Insects that damage the African violet: Root aphids (Rhizoecus)

Root aphids or root lice (Rhizoecus) It is part of the Pseudococcidae family. This fact suggests that root aphids and woolly lice are close relatives, only that in the process of evolution root aphids moved to an underground way of life.

Around 130 species of root aphids are known, but their number is increasing. The species that attacked have come to the attention of scientists more valuable agricultural plant varieties and decorative ones.
Amateurs of decorative plants with soft and juicy tissues can meet with common root aphids (Rhizoecus falcifer Kunckel, cacti are also attacked by Rhizoecus cacticans, and rhizoecus aloes aloy. African violets are usually attacked by blind root aphids (Rhizoecus dianthi) and American root aphids (Rhizoecus americanus).
The root aphid is a polyphagous insect. These parasites prefer dry and loose soil substrates.

The first and main clue that signals the presence Root aphids in African violets is the blue-white sediment on the roots of the plant. The roots seem to be sprinkled with ashes or covered with mold. Many times this mold we find in the form of bulgarasi on the side edges of the potted soil.
The flower will carefully rise from the pot and if you see white-blue spores then the violet is infected. The period of attack is during the growing season, spring to autumn.

Root aphids are more minuscule than woolly lice and can not be seenwith the naked eye. They have a length of 1-2 mm. They have three pairs of legs with which they move easily, less females. Adult females and larvae attack the roots of the plant, most of the aphids are found in the soil substrate of the root region. Only a few of them rise on the root 5-10 mm above the ground level in the pot. This portion of the root is usually covered with a whitish "fluff" that represents the secretions of the root lice.

Females have a round or cylindrical body shape, white or yellowish in color. The body of the larvae is covered with a glossy layer similar to wax. The females are inactive and lay eggs inside a special 'chamber' made up of fibrous sediments. These rooms are found on the edges of the potted soil, in the gaps in the soil or around the roots. At a summary inspection of the soil, these pantries can be easily confused with mold.

Larvae emerging from eggs move through the soil at the end roots to feed. They move easily and can also immigrate in the pots in the vicinity.
Males have a pair of wings of skin color, well formed. Adult males do not feed and their life expectancy is quite short. In many generations during a year males may be missing.
Root lice are one of the feared pests of African violets. The attacked plant develops slowly. The leaves are lifeless. As the root is attacked, the plant loses its turgidity and turns yellow.
Root lice feed on cellular juice from the root of the plant, at the same time it secretes into the root tissues substances that alter the metabolism of the plant. Excrement of root aphids are the ideal food for saprophytic fungi as well. The plant with time dies due to multiple lesions of the root system and fungal and bacterial infections.

In combating lice from the root it is important that diseased plants separate from healthy ones. The immune system of plants to be strengthened with various substances, as well as seaweed preparations.
Effective control of root lice is carried out with the help of neonicotinoid insecticides. The insecticide enters the plant and circulates with the sap of the plant through the entire plant. The most indicated are Actara, Mospilan, Dantop. It is enough for the soil in the pots to be watered with a solution from one of these insecticides.
It is recommended no more than 3 chemical treatments at intervals of 7-10 days.
Unfortunately , there are root lice resistant to Actara. If Actara in a concentration of 1 g / 1-2 l of water will not take effect, the insecticide will change.