Control of round spot root rot of Hawthorn

Round spot root rot is one of the important causes of Hawthorn tree death.

First, the symptoms show that the fibrous root first turns brown and dies, and a reddish-brown round spot occurs around the base of the fibrous root. In severe cases, the lesions fuse and rot as deep as the xylem, resulting in blackening and death of the whole root.

Second, the pathogens causing the disease can live saprophytic life in the soil for a long time. When the root growth of tree planting in the mountain is weak, the pathogen invades the root and becomes sick. The orchard with heavy soil viscosity, heavy salinity, long-term drought and lack of fertilizer, serious soil and water loss, serious annual phenomenon and improper management of the orchard is more serious.

Third, control methods (1) strengthen cultivation management, enhance tree potential and improve disease resistance. Improve orchard drainage and irrigation facilities, so that drought can be irrigated, waterlogging can drain; improve soil structure, prevent soil erosion, conditional orchards can be deeply turned over. Ploughing and weeding and preserving soil moisture in time during the growing season; reasonable pruning to adjust the amount of fruit of the tree to avoid the phenomenon of big and small years; orchards with poor fertility should adopt a variety of green manure from pressing green, using formula fertilization technology. (2) deal with diseased trees. Scrape the soil to dry the roots in spring and autumn, scrape the disease department or cut off the disease roots. During the root drying period, avoid pouring water into the tree hole or being drenched by rain, dry for 7 to 10 days, scrape off the disease spot, and then irrigate the root with Bordeaux solution or 5 Bordeaux stone sulfur mixture or 45% crystal stone sulfur mixture 30 times the solution. 50% carbendazim 1000 times solution or 50% Likujing wettable powder solution can also be applied to the wound, and the control effect is also good.