A few months ago, our neighbor became the proud grower of a tomato seedling.
The potted plant was growing well on her balcony, and she was elated when a few weeks later, a couple of small green fruits started to emerge.
While the excitement of growing tomatoes was still fresh, my neighbor noticed that her plant’s leaves were slowly turning pale. Within days, the leaves turned yellow, and the fruits stopped growing. Finally, her little tomato seedling completely dried up and died.
Growing a food crop in your home garden is a joy. But nothing prepares you for the disappointment that the death of a garden plant causes. Our neighbor was dismayed by the sudden death of her beloved tomato plant as she didn’t know what had caused it. She turned to us for help and turning plant detectives, and we uncovered evidence to establish the specific cause for the plant’s demise
The evidence: white cottony growth and white dust specks on the dead tomato plant
Our examination of the photos of the dead tomato’s branches showed us a white cottony growth on the tiny branches. We thus had the first clue that the dead plant had a mealy bug infestation as it had a white cottony growth.
Further examination of the dead tomato’s pictures showed that it also had white dust-like specks on the underside of its leaves. We identified such dust as the presence of a white-fly infestation.
Our verdict: We thus established that after an initial infestation by two plant-sap-sucking pests, the mealy bug, and the white fly, our neighbor’s tomato plant had become weak and eventually died.
How we solved the mystery leading to the death of our neighbor’s tomato plant?
Plant-sap-sucking pests are a group of insects that cause a plant to become vulnerable by sucking into the plant’s sap. Some sucking pests also carry plant pathogenic microorganisms in their saliva, which they introduce into the plant when the insect feeds on plant sap.
Whiteflies, mealybugs, aphids, thrips, and leafhoppers are common plant-sap-sucking pests that gardeners may not notice until the infestation is severe or their infested plant has died.
What do plant-sap-sucking pests do?
Plant-sap-sucking insects pierce the plant with their sharp mouthparts and feed on its nutrients by sucking out its sap.
These tiny insects often hide on the underside of leaves, making it difficult for gardeners to spot them.
In our investigation into the mysterious death of our neighbor’s tomato seedling, we wondered if a plant-sap-sucking pest infestation had caused its demise.
What are Mealybugs?
They are a type of scale insect which you can find in moist and warm plant spots where they feed on the sap and transmit plant diseases.
Mealy bug infestation can lead to an ant infestation as both insects live symbiotically, with the mealy bug feeding the ants with a honeydew they excrete. In return, the ants protect the mealybugs from predators.
Mealybugs occur on most plant parts, including roots, shoots, and fruits, where they favor crevices. As they attach themselves to a plant and cover themselves with a white waxy powder, they get their name, mealy bugs.
What are whiteflies?
Whiteflies are a type of plant bug which feeds on the undersides of plant leaves. One sign of whiteflies is the circular pattern in which they lay eggs below leaves.
Whiteflies are masters at masking their presence on plants, and they multiply quickly, with most gardeners unlikely to notice the pest’s rapid population rise on a plant or garden.
Whiteflies congregating in the undersides of leaves can destroy the plant they infest as they tap into its phloem tissue, reducing its turgidity. As a result, most white-fly-affected plants wilt fast and die.
Like mealybugs, whiteflies also secrete honeydew which leads to the formation of fungal growth.
Knowing what pest you are against in your garden goes a long way in managing them.
Gumtree Sticky Traps can help home gardeners identify a problem when they catch flying plant-sap-sucking pests.
How can you monitor mealybugs and whiteflies?
Mealybugs are immobile, and they occur mostly in plant crevices. However, they do occur in soil on roots and fruits. They appear like a white cottony growth and may be present on the underside of leaves.
Adult whiteflies are flying insects and may appear like specks of white dust flying around a plant. Gently shaking a plant may lead to a mass of them flying, indicating their presence.
Gumtree Yellow Sticky Trap can help detect whiteflies’ presence as some get caught on such a trap hung on a plant.
Mealy bug and white fly control measures:
Sucking pests are not simple or easy to control.
Gardeners must ensure that they don’t over-fertilize their plants. Lush foliage growth from high nitrogenous fertilizer application attracts plant-sap-sucking pests like mealy bugs and whiteflies.
To avoid rapid foliar growth, gardeners must limit the quantity of nitrogenous fertilizer they apply. Using organic nitrogen sources limits rapid plant foliar growth as such products have low nitrogen levels.
If the number of mealy bugs is few, you can prick them with a sharp pointed object like a toothpick, pry them off the plant, and discard them in the bathroom drain.
Sometimes, if mealy bugs infect only one or two leaves, you can remove them and save the rest of the plant.
Regularly spraying a neem emulsion (an emulsion is a solution you make from the neem concentrate you purchase from a manufacturer) early in the morning or after the evening helps to control mealy bugs.
Direct the neem spray toward the entire plant, including roots, flowers, fruits, shoots, and leaves, as mealy bugs occur everywhere on a plant.
If any individuals escape the neem spray, they could create a fresh population and continue pest damage to the plant.
Due to their flying nature, whiteflies are more difficult to control than mealy bugs. Gumtree’s Yellow Sticky Trap traps white flies and prevents their further multiplication.
First, however, gardeners must deal with the numerous whiteflies on the undersides of leaves. A thorough spray of neem emulsion regularly over several days helps to control white flies.
In the case of both mealy bugs and white flies, it may help to discard a plant heavily infested by them as they may pose a danger to other unaffected plants. Isolating a plant away from others in the garden also helps to limit plant-sap-sucking-pest exposure of unaffected plants.
We hope you found our detailed description of mealy bug and whitefly control useful for gardening.
Solving the mystery...
Just like mosquitoes cause diseases that weaken the immune system in humans, sap-feeding pests cause the plant to become vulnerable to fungal infections and viruses. Whiteflies, aphids, thrips and leafhoppers are sap-feeders that often go unnoticed.
They pierce the plant and feed on the nutrients by sucking out the sap. These tiny creatures often hide on the underside of leaves which makes them difficult to spot. Could it be possible that a sap-feeding pest infestation caused the demise of the tomato sapling?
The answer lies in the analysis of dead sapling. Photos of dead branches show growth of a fungal moss on the tiny branches. This indicates that the plant may have succumbed to a fungal infection caused by a well hidden sap-feeding pest infestation.
Whiteflies are masters at masking their presence on plants. They multiply quickly and are hardly ever noticed. They colonies the underside of leaves and can completely destroy a young sapling within a week or sometimes less.
Why whiteflies are a problem...
They infest vegetable and ornamental plants
Their feeding causes yellowing of leaves
Heavy infestation causes leaves to fall off
Their sugary secretions cause black sooty mold growth on plants
Certain species transmit viruses in vegetable crops
Keeping whiteflies under control...
Knowing what pest you are up against goes a long way in managing them. Using Gumtree Sticky Traps can help home gardeners identify a problem when they catch one. Not only are Gumtree Sticky Traps far superior to anything else in the market, they are also made without the use of toxic materials.