Any gardener is faced with such a thing as leaf chlorosis.
Plant disease is manifested in unnatural (off-season) yellowing and falling of leaves. The cause of the disease lies in a violation of the formation of chlorophyll, which means a decrease in the activity of photosynthesis. In this case, the leaves can lose color not only completely, but also partially, and new (young) shoots and leaves noticeably become smaller. The edges of leaf blades are often twisted, the buds formed (on the flowers) are deformed. The tops of the shoots are either very weak or shrunken.
Chlorosis of leaves can be infectious (possibly infection of other plants) and non-infectious (occurring in violation of agricultural technology). Consider chlorosis in more detail.
To begin with - chlorosis of leaves (photos of infected plants), where, as an example, vine bushes:
Infectious grape leaf chlorosis
Gardeners call it "leaf spot" and "yellow mosaic." Refers to viral diseases of infectious degeneration. For the vine, the disease poses a very serious danger (leaf curl, viral short stub, plant death). Bushes exposed to viral chlorosis become yellow-lemon. Leaf veins, unlike ordinary chlorosis, become discolored. With short knots, the size of the internodes decreases significantly, the leaves become smaller, the formation of stepsons increases significantly. In a mosaic , grape leaves, discolored along with the veins, are wrinkled and wrapped (curled).
Control measures, prevention
The infected plant is immediately uprooted, the soil is etched with dichloroethane (vat residues). A careful choice of planting material can prevent the occurrence and spread of chlorosis (the vine, which is planned to be planted in the future, is harvested from bushes that are absolutely healthy and strong). To bookmark vineyards, select areas free of nematodes, which are the main carriers of the virus. Areas where virus outbreaks have previously been reported are recommended to be seeded with cereals (up to six consecutive years) that nematodes do not feed on.
Common chlorosis (non-infectious)
Somewhat different from infectious. Here, yellowing of the leaves is also observed, but the veins remain green. At the same time, the overall growth of the plant is markedly inhibited, at the same time quite abundant growths appear (mainly the lower parts of the bush). The reason for the appearance of non-infectious chlorosis lies in the disturbed metabolism of the plant, associated with excess moisture, a lot of lime, an alkaline soil reaction, but more often with a lack of iron.
Control measures, prevention
With an excess of lime, ammonium sulfate (3 kg under a grape bush) is added. Vaccinations on stocks resistant to calcareous soil are recommended (41-B Chasla on Berlandieri has proven itself most). Excess moisture can be combated by deep digging (excess water evaporates faster). If rainfall is high in your area, initially pay attention to varieties resistant to chlorosis.
Additionally recommended:
- autumn introduction of vitriol in the soil (directly under the bush, 500 grams);
- spraying with vitriol (0.5%) in the spring, during the growing season (instead of vitriol, you can use iron chelate, which is even better);
- the introduction of complex dressings (micro-, macro-) with the content of manganese, iron, zinc.