Pests and Diseases of Cucumber: ecological treatments

Good Agrohuerters, today we are going to see what the cucumber pests and diseases are, since we recently talked about how to grow cucumbers. As you already know, cucumber is from the same family as melon, zucchini and watermelon among others. Therefore, it will be affected by pests and diseases very similar to all of them.

Cucumber pests: spider webs, galleries in the leaves,…

The most common cucumber pests and diseases are:

red spider on cucumber

The Red Spider (Tretanychus urticae) is a type of mite, which attacks almost all types of horticultural plants. It is recognized because a kind of tiny red dots can be seen on the leaves and cobwebs. The symptoms that the plant presents are the loss of the color of the leaves, in most cases covered with cobwebs or silk. If the attack is very strong, the leaves can dry out and the plant can die.

To avoid this, it is necessary to maintain the environmental humidity, this can be achieved with sprinkler irrigation, in case they are in an area covered by misting, shading nets or ventilation. Try not to overdo the subscriber and carry out the irrigations correctly. In the event that the pest is very invasive, the use of sulfur sprinkled in the early hours of the morning and treatments with vinegar and soap or with nettle extract is recommended.

Cucumber leafminer fly

The attack is carried out by the larvae feeding on the leaves, they create galleries that look like small paths. This pest is identified because the areas of the galleries are very pale yellow and if we get closer it is likely that we will find the pupa (it would be like a kind of cottony tube inside which the larva transforms into an adult). Due to the weakening of the leaves, other diseases such as fungi can appear.

To prevent, it is best to buy healthy seeds or seedlings, use the yellow traps to detect if there are adult insects, if we see affected leaves remove them immediately. For its treatment, it is recommended to release its natural enemies such as Dacnusa sibirica. Or spray with Neem in the late afternoon.

cucumber diseases

Cucumber fruit sucking

It is a very common physiopathy in cucumber, which occurs due to lack of water or very sudden changes in temperature or humidity. The fruits grow with deformations, and very thin, in addition they usually do not finish developing in conditions. Therefore, they are not usually consumed.

We can only do prevention by avoiding these sudden changes in temperature, and by watering properly, never in deficit.

White collar rot (Sclerotinia sclerotiorum)

This disease is caused by the fungus (Sclerotinia). The attack can be on the roots or on the leaves, in this case we can see small black spheres, rotting occurs in a few days that appears with white cottony areas. It reproduces in conditions of high humidity and not very high temperatures around 20ºC and quickly spreads through the plant, causing death.

To avoid the appearance of this fungus, a correct crop rotation must be carried out, facilitating ventilation during cultivation, in crops with soil in it, preparation work must be done for the next crop. It is advisable not to pay in excess and to use drip irrigation to avoid waterlogging.

The plants that we can see very affected it is recommended to destroy them, use ecological fungicides or incorporate with the irrigation other fungi that feed on the one that has colonized the plants such as (Trichoderma or Coniothyrium spp) these can be purchased in specialized gardening stores.

Ironing of the fruits

It is an alteration or physiopathy, which usually occurs frequently in summer vegetables; because it occurs due to direct exposure of the fruit to the sun, sometimes UV rays negatively affect the skin of the fruit causing burns. One of the remedies is to shade the crop in the middle of the day or place the crop in a place where there are others that provide some shade.

Cucumber mosaic virus

In general, they are usually transmitted by insects such as aphids and thrips, or are found dormant in the seeds. The symptoms that the plant presents are dwarfism, yellow spots on the leaves that roll up on themselves, and sometimes deformations in the fruits that are normally discarded due to their poor quality. One of the viruses that most affects cucumbers is CMV (Cucumber Mosaic Virus).

With virus cases there is no treatment, so you have to prevent as much as possible, using barrier crops such as sorghum, quickly treat cases of aphids if you notice that they appear. Make crop rotations and most importantly buy healthy seeds or seedlings.

References

1. TATLIOGLU, T. (1993). 13 – Cucumber: Cucumis sativus L. Editor(s): G. KALLOO, BO BERGH, Genetic Improvement of Vegetable Crops, Pergamon, 197-234.
2. Mariod, A., Saeed, M., Hussein, I. (2017). Chapter 16 – Cucumis sativus Cucumber, Editor(s): Abdalbasit Adam Mariod, Mohamed Elwathig Saeed Mirghani, Ismail Hussein, Unconventional Oilseeds and Oil Sources, Academic Press, 89-94.
3. Mariod, A., Saeed, M., Hussein, I. (2017). Chapter 17 – Cucumis prophetarum Globe Cucumber or Wild Cucumber. Editor(s): Abdalbasit Adam Mariod, Mohamed Elwathig Saeed Mirghani, Ismail Hussein. Unconventional Oilseeds and Oil Sources, Academic Press, 95-98.

Agrohuerters I hope that with these tips on how to prevent these most common pests and diseases, you will achieve a very healthy cucumber plantation. Regards and until next time!