – 1ml/lit water
Actara Insecticide	Thiamethoxam 25 % WG	0.5gm/lit water
Anshul Ikon Insecticide	Acetamiprid 20% S.P.	0.5gm/lit water
Tafgor Insecticide	Dimethoate 30% EC	1.5 – 2.5ml/lit water
Asataf Insecticide	Acephate 75% SP	1 – 1.5gm/lit water