Cucumber Anthracnose

2024 Author: Gavin MacAdam | [email protected]. Last modified: 2023-12-16 13:38

Anthracnose is capable of infecting cucumbers at any stage of their growth and development. Cucumbers grown in film structures and in the field are especially affected by it. And in the southern regions, anthracnose easily attacks cucumbers grown in the open field. By the way, in addition to cucumbers, this harmful ailment can also affect a number of other pumpkin crops - melons, watermelons, loofah, and a little less often - pumpkin. In some years, this attack can lead to the loss of a good half of the crop, so it is imperative to fight it

A few words about the disease

You can notice the manifestations of anthracnose even at the stage of growing cucumber seedlings - the formation of brownish slightly depressed spots begins on the root collars of plants. However, most often the disease attacks the leaf blades, which are covered with specks of brown or yellow. In most cases, the specks are located along the edges of the leaf blades. And if the defeat is too strong, they can merge. As a rule, such spots are characterized by completely different sizes. Sometimes they can rupture, forming numerous slit-like holes. Infected leaflets are almost always very poorly functioning.

Stem lesions are usually identical to leaf lesions. Sick stems often break off. The infection spreads quickly enough throughout the stem, and as a result, the plants begin to die.

On the affected fruits, oblong, depressed specks of light brown color and a wide variety of sizes are formed. The mycelium often penetrates about 3-4 mm deep into the tissues.

On all infected parts of cucumbers, fungal sporulation develops, which looks like numerous pale pink pads, merging into a continuous bloom or located in concentric circles.

The causative agent of cucumber anthracnose is a harmful fungus that develops in a very wide temperature range - from four to thirty degrees. At the same time, the air humidity should be high enough - about 90 - 98%. And the incubation period lasts an average of four to seven days.

The pathogen persists either in the form of microsclerotia in plant remains, or in the form of mycelium in seeds collected from diseased fruits.

Arthropod insects and water play an important role in the spread of destructive misfortune - during watering, it washes away conidia, thereby provoking their lightning-fast dispersal over growing crops.

How to fight

The most effective preventive measures against cucumber anthracnose are the elimination of post-harvest residues, crop rotation in crop rotation, deep autumn plowing and pre-sowing seed dressing. Most often, "Tiram" is used as a dressing agent. You can soak the seeds before sowing and in the "Immunocytophyte" solution. And infected seedlings should be discarded in a timely manner.

It is necessary to systematically disinfect greenhouse structures, as well as the soil in them. It will also be useful to improve the soil through the introduction of organic fertilizers and biological products.

To stop the development of anthracnose, it is recommended to reduce the air humidity to at least sixty percent. Also, cucumber plantings begin to be sprayed with fungicides. The drugs "Quadris" and "Abiga-Peak" help to achieve a good effect. Treatments with sulfur preparations, one percent Bordeaux mixture and a suspension of copper oxychloride (0.3%) help very well. And to achieve the best results, shedding under the root of adult crops and infected seedlings with a solution of Bordeaux mixture at a concentration of 0.5 - 1% helps. First, the soil is poured abundantly with water, and then with the help of a watering can, watering is carried out with the prepared preparation, and only the roots and bases of the stalks are watered. As a rule, 0.5 - 1 liter of this composition is consumed for each plant.