Why do zucchini get rotten fruit? Causes and control methods

Zucchini is a common vegetable in our daily lives, and one that many people like. During the process of growing zucchini, rotten fruit often occurs, which seriously affects the yield and quality of zucchini and reduces farmers' income. So how should rotten fruit in zucchini be controlled? Let's take a look at the detailed introduction below.

1. Gray mold

Gray mold harms flowers, fruit, stems, leaves and other parts. The pathogen first invades from withered female flowers. In the early stage, the petals appear water-soaked or water-soaked-like, then gradually soften and rot, accompanied by a grayish-brown mold layer. This causes the petals to rot and fall off, and then the pathogen develops toward the young fruit. The affected part gradually softens and rots, and a large amount of gray mold appears. When the disease occurs on the stem, gray lesions appear, and after encircling the stem, they cause the stem to break.

Control method: For gray mold, iprodione can be used preventively when dipping flowers. When the disease occurs, iprodione or vinclozolin can be sprayed for development, or smoke fumigation with a nuclear net smoke agent can be used for control.

2. Sclerotinia rot

This disease mainly harms the fruit and stems and vines. When the fruit is infected, it first shows water-soaked rot, and afterward white mycelium grows at the affected area, and the mycelium spreads black sclerotia. When the stems and vines are infected, they initially appear water-soaked, the diseased part turns brown, and later white and black sclerotia gradually grow. The stems and leaves above the diseased part die.

Control method: When planting, this disease requires clearing the field and disinfecting the soil to reduce the source of pathogenic bacteria. The control method is similar to that for gray mold.

3. Fruit rot

Fruit rot, as the name implies, is a disease that harms the fruit. The pathogen usually infects from the flower base and wounds. In the early stage, it appears water-soaked, then gradually turns brown and soft-rots. In the later stage, white or pink mold-like substances appear at the affected area, and finally the entire zucchini rots. The pathogen of this disease overwinters in the soil, and the fruit is highly prone to infection when it contacts the soil. It is also highly prone to infection under high humidity and improper water and fertilizer management that causes fruit cracking.

Control method: To control fruit rot, first adopt high-ridge plastic film mulching cultivation technology, increase the application of organic fertilizer, enhance plant immunity, reduce wounds, and promptly remove diseased fruit when found. In the early stage of the disease, sprays such as copper sulfate, Sandofan, and metalaxyl copper can be used for control, or carbendazim can be used for root drenching.

4. Soft rot

When soft rot occurs, it appears brown and water-soaked, then quickly softens, and the inside of the affected area rots. This disease spreads extremely quickly. After the diseased zucchini rots, it gives off a foul odor, but there is no mold fuzz. This is the biggest difference from other diseases. It is a bacterial disease, spread through rain, watering, and insects, and is prone to occur in environments with poor field ventilation and relatively high humidity.

Control method: When the disease occurs, copper-based preparations can be used for control, such as rosin acid copper emulsifiable concentrate, copper fatty acid amide, and copper hydroxide wettable powder, sprayed once every 7-10 days for control, 2-3 times in a row, with good results.

The above is an introduction to the causes of rotten fruit in zucchini and control methods. We hope it can help you. If you want to learn more related knowledge, please follow us.