Why is bacterial pith necrosis easy to occur in tomato?

Bacterial pith necrosis is an important disease in the process of tomato planting, which seriously affects the yield and quality of tomato. Sometimes it will even lead to the extinction of the whole shed, why is bacterial pulp necrosis easy to occur? Shall we take a look at it together?

1. Environmental factors

High humidity is a basic condition for the occurrence of bacterial pith necrosis of tomatoes. During a period of time after the tomatoes planted in protected areas in winter could not be ventilated or watered normally, the occurrence of diseases caused by humidity in the greenhouse created conditions.

2. Wound infection

The bacterial pith necrosis of tomato is mainly infected by the wound on the stalk. Many farmers do not pay attention to the external environment when they carry out agricultural operations, such as pruning and branching after continuous cloudy days or watering, and the resulting wound provides a channel for the infection of bacteria.

3. the disease of overgrown plants with vigorous growth is serious.

The stem water content of overgrown plants is high, on the one hand, it is not conducive to wound healing bacteria more easily to invade, on the other hand, it is convenient for bacteria to spread and develop rapidly in the pith.

Symptom expression

Tomato bacterial pith necrosis is a systemic infection disease, which mainly damages stems, branches, leaves and fruits, and mostly occurs in the fruiting period.

The young leaves fade in the early stage of the disease, and the upper part of the plant fades and wilts in severe cases.

With the necrosis of the lower stem, brown to dark brown spots appeared on the surface of the diseased stem, and the outside hardened. The pith of the diseased stem turned black or necrotic in the longitudinal section.

Dry shrinkage, hollow, browning of vascular bundles, adventitious roots may occur where lesions occur in the pulp.

When the lower stem is infected in production, it often causes death of the whole plant.

When the humidity is high, the bacterial pus overflows from the stem wound and adventitious root, which is different from canker.

Prevention and cure measures

Reasonable close planting, strengthen ventilation and reduce humidity in the shed, especially in continuous overcast weather or just after watering.

Avoid operations such as pruning and forking in continuous overcast weather or just after watering and high humidity in the shed to reduce stem wounds. Usually, bacterial agents should be sprayed in time after pruning and leafing.

Strengthen management to avoid excessive growth of plants, especially when the stem of the plant is about 40 cm, fertilizer and water should be properly controlled, especially the amount of nitrogen fertilizer should be reduced.

After it was found that tomato was susceptible, it was necessary to spray 500 times of Wanjia liquid and 750 times of Yiwei solution in time for root irrigation treatment.