Potato Pests

Potato Pests

Two Spotted Spider Mites
Spider mites are tiny, spider-like insects that produce webs and are generally found on the undersides of leaves. Mite damage in potatoes is a minute stippling of the leaves and sometimes a bronzing. Mites reproduce rapidly and can build up to unmanageable populations in just a few days under the right conditions.
In most cases, mite outbreaks in potatoes are an induced problem, brought on by management practices aimed at other pests. Application of nonselective pesticides, such as pyrethroids, certain carbamates and organophosphates, negatively impact mite predators and allow spider mites to increase. Also, the proximity to certain crops such as corn, alfalfa, and mint, proximity to dusty roads hot, and dry weather tend to harbor mites.
Spider mites overwinter in leaf litter and other debris on the soil surface. The two-spotted spider mite has a very wide host range and in spring colonize with in many weeds, crops, and native plants. They thrive in hot weather and can build up large populations rapidly during summer.
Mites reproduce better on stressed plants so check areas of fields that tend to be stressed for some reason (e.g., dry spots, low spots, and edges). It is also smart to check the edges of fields nearest to crops likely to harbor mites. Try to recognize mite populations before significant damage is noted and certainly before webbing is noticeable.
Remedies
PureAg Dream Neem contains Azadirachtin to confuse the eating and reproduction cycles.
PureAg Pest Control contains horticultural oil, insecticidal soap, plant essential oils (e.g.,Thyme Oil, Garlic Oil, Corn Oil,
Clove Oil, Citric Acid, Peppermint Oil, Rosemary Oil, Geraniol ). This is a knock down product that will kill pupa, larva, and adults.
Psyllids
Although all psyllid species are different, they basically go through a similar process in their lifecycle. Within days of emerging, they mate and lay up to 500 eggs over 21 to 40 days. In some areas, they will lay up to 800. The eggs are tiny, but you usually can see them with the naked eye. They range in color shades from yellow to white or clear. They are connected to the plant by tiny threads. The eggs can be laid in clusters anywhere on the plant, but often are on the edges of leaves where they are easily seen.
Adults are brown or green or a mixture of both, and have white or yellow markings. Winged adults look similar to a small cicada or a large aphid. Nymphs look a little like scale. Most varieties will have up to five generations over the season, if not more. At average temperatures of 65F, the lifespan of a psyllid is about 35 days. During that time, they devour the sap in your plants.
Psyllids want that sweet, sticky sap running through stalks, leaves, and offshoots. They access it by inserting a stylet into a soft part of the plant and then suck out the sap. The problem becomes worse as the infestation reaches large numbers. Part of the eating cycle is excretion. Psyllids excrete honeydew, which is attractive to ants and wasps because of the sweetness.
Some species also excrete a waxy substance called pellets, strands, or lerps. These are honeydew droplets that have crystalized.
If you suddenly notice wilting, but can’t see any cause, check carefully for psyllids and their eggs. They’ll jump and scatter when you come near. Sticky plants that look dirty are usually covered in honeydew. This is excreted by psyllids (as well as aphids) and causes sooty mold.
The plant foliage turns yellow or mottled and new shoots are yellow. Plants that are subject to an infestation often lose their energy to grow and produce.
There are many ways to control psyllids, but keep them out by being proactive. Psyllids overwinter in weeds, so make sure you clear these away from plants, especially trees.
Remedies
PureAg Dream Neem applications make the sap unpalatable to psyllids and any other sap-sucking or leaf-munching pests. Use it regularly.
PureAg Pest Control is a good option when you notice the presence of psyllids and want a knock-down effect.
Colorado Potato Beetle
Bacillus Thuringiensis has selective and effective control of the Colorado potato beetle. The larvicidal activity of the bacterium is due to the parasporal crystal that is produced by the bacterium at the time of sporulation. Protein toxins must be ingested in order to be active. After being eaten, the crystal is solubilized. The portion of the toxin molecule, binds to specific sites on the membrane of the midgut cells and disrupts osmotic balance. The cells swell and ultimately rupture allowing gut contents to enter the body cavity. The insects die shortly afterward.
A number of factors influence the larvicidal activity of Bt (Bacillus Thuringiensis), such as the age of targeted larvae, temperature, spray rate and coverage of the plants, timing, number of applications and inactivation by sunlight. Younger larvae are the most susceptible. Although adults are not susceptible, they may be repelled by Bt-treated plants.
Distinct advantages of Bt formulations over that of conventional chemical pesticides are safety for applicators and lack of activity on nontarget organisms, including natural enemies. In the irrigated desert the insect biodiversity in Bt treated plots is unaffected.
Fungal pathogens are important natural enemies of a wide variety of insect and mite pests in virtually every agro-ecosystem.
Beauveria Bassiana and Metarhizium Anisopliae have shown to be the most effective in controlling the beetle. The fungus can be stored for fairly long periods especially when it’s kept cool. Formulation of spores also enables application of the fungus using conventional spray equipment.
Factors that effect its larvicidal activity include: temperature, humidity, age and stage of the insects, timing and number of applications, dosage, agricultural practices, and deactivation by sunlight. The fungus invades the insect's body, usually through the cuticle. After invading the host, the fungus grows throughout the body and under proper conditions, will sporulate on the surface of the host cadaver. This may take place on the host plant or in the soil prior to or during the pupation stage. Another benefit of using fungi is overwintering adults may also become infected in the soil. The production of secondary inoculum on the host insect may contribute to increased mortality both on the host plant and in the soil. In addition to killing larvae, the fungus has been reported to slow the feeding rate of beetles that have received a sublethal infection.
Remedies
PureAg Biologic Army has three strains of Bacillus Thuringiensis, the fungi isolates Metarhizium Anisopliae and Beauveria Bassiana, that are known to infect over 200 insect pest species, and are generally considered safe as an insecticide.
Aphids
Fungi are the only insect pathogens currently used for control of aphids. Because aphids obtain their food with piercing and sucking mouthparts, pathogens that must be ingested, such as bacteria and virus, are not effective. These fungi have more complex life cycles and, under conditions of high humidity, are often responsible for crashes in aphid populations. Very low densities of the green peach aphid may be detrimental to potatoes due to the transmission of leaf roll virus and other plant pathogens. It is important to note that some agricultural practices may interfere with fungi and other natural enemies of potato pests insects. Certain fungicides used to control plant disease in potatoes could interfere with infection of the aphid.
Remedies
PureAg Biologic Army has three strains of Bacillus Thuringiensis, the fungi isolates Metarhizium Anisopliae and Beauveria Bassiana that are known to infect over 200 insect pest species and are generally considered safe as an insecticide.
PureAg Dream Neem and PureAg Pest Control follow up applications will provide the knock down power for the adults and interfere with the eating and reproduction cycle of these aphids.
Give us a call, we're here to help.