Root aphid - secretive pest of agricultural and ornamental crops

Root aphid is a tiny pest of a narrow specialization, affecting small roots of plants. It is common for each species to live exclusively on one culture. So beetroot prefers sugar beets, Phylloxera vastatrix - vine, Pemphigus filaginis dauci settles on carrots, white on the roots of ornamental plants. Despite the various objects of parasitism, the appearance and lifestyle of root aphids are the same, as are the ways to deal with them.

On a note! Previously, root aphids were systematized as a separate independent earthen species. However, as a result of numerous studies and observations, it was revealed that the underground generation appears as a result of migration of insects from the aerial parts of plants to the roots of the same plantation.

Biological features of root aphids

The number of aphid species is close to 30 thousand. All of them are united by small dimensions, a piercing-sucking mouth apparatus, and symptoms of a lesion.

Pest portrait

What aphid looks like depends on the stage of development of a generation. From 10 to 15 generations of offspring and a life cycle are possible per year, their appearance is different:

• The eggs are oval in black with a shiny sheen.
• In spring, the founder of the colony appears from the egg. It is characterized by the absence of wings, a plump little body on short legs. There are short antennae on the head. Color from milky white, yellow to olive green. The root aphid of carrots has a reddish tinge of the body.
• A wingless asexual virgin is very similar to the founder, but has a flattened abdomen. The length of the ovoid pear-shaped body does not exceed 2.6 mm, reaches a width of 1.4 mm. Color more often yellow or green shades. The body is covered with sparse hairs and a waxy coating. Three facet eyes of red or black color. Legs, antennae stand out with a dark brown color. In summer virgins, the antennae are five-membered, between them 2 rare hairs are visible. In individuals that remain for the winter, the mustache consists of 6 segments.
  
• The size of the larvae of the first age does not reach 1 mm. The yellow or greenish body is elongated. Waxy coating is gray. At the end of the four-segmented antenna, 5 setae are located.
• Strips are distinguished by the presence of wings, an ellipsoidal body, the length of which is 2.5 mm. The abdomen is yellowish with a characteristic gray waxing. Paws are six-segmented, antennae brown.
• Normal females and males are devoid of wings. Outwardly similar to larvae. Females are larger than males, the body color is saturated with green shades. Males are yellow.

On a note! Root aphid parasitizes not only on crops, but also feels at ease in flowerpots with indoor plants. Aphids can be distinguished from other pests by a bundle of wax threads that crown the end of the body and are the secret of glandular groups.

Lifestyle & Reproduction

Flightless females winter in the soil, vegetable stores, along roadsides, in the roots of weeds.Individuals can take refuge from adverse weather conditions at a depth of 40-60 cm. There are cases when wintering females were found to a depth of one meter.

With the onset of warmth, the female founders begin to fulfill their mission. They do not feed on anything, they hatch the first generation of larvae, which are called vagabonds and die immediately.

Interesting! If autumn was dry and warm, the fecundity of spring wingless females is higher.

The activity of strollers is noted when the soil warms up to 10-12 ° C. Some individuals remain on the same roots where hatching occurred. Others climb to the surface. As a rule, this happens in the last decades of April, early May. Vagabonds are very mobile and actively begin resettlement. Weeds are often the primary source of nutrition. Such as quinoa, white gauze.

Subsequently, insects, becoming larvae of the first age, migrate to cultivated plants. The developmental stage from the larva to the adult female lasts no more than 2 weeks. Under favorable conditions, and even less - 8 days.

On a note! The first foci of settlement of root aphids are formed mainly along the edges of the field. With an increase in the number of pests, infection becomes widespread.

During the season, 10-13 generations of offspring occur. The peak of reproduction occurs in July – August. In sunny dry weather, the process continues in September and October. Aphids with wings, called strips, appear in August mainly in the surface soil layer. They reproduce amphigonic males and females. This generation practically does no harm, as it flies to poplars. The laid eggs on the bark of trees die in the winter. The role of the strips in the biological chain is not fully understood.
Normal females and males lay their eggs in the soil in September. Of them, the next year, the founders appear. Some eggs are moved on root crops to storage, where a new cycle of development of the root aphid population takes place.

What is dangerous root aphid

Root aphids, like their relatives, use plant nutrients as a source of nutrition. Only they prefer the underground parts - fibrous, thin lateral roots. Damage is fraught with withering of the fetus, and subsequently the drying of the leaves and the plant itself.

Especially exacerbates the situation is the lack of moisture. In dry periods, plants easily undergo the appearance of rot, and are easily removed from the earth. Weakened seedlings become vulnerable to diseases, are not able to resist other pests.

On a note! The percentage yield loss is approximately 5% in beet fields. Infected root crops become carriers of aphids in vegetable stores.

Signs of infection

To determine what the root aphid parasitizes on a culture by the following signs:

• underdevelopment, deformation of the root crop;
• yellowing foliage;
• growth lag.

In the presence of such signs and the absence of other pests, carefully dig one plant and carefully examine its root system for root aphids.

Root aphids on carrots appear much less frequently than on beets, roses, fuchsia, grapes, bulbous pasture crops, and cereals. The reason for its appearance is often ants that grow and protect aphids. The most common root aphid was on beet crops. The main factors for the spread of aphids include improper crop rotation, planting in infected soil.

How to deal with root aphids

Due to the localization of the pest, it is much more difficult to deal with it than with the leaf form. However, this does not mean that it is impossible to defeat a small insect. First of all, it is worth alternating monocotyledonous and dicotyledonous plants annually. In no case, do not plant beets in the same place.

In addition to observing crop rotation, measures to combat root aphids include the following measures:

• thorough cleaning of root crops, plant residues;
• deep plowing of the soil in the autumn period;
• watering and feeding plants during the growing season;
• cleaning the site of weeds with subsequent disposal, burning;
• adding wood ash to the holes when planting plants;
• in indoor plants, the pot is disinfected and the soil is replaced.

To destroy the root aphids, biological preparations are used: Fufanon, Akarin, Boverin, Guapsin. Of the more potent chemicals used are “Karate”, “Sharpei”, “Fas”, “Decis”, “Inta-Vir”.