Potato moth (Phthorimaea operculella Zell) is a dangerous quarantine pest that can cause significant damage to nightshade crops such as potatoes, eggplant, tomatoes, tobacco, pepper. The territories where the mole has settled are huge. Today it lives in more than 70 countries of the world. And here in the Kuban it was first noticed quite a long time ago - 1981. What is the danger of potato moth to us gardeners? That can destroy all the potato stocks in the cellar. Now, let's talk about what a potato moth is, measures to combat it.
Potato Moth - stages of development and lifestyle
The countries of Central and South America are the birthplace of potato moth. How she looks like? This is a very small, inconspicuous, nondescript butterfly. The wingspan is a little more than a centimeter - only 12-16 mm. The front wings are gray in color, they have large dots, stripes, and the rear ones are monophonic with uneven terry edges.
Moth for the entire period of its existence passes through several stages of development - a butterfly, an egg, a larva, a pupa.
The whole development cycle takes 22-30 days in the summer, and in winter the same process takes much longer - 2-4 months.
On potato bushes, moths are hard to spot. This is not a Colorado potato beetle, which at different stages of development can be easily seen at any time of the day. An active moth becomes early in the morning, before sunrise, or late in the evening, after sunset.
But during the day walk along the edge of the potato field, disturb the bushes. If the site is infected, then you will see how butterflies, very similar to the usual clothes moth, fly above the plantings and, flying 2-3 m, sit on leaves, stems, ground, merge with the background, immediately become invisible because of its small size.
The life of the pest in the butterfly stage is approximately 3 weeks. During this time, she manages to lay 50–200 eggs on the leaves below, on the stems, potato tubers, and fruits of other nightshade plants.
In 5-15 days, the larva of a moth - a caterpillar ripens in an egg. This is the most dangerous stage of pest development from the point of view of gardeners, since it is the caterpillars that do the most damage to potatoes, tomatoes, eggplants, and other vegetables, damaging tubers, fruits, stems, leaves.
The larva (caterpillar) usually has a yellow-pink or slightly greenish color, the body length is from 1 to 1.3 cm. The life span of the caterpillar is 10–48 days, during which time it sheds four times.
In the pupal stage, it passes on plants or soil, crevices of walls or floors, if it enters a vault or cellar.
In winter, a caterpillar or pupa is carried out in soil close to the surface or under abandoned plant debris. And in spring, gray butterflies fly out of overwintered pupae.
Potato moths of any stage of development can be found in the garden all season, from early spring to late autumn. And after laying, for example, infected tubers for storage under favorable conditions, the development of the pest also continues in the winter.
Moth caterpillars are particularly survivable. Potato tubers freeze, become unfit for food when the temperature drops to -1ºС, but the pest will survive in such conditions.
The best conditions for the moth will be a temperature of + 22–26 ° C with an air humidity of not more than 80%. If the air warms above + 36 ° C or cools below -4 ° C, then the insect will die, and it does not matter at what stage of its development it will be.
Fighting moths on potatoes in the garden
So how do you determine if a moth has settled in our garden? Only after a thorough inspection of plants. The first thing that catches your eye is the presence of excrement on the stem, leaves, and fruits.
Caterpillars penetrate inside tomatoes, eggplant, pepper through the stem or from the opposite end of the fruit, where the flower was. And in the potato tubers - through the eyes, the place of attachment of the stolon or minor damage, cracks.
In vegetables, potato tubers, there can be up to 6 larvae simultaneously. But even one is enough to spoil the whole fruit.
Potato growers suffer large losses from moths. For this reason, it is important to prevent the pest from entering the tubers by conducting regular preventive measures.
- First, potatoes must either be planted deeper than usual, or spud more often and higher. The height of the soil layer above the tubers should be at least 15 cm. It is noted that most often the pest is introduced into tubers located close to the surface of the earth.
- Secondly, potatoes should be removed until the tops have dried. 1-2 weeks before harvesting, the green mass is mowed, immediately immediately removed from the field so that the tracks do not invade.
- Thirdly, if you notice traces of the pest in your field, then try to immediately treat the entire plot using chemical preparations. From the moth use the same means as from the Colorado potato beetle - for example, fastak, decis. Only 20 days after processing the tubers can be eaten.
- Fourth, the dug up tubers should be removed from the field as soon as possible, since just a couple of hours is enough for the butterflies to lay eggs and spoil the crop.
The fight against potato moths, of course, will add trouble to gardeners. But your efforts will not be wasted - you save the harvest.
How to deal with potato moth in the cellar
Before you put the crop in storage, if you notice the presence of a pest in your area, you need to process the tubers. How to process potatoes from moths? There are various ready-made preparations, as well as those that are easy to prepare by yourself, combining several ingredients.
The moth remedy is a mixture of two biological preparations: lepidocide and planris. The first drug is just needed to deal with this pest, and the second - to prevent fungal diseases.
The solution is prepared quite simply. The amount of ready-made solution depends on the size of your crop.
In 100 l of water you need to add 2 l of lepidocide + 0.5 l of planris. Potatoes for 5-10 minutes are lowered into the mixture immediately (it is not recommended to store it). Then the tubers are dried.
After such processing, the crop can be safely stored. For food, it will be suitable after 2-3 days. By the way, such biological treatment will be an excellent prevention before planting potatoes.
There is another option for processing potatoes, where a mole appeared - a 1% solution of bacterial preparations (lepidocide, dendrobacillin or bitoxibacillin). About 150 liters of such a solution will be needed for 150 liters of water. The treatment is the same: tubers need to be lowered into the mixture for 15–20 minutes.
Biological preparations have a short shelf life of 1-2 years.
To withstand the entire crop in bio-solution is a laborious operation. Rather, it will be on the shoulder to those who grow potatoes in small volumes for themselves. Therefore, it is advisable to pay more attention to preventive measures.
In addition, you should examine the cellar itself or another storage place. If there are traces of the pest, then the storehouse and containers must be disinfected with whitewashing quicklime or fumigants (the means by which they fumigate the premises). Experts recommend the use of a smoke bomb for a cellar from the moth “Gamma” or “FAS”.
Significantly reduce crop losses by spraying infected potatoes in the cellar with the Entobacterin microbiological solution. It is effective against flying insects, that is, from a butterfly moth, which after processing the premises will lose activity, will not be able to lay eggs in tubers.
By the way, keep in mind, at a temperature of 3-5 ° C, this pest does not develop, it dies, so it is better to store the crop in the cellar in such conditions.
At the moment, in Russia most often the potato crop spoils the potato moth. Measures to control this insect are not as simple as it might seem.
- Plant healthy seeds at the right depth.
- Do not start planting potatoes - often spud higher.
- Time to destroy the tops before harvesting if moth was found on the field.
- More often sort through potatoes in the cellar to remove infected tubers.
- Treat storages, cellar, infected tubers every 10-12 days with recommended drugs.
These actions will protect the crop from potato moths.
Watch a video that will help you identify the pest, find out what it looks like: