Tetranychus urticae
Appearance:
The plant mite is difficult to see with the naked eye. Its size is only about 0.3 to 0.6 mm and depends on its diet. The plant mite is elliptical in shape. In the first larval stage it is 6-legged, in all other stages of development 8-legged. Their coloring varies – during the winter they are orange to vermilion, the rest of the time they are pale to light green.
Reproduction:
The female plant mites lay around 50 to 100 eggs over the course of their two to five-week life. These are laid in small groups on the underside of the leaf near the center. The eggs are pearly white, spherical and have a diameter of approx. 0.13 mm.
The entire development from egg to full insect can be completed after just 8 days, but is strongly dependent on temperature. Plant mites prefer warm, dry summer and fall weather.
Plant mites feed on plant cell sap in all life stages.
Way of life:
Plant mites infest a variety of crops, such as vines, peas, beans, cucumbers, potatoes, hops, strawberries, sunflowers and fruit trees. Plant mites often occur in greenhouses.
They cover infested leaves with a fine web. This is initially characterized by small, light, yellowish-white spots. If the infestation is more severe, the leaf color changes from green to grey or even copper-brown.
