Aphids are very common sap-sucking insects that can cause a lack of plant vigor, distorted growth and often excrete a sticky substance (honeydew) on foliage which allows the growth of sooty moulds. Some aphids transmit plant viruses which can be a problem on strawberries, raspberries, tomatoes, cucumbers, dahlias, tulips, sweet peas and many other plants
Aphids range in size from 1 to 7mm (¼in or less) long. Some aphids are known as greenfly or blackfly, but there are species that are yellow, pink, white or mottled. Some species, like woolly beech aphid and woolly aphid on apple, cover themselves with a fluffy white waxy secretion and can be confused with some scale insects, mealy bug or whitefly. Most aphids feed on foliage, stems, and flowers but some suck sap from roots. There are more than 500 aphid species in Britain. Some species only attack one or two plant species, but others attack a wide range of plant hosts. Almost all plants can be affected, including ornamentals, vegetables, fruits, greenhouse plants, and houseplants.
The aphid is a key pest of sorghum and sugarcane in tropical and subtropical regions around the world, including Africa, Asia, Australia, and Central and South America. Although it was reported in Hawaii in 1896, it was first found in the continental United States on sugarcane in Florida in 1977. It was also observed on sugarcane in Louisiana in 1999. These infestations broke out in summer and declined by winter.
These aphid pests have infested grain sorghum in South and East Texas, southern Oklahoma, eastern Mississippi, northeastern Mexico, and central, northeast, and southwest Louisiana. In 2013, large populations of sugarcane aphids (Melanaphis sacchari) developed on sorghum plants. They produced large amounts of honeydew, which choked combines and caused lost grain in northeast Texas and Louisiana. Growers lost up to 50 percent of grain sorghum yield in infested fields during 2013. LSU Ag Center entomologist David Kerns said aphids have been a sugarcane pest in Louisiana since 1999, but in 2013 moved to grain sorghum for the first time. The 2013 infestation occurred late in the season and only caused harvest efficiency problems. The aphids produce sticky honeydew that can clog harvesters. According to Kerns, the pest arrived earlier and in higher numbers. “We’re seeing more acres affected. These aphids are being found throughout the whole state now.” He also stated that infestations, which began in the southern part of the state and moved north, can be fairly severe and cause yield loss.
The below article would further emphasize the damage caused by these pesky creatures.
Fighting back against an array of garden pests and diseases
By Kathryn McKenzie, Monterey Herald
There are few things more depressing than spending months nurturing a lovely rose, or delicious tomato, or beautiful plum tree, only to suddenly find it covered with weird spots and tiny insects.
The bad news is that these things can damage or even kill y
our precious plants. The good news is that there are some simple and sustainable solutions to get rid of the problem without using dangerous pesticides.
That’s the message at the twice-monthly pest and disease screening clinic held at McShane’s Nursery in Salinas.
On one recent Saturday, about a dozen people came to the free clinic with samples in hand, looking for answers to the pests that were plaguing their plants.
Aphids feast on a rose bush at a pest and fertilizer screening at McShane’s Nursery and Landscape Supply last week. (Vernon McKnight/Monterey Herald)
Nursery owner and general manager Steve McShane was there to console, diagnose and offer ideas for treating the various problems.
“When we’re talking, I tell them to go with what is least harmful to the environment,” said McShane.
Many homeowners have been coming in to find answers to aphid problems this year, he notes.
“This year has been worse because we’ve had a milder winter, and they’ve been able to overwinter successfully,” said McShane. “There’s been a lot of interest in aphid control.”
Aphids can attack many different kinds of plants, but are often most devastating for roses, sucking the life from new buds and leaves and causing them to wither.
However, it doesn’t take much to deter these soft-bodied bugs — even a well-directed spray of water will knock them off plants, McShane said, leaving them vulnerable to other insects and animals that eat them.
But if stronger measures are needed, he recommends horticultural oils such as neem oil, which has become part of the organic gardener’s arsenal in recent years. Derived from a plant native to Indian and Southeast Asia, neem oil is nontoxic to bees, birds and mammals but deadly for sucking insects. It’s also useful in controlling plant fungus.
Horticultural oils can help curb invasions of other sucking insects, like scale and mites, which weaken plants and are unsightly.
As for snails and slugs, McShane recommends the nontoxic snail bail Sluggo.
Another formulation, Sluggo Plus, can control other pests that chew on leaves, such as earwigs.
“Earwigs are silent but deadly,” said McShane, noting that many people don’t realize the damage these insects can do because they feed at night. Another chewing insect is the leaf miner, an agricultural pest that often shows up in yards adjacent to commercial produce fields.
Chewing insects can be controlled by application of spinosad, a newer pesticide that is considered to be nontoxic to most beneficial insects, animals, and humans.
Other garden scourges include fungal issues such as powdery mildew and rust, which often affect roses, but may also infest vegetables, fruits, and other plants. Another disease showing up on a plum tree branch that came into the pest screening clinic was shothole fungus, which McShane identified from its appearance.
“It looks like someone shot a shotgun at the leaves, with little black holes through them,” said McShane.
Other plant problems may result not from an insect pest or a fungal disease, but from a nutrition deficit. Another gardener brought in leaves that had yellowed, but the leaf vein remained green, a condition that McShane diagnosed as chlorosis.
McShane said the unusual appearance of the leaf is due to a lack of nutrients such as magnesium, and the answer is to use a fertilizer with micronutrients that replace what the plant is lacking.
Other problems that are specific to tomatoes are bacterial speck, which spreads rapidly and can wipe out a whole tomato crop. Speck is just what it sounds like: brown or black specks develop on tomatoes, and leaves can be affected as well.
McShane said careful watering can help prevent the spread of this bacteria, which lives in soil, and can spread to leaves when water splashes up from soil during watering. Copper fungicide sprays can also help control the problem.
Another tomato issue is blossom end rot, which causes tomato blossoms to fall before setting fruit, and can be caused by humidity and moisture. McShane recommends a spray that is specifically made to address this.
He notes that McShane’s pest and disease screenings have been quite popular this summer due to a renewed interest in gardening and the desire of local gardeners to keep their plants healthy despite the drought.
What’s even better, though, is the fact that it offers them a place to gather and share tips and advice.
“It’s a chance for gardeners to help one another,” said McShane.
Aphid infestations can destroy an entire plant, and if left untreated, they can spread to surrounding plants, as well. Taming an aphid outbreak can be difficult, but a treatment at an early stage can save the plant. If large numbers of aphids move into the establishing plants, insecticide dressings will not prevent damage, as each aphid must feed to get a dose of the insecticide, and in doing so contribute to the plant damage. Therefore we need a solution that helps protect our plants and trees from damage, while at the same time does not harm the environment in any way. So, how do we fight this pest?
At C Tech Corporation, we offer a safe and foolproof solution to deal with these tiny insects. Termirepel™ is a non-toxic, non-hazardous product that primarily repels insects from the application. It is a broad spectrum repellent which works against almost 500 species of pestering bugs thus efficaciously fending them away from the application. The best feature of this product is that it is environmentally safe and causes no harm to the insect as well as humans and the environment. It is available in masterbatch and lacquer form and as a liquid solution. To keep these insects at bay, this product can be coated in lacquer form or added in mulches or films. The repelling mechanism of the product would ward off the aphids and any other insect that could harm our plants.