Pests and diseases of melons: what they are and how to deal with them

Like all cultivated plants, melons are susceptible to attack by pests and various diseases caused by bacteria, viruses, and fungi. The main sources of infections are contaminated seeds, weeds, and soil. Timely detection of signs of plant damage and adequate treatment will not only preserve the future harvest, but also increase it.

Melon diseases

Melons are susceptible to diseases characteristic of all melons. The crop becomes infected through weeds or the remains of other plants, soil, and water. Infections are spread by insect pests, wind, rodents and humans themselves on contaminated tools.

Powdery mildew

The disease manifests itself as a small white coating on the leaves, stems, and petioles, which causes the affected parts of the bushes to darken and dry out. Hot and dry weather is the main reason for the spread of powdery mildew. It is provoked by the wind and insects that transfer parts of infected plants to healthy ones.

Downy mildew

Downy mildew, or downy mildew, is a fungal disease accompanied by the appearance of bright yellow-green spots on the upper side of the leaves. Subsequently, they become wet, acquire a brownish tint, and dry out. Sporangia form on the undersides of the leaves, which release fungal spores that are carried by wind and insects to healthy melons.

Reference! The difference between powdery mildew and peronosporosis is the presence of sporangia on the back of the leaves.

Ascochyta blight

With ascochyta blight, the fungus affects the root collar. The first symptoms are pale spots that increase until they cover the entire root collar. The leaves, stem and fruits themselves become soft and black, and then dry out.

As a result, the stem is destroyed, and ripened spores are spread by wind and insects to healthy melons. The main causes of the disease are high air humidity and low soil temperature.

Fusarium

Fusarium wilt is practically asymptomatic or appears as gray spots on leaves and stems. The bushes dry out in a period of 2 to 10 days. Fruits ripened on diseased plants lose their juiciness, aroma, and keeping quality. The causative agents of the disease live not only on plant remains, but also in the soil and on the seeds of dead crops.

Root rot

Weakened melons are susceptible to root rot. In young plants, the roots and stems become brown, thin, then wither and die. Ripe melons have leaves that turn yellow. At the fruiting stage, melons are not mature or they rot: the flesh of pumpkins with fungus becomes covered with brown spots inside.

Anthracnose

With anthracnose, or copperhead, the leaves become covered with brown or pink round spots, which increase over time. As a result, holes form at the site of the spots, and the leaves curl into loops, which then become thin and break. The fruits of diseased plants become deformed and become rotten inside. The pulp becomes covered with brown or red rot.

Septoria

Septoria, or white spot, is caused by fungal organisms. White round spots form on the affected plants. Over time, the central parts of the spots darken, which indicates the fungus is ready to spray spores.The disease develops in damp, rainy weather, when spores along with liquid fall on healthy bushes. The pathogen persists in the soil for a long time.

Cucumber mosaic

This viral disease manifests itself in the form of green-yellow mosaic spots on the leaves that become deformed and curled. The fruits become covered with warts, cracks appear at the base of the stems, and the growth of the bushes slows down. The virus persists on plant roots and is transmitted by melon aphids.

Gray mold

Fungal disease is common among young melons. The ovaries of affected plants become watery, covered with mold and fungus, which persists in the soil for 2-3 years. Favorable conditions for the disease are humid weather with a temperature of +15°C (at higher temperatures the fungus spreads more slowly).

Cladosporiosis

Cladosporiosis, or olive spot, is a fungal disease. The leaves of the crop become covered with dark round spots that grow until they occupy the entire surface. The fruits become covered with jelly-like drops that turn into lacerations. Sudden temperature changes and abundant or irregular watering contribute to the development of cladosporiosis.

Bacteriosis

Initially, bacterial spotting affects leaves and stems, then spreads to fruits. The main symptoms are medium-sized brownish-brown greasy spots on plants, the formation of drops with cloudy liquid on the reverse sides of leaves on rainy days, and glass-like ovaries. Bacteriosis actively develops under high humidity and high temperatures.

Treatment

Treatment of melons begins when the first symptoms appear. This will save the plantings from further spread of infection:

• powdery mildew - bushes are treated with an 80% sulfur solution at intervals of 8–10 days;
• peronosporosis - use a urea solution (1 g per 1 liter of water) or 1% Bordeaux mixture (1 liter per 10 m2), every 10 days use “Topaz” or “Oxychom”;
• ascochyta blight - use a 1% solution of Bordeaux mixture, add potassium fertilizers, and disinfect the soil;
• fusarium - isolate and destroy affected plants from healthy ones (the latter are sprayed with potassium phosphate solution: 5 g per 10 liters of water);
• root rot - the affected plants are removed, the soil is regularly loosened, the bushes are not over-watered;
• anthracnose, septoria - leaves and fruits are sprayed with a 1% solution of Bordeaux mixture or sulfur powder;
• cucumber mosaic, cladosporiosis, bacteriosis - diseased plants are destroyed;
• gray mold - bushes are treated with a solution of 1 g of zinc sulfate, 10 g of urea, 2 g of copper sulfate and 10 liters of water.

Prevention methods

To prevent crops from diseases, both universal methods and methods for preventing specific diseases are used. To increase the general immunity of melons, the soil is regularly weeded to remove weeds, crop rotation rules are followed, and dead and infected fruits and bushes are destroyed.

Prophylaxis against specific diseases is carried out:

• against powdery mildew, root rot, fusarium, plants are systematically watered;
• after harvesting, plow the soil: this saves future plantings from peronospora, ascochyta, fusarium (against septoria, the soil is dug especially deeply, up to 25–30 cm);
• heat treat the seeds before planting with warm water (+45°C): this protects the seedlings from peronosporosis and cucumber mosaic;
• melons are fed with potassium fertilizers to prevent ascochyta blight;
• the seeds are treated before planting: against peronosporosis and other fungal diseases, they are soaked in a 1% solution of potassium permanganate for 20 minutes or in a solution of “Fitosporin-M” (1.5 g/l), against fusarium - in a 0.1% solution “Baktofit” for 3 hours, for root rot use a 40% formaldehyde solution for 5 minutes, for bacteriosis - a solution of potassium permanganate, aloe juice or hot water.

Pests

Melon plantings are threatened by many pests that are easily recognized when they appear on plants:

• melon aphid - collects on the back side of the leaves, which then turn yellow, curl, and die;
• spider mite - lives on the back of the leaves, they turn yellow and become covered with red spots. The mite leaves a web, sucks juice from plants, which leads to their death;
• wireworm larva - holes appear on the fruits and stems through which insects eat the pulp and destroy the stem;
• caterpillar of a gnawing cutworm - the entire stem is covered with bite marks;
• melon fly - adults fly over melons, holes appear in the fruits, which have been gnawed by larvae, the pests carry viral and fungal diseases.

Fighting methods

To combat insects, both traditional methods and chemicals are used:

Reference! To destroy wireworm eggs, it is enough to dig up the soil so that the pests are exposed to the light. The sun's rays will dry them out.

Tips and tricks

Tips from experienced farmers will help protect the crop and increase the harvest:

• constantly care for melons: weed the beds, water regularly, spray the bushes against pests, remove weeds and infected fruits;
• to implement proper crop rotation after melon, sow the soil with annual and perennial grasses;
• to combat wireworm larvae and cutworm caterpillars, when planting a crop, add 1 tsp to each hole. ground eggshells.

Read also:

Review of Chinese Bitter Melon (Momordica).

What is good about Kassaba melon, how to choose and grow it.

Delicious recipes for melon preparations for the winter - you'll lick your fingers!

Conclusion

The best ways to combat plant diseases are through proper care and prevention.To prevent most diseases, crop rotation is observed, the beds are weeded from weeds, dead and diseased plants are removed, and seeds are disinfected before planting. Special preparations are used against pests to destroy insect-infested bushes.