An aphid infestation is nothing to joke around; it can destroy a garden very quickly. If you want to understand how aphids attack your plants, it is important to know the answer to: what do aphids eat?
If you take care of plants in your daily lives, you do not need any introduction to an aphid infestation.
Aphids often feed on soft plants that they can easily puncture and consume the plant sap, the main source of nutrition for them.
To deal with aphids, you need to know how these insects do their damage, what their food chain looks like, and how their life cycle works. In this blog, we will introduce all these things!
What Plants Do Aphids Eat?
Apart from 1-2% of the aphid species, most choose only one host plant to eat, and they are loyal to that plant. Due to this reason, they are called monophagous pests.
Some common plants that aphids can infest are crops like corn and cabbage. Melons, underground vegetables, and ornamental plants are also good targets for aphids.
About 1-2% of species of aphids, such as the green peach aphids, can derive nutrition from multiple types of plants.
In most cases, aphids become natural enemies of plants with soft stems from where they can extract the sap. This includes flowering plants, fruit trees, and vines.
Aphids may attack different plant areas, like stems, leaves, and roots. Root aphids live in the soil around the plant instead of living on the plant itself.
How Do Aphids Eat?
Aphids find host plants using their sense of smell and touch, using their antennas. Once they have found a good target, they inject saliva into the stems, leaves, or roots to make it easy to feed.
The insects use needle-like mouthparts known as stylets into the softer parts of the plant to extract sap from the host plants.
First, they attack the xylem of the plant and then the phloem tissue, where they find the sap.
What Nutrients Do Aphids Get From Plant Sap?
Plant sap is one of the main food sources for aphids. Plant sap is a rich source of sugar, nitrogen, and other nutrients.
Aphids are mostly interested in the nitrogen available in the plant sap. The sap also contains water.
The sugar is something that comes along with it, and they just carry it around in the form of honeydew and excrete it out later on.
Most aphid populations are found on plants that are known to have a high content of nitrogen. They are also likely to look out for plants that have a high moisture content.
How Some Bacteria Help Aphids Process The Sap
Plant sap gives aphids nitrogen, sugar, and moisture. But one thing that is not directly available in sap is amino acids.
Aphids have a symbiotic relationship with a bacteria called Buchnera Aphidicola that helps them break down plant sap into multiple amino acids inside the insects’ bodies.
Aphids don’t just feed on plant sap – they end up inadvertently weakening the plant they feed on.
Extracting the sap makes the plant susceptible to disease. It can also cause deformities in new growth.
Moreover, the sticky honeydew they secrete can create mold and attract other insects to the infected plant.
How Ants and Aphids Benefit Each Other
This heading might seem out of place in an article about what aphids eat. But hold on, we assure you, this is relevant!
Ants “milk” aphids for the honeydew that they carry around. Ants behave as bottom feeders to aphids, using them as a secondary source of nutrition.
Interestingly, even though ants are predators of most other bugs, they don’t attack aphids as long as they are extracting honeydew.
In fact, ants become protectors of these little creatures, herding them and keeping them safe from other predators. In this way, the two have a symbiotic relationship with each other.
How Aphids Harm Plants in Many Ways
Aphid infestations are terrible for plants. It is not just that they take out the plant sap – they cause a lot of damage in many ways.
They are one of the worst pest infestations that can occur to your plants, and knowing what they do can help you prepare for an attack.
We have already talked about plant sap as one of the main diets of aphids. But what does this mean for your plant?
Reduction in Nutrients
Plant sap consists of sugar and additional nutrients required for a plant’s growth. When aphids take away these nutrients, you will notice your plant turning from green to yellow and then brown, showing signs of nutrient deficiency. The plant loses its nutrients and can ultimately die an early death.
Transmission of Disease
Aphids carry plant viruses. When an aphid pierces into a plant to extract nutrients, it can transmit viruses that affect the plant’s health.
If the aphids start multiplying, the aphid eggs also become carriers of the same disease, affecting more plants. The infected plants are more likely to die from the virus than from the aphid infestation.
Toxic Saliva
Just like an insect’s sting is harmful to a human being, an aphid’s sting leaves the plant vulnerable.
Some aphid species have toxins in their saliva, and when they pierce a plant, the toxin gets transmitted. The main sign of toxic saliva from aphids is the yellowing of leaves in a plant.
Development of Sooty Mold
Patches of sooty mold around leaves and stems are another marker of aphid infestation. The mold forms because of the honeydew that these bugs secrete all over the plant.
As unpleasant as it is to look at, this mold is a fungus that can be a health hazard for crops. Moreover, it attracts other pests to the crop.
Frequently Asked Questions
Should I kill aphids?
Yes, if you find aphids infesting your plants, it is best to get rid of them quickly. These pests can reproduce at lightning speed and in no time destroy the whole garden.
Spraying your garden with insecticidal soap, releasing beneficial insects such as lacewings and beetles, and regular pruning of infested leaves are the best ways of taking care of aphids.
What do aphids turn into?
Aphids are adult pests; they are not larvae. Most species of aphids overwinter. Female aphids leave their eggs on the leaves of their host plants.
When their eggs hatch, they are called nymphs. The nymphs do not have a pupal stage and directly grow into adult aphids.
Aphids shed their exoskeletons four or five times, like most other insects (called molting).
Do banana peels keep aphids away?
Yes, banana peels are a good pest repellent that can work on aphids as well. You can cut up banana peels and bury them about two inches deep in the soil of plants that are prone to infestations. Most aphids will redirect themselves to the peel, which will protect your plants.
Can aphids bite you?
No, aphids are not capable of biting humans. They have sharp mouthpieces which they use on plants, but those cannot cause any harm to animals or humans.
Few species, like the pea aphid and gall-forming aphids, can bite humans and cause minor skin problems.
Final Words
Aphids are not like other common garden insects that you can leave alone. You must control these pests at the first sign to avoid as much damage as possible.
The best idea to tackle aphids is to spray soapy water using a spray bottle on the plants or else release aphid predators like ladybugs, lady beetles, parasitic wasps and green lacewings in your garden. Thank you for reading!
5 Comments. Leave new
These are podocarpus aphids, Neophyllaphis podocarpi Takahashi. Podocarpus is a commonly used plant is warmer regions.
Thanks Buglady. We will find some links to add to the posting.
My plant has what looks like boxelder bugs on it. this is really confusing me.
What is this bug sucking up the yellow powder inside Calla lily flower?
Today, in early Oct., we found several colonies of this yellow aphid, (Oleander Aphid), on our milkweed plants. This is the first time I’ve ever seen them in our area. We’re in the Halifax area in Nova Scotia, Canada.