This is one of the most known diseases and severe, since if the environmental conditions are favorable, You can attack all green plant organs, I can lose a significant part of the crop.
It is caused by a fungus and appears in regions of warm and humid weather during the vegetative growth.
1) Sheet: Typical oil stains are distinguished in the beam, corresponding on the underside with a whitish fuzz.
2) In buds and branches: Outbreaks curve, covering a whitish fuzz, they can dry out and fall if the attack is strong.
3) In Bunches: Grains can be initially or subsequently attacked. In late attacks, no clusters are covered with a white fuzz but turn brown.
The activity of the fungus starts in spring, who has spent all winter on fallen leaves down, outputting, to mobile zoospores, that I slide down the host plant infection spreading.
This situation is repeated as the humidity, until autumn, the fungus enter into a resting phase.
The following conditions are ideal for the activity of the fungus:
· Length of outbreak 10 cm.
· Drop a rain 10 mm minimum.
· Exceeding 10 º C temperature.
– Chemical control of downy mildew should be performed according to the climatic conditions that favor disease. The protection strategy is to treat in a timely manner to prevent the development of disease.
– In low damp situations prone to mists and sprays atmosphere, is more favorable disease required by various treatments.