Causes and control methods of leek leaf rot

In winter and spring, both leek growers and consumers are extremely afraid of encountering rotten leaves of leek. For growers, once they encounter rotten leaves of leek, the yield will be reduced and the harvest will be lost if it is heavy. So what is the reason for the rotten leaves of leek? Let's get to know it with the editor.

First, the cause of rotten leaves of leek

1. Grey mold

There are mainly three types of expression, white spot, dry tip type and wet rot type, in which white spot type and dry tip type are often mixed, and there are oval to fusiform white spots on the leaf surface or leaf edge, which develop downward at night, and only dry shrinkage of the leaf in the middle and later stage. Wet rot is at high temperature, the leaves produce white spots, the leaves initially show water stains, and soon there will be a gray mildew layer, causing the leaves to rot.

2. Epidemic disease

It mainly infects the middle and lower part of the leaf. After the damage, the disease spot is dark green, the disease part overflows, the leaf turns yellow and wilts, the disease spot is soft rot in wet weather, there is white frost layer, when the leaf sheath is damaged, it shows brown water immersion disease spot, soft rot, leaf peeling, and the bulb and root show soft rot, which affects the absorption and accumulation of nutrients.

3. Cotton blight

The leaves initially showed dark green water stain disease spots, when the disease spots extended half of the leaves, the leaves showed yellow wilt and droop, and there were milk cotton flocculent hyphae when the humidity was high.

4. Yellow leaf disease

The disease spot expands from the leaf tip and leaf edge to the midrib, causing the leaves to turn yellow longitudinally, yellowish brown at first and dark yellow in the later stage, which mainly harms the outer leaves of leek.

5. Soft rot

This is a bacterial disease, the main harm to stems and leaves, the appearance of gray-white translucent, disease spots gradually soften and rot, will exudate mucus, with stench, serious lodging and death.

II. Prevention and control methods

First of all, we should choose strong disease resistance, clean up the field after planting, clean up all the diseased bodies, bury them deeply or burn them, and reduce the number of pathogens. Fumigation or dust control can be used before sowing, or 250 grams of thiabendazole can be used per mu, lit and closed greenhouse, fumigated overnight, or more than 6.5% of bacteria per mu and 1 kg of cardamole dust can be sprayed once every 7 days. Before the onset of the disease, strychnine can be sprayed every 7-10 days. After the disease is found, base spraying such as humeiling and prohydantoin should be sprayed once every other week for 2-3 consecutive times.

The above is the introduction of the causes and control methods of rotten leaves of leek. I hope it can help you. If you want to know more about it, please follow us.