How to identify disease of cucumbers on the leaves?
For cucumbers one of the earliest and most accurate signals about the diseases is to change the leaves. The rate of development of illnesses in this culture is that the farmer is almost impossible prospustit initial stage in which the plant will be the most effective treatment.
Askohitoz
The most actively affects greenhouse cucumbers in the time of fruiting. Until the outbreak of the infection may be a fungus is in a stage of hibernation in the soil or on the stems of plants.
The first sign is a light-gray spots on the edge of the leaf, then spreading them entirely and complements the black patches (so looks like body containing spores of the fungus).
Peronosporosis, or downy mildew
Usually it occurs with the cooling nights and an increase in precipitation in July-August. First, at the top of the leaves appear yellow small spots, resembling "freckles", and at the bottom - grayish-purple patina.
Spores are almost invisible - scattered black dots. spots grow and then go into the smoky-brown color, and the leaves are deformed.
Fusarium wilt
Most likely during the flowering and early fruiting. It begins with the fact that the leaves wilt, just fade in the afternoon and come back to normal state at night.
By the time the ovaries, zhely leaves turn color and start to dry near the stem.
spider mite
The appearance is most likely in the dry hot weather. On top of the leaves appear bright spots, then often turns into a pattern similar to marble.
The bottom leaves are covered with the finest gossamer milky, indicating that the pest started kidnapping chlorophyll from plants by sucking its juice.
anthracnose
Equally distributed among planted in open ground and in greenhouses, favorable conditions - heat and humidity. The first sign is rusty spots on the edges of the leaves or between the veins. The size ranges from a few millimeters to 4 cm.
The defeat leaves often begins with the part that is closer to the ground. Later spots grow and the leaves turn yellow in its entirety.
powdery mildew
It has been active since the mid to late summer. The primary white coating on the underside of leaves barely noticeable. Next to it are added to round white spots on the top, soon darkening.
The leaves are also deformed - dry and become wavy shape.