So I want to reassure you, to say that this disease is no longer, but it would be untrue. No one can be sure that it will not appear on his own beds.
This disease was discovered in 1965 on a strawberry and papaya plantation in Australia, and described in 1968. Called Anthracnose, or black spot. This disease is caused by mushrooms Colletotrichum acutatum Simmonds. During this time, the pathogen seemed not just walking on the planet, and flew on airplanes. Because he now “lives” on all continents, and the closest places of his deployment – Bulgaria, Finland, Latvia, Lithuania, Poland, China and Turkey.
The disease therefore quickly spread around the world, that at first it flows without symptoms, outwardly does not manifest itself: the plants look healthy, but all the organs are affected. It is believed that the main source of infection was the uterine plantations of California, from which seedlings of repairing and neutral-day strawberries were transported around the world.
Signs of Anthracnose
On the antennae and the upper part of the petioles, on which the new leaves unfolded, there are oblong depressed ulcers. First they are small, red-brown, and then turn black. Gradually, the ulcers form a ring around the antennae or petiole, and they dry up. On leaves a lot of spots up to 2 mm: they are initially light brown and later become black. Over time, the spots also merge into large spots, and the leaf dies. Sometimes on the leaf blade, along the veins, may appear sector of the affected tissue (form similar to the letter V).
The flowers are infected from the leaves and antennae, take the form of burnt. Through the stamens, the pathogen penetrates into the ovary, and the cups of the fruit become colorless.
Immature berries: one or more depressed spots, their color varies from dark brown to black, diameter to 3 mm. When the berry dries out, brown will get a chocolate shade. Stains can get wet.
The ripe berries: depressed spots with a clearly defined edge, brown-bronze; later the spots turn black, and the rot becomes dry and hard.
Achenes: color changes, they become darker, inside the berry spot cone deepens an inch.
It looks like a fingerprint that was pressed on the berry. If the weather is wet, then on the surface of the berries grow roots salmon-pink (sometimes yellow) – it’s disputes. In dry weather, the berries are simply mummified.
Horns and roots: manifestations are similar to the symptoms of late blight and vertical wilt.
He loves the causative agent of Anthracnose
Can live in the tropics, subtropics, temperate climates. The best temperatures for development are from +25…+28°C, with a relative humidity of 95-100%. If the temperature is below +10°C or above +32°C, then the development of the mycelium stops, because in tropical and subtropical zones, the pathogen quickly dies. In temperate climates can be stored in the soil and plant residues up to 6-9 months, although there is evidence of Finnish phytopathologists to preserve for two years.
How to protect against pathogen
- lay their plantations only from healthy planting material;
- to buy seedlings only from reliable suppliers;
- do not take planting material from friends, do not order in other countries;
- before planting, immerse the seedlings for half an hour in a fungicide solution;
- or warm up for five minutes at a water temperature of +49°C;
- in the period from the beginning of flowering to the beginning of the growth of berries four times to spray fungicides.
Summer residents, attention!
If you notice on your bed suspicious plants, and the origin of the seedlings is unknown to you, then do not be lazy to show them to the specialists of the local plant protection station.
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