Peach gum disease and its control

1. Distribution: peach gum disease, also known as resin disease, occurs widely in various peach regions in China, especially in the south. The etiology is complex and difficult to prevent and treat thoroughly. Gum flow caused by tree weakness, affecting the quality of fruit, and even dead branches dead trees.

2. Symptoms: This disease occurs mostly in peach branches, especially in trunk and main branches. At the beginning, the disease expanded slightly, gradually overflowing translucent colloid, which was aggravated after rain. After that, the colloid gradually became frozen gel, yellow brown after losing water, and black brown when dried. Severe bark cracking, cortex necrosis, weak growth, yellow leaves, fruit taste bitter, and even branches die.

3. Pathogenesis rule: The reason of gum flow of peach tree is not very clear, and all factors that hinder the normal growth and development of peach tree may cause gum flow. According to research at home and abroad, the following factors can cause peach trees to flow gum:

(1)Due to parasitic fungi, bacteria harm, such as dry rot, rot, anthracnose, scab, ulcer disease, perforation disease, etc. can cause glue flow.

(2)Root diseases such as root cancer disease, root knot nematode disease, silver leaf disease and virus disease make tree growth weak, reduce resistance, and are also prone to gum flow.

(3)Branches and fruits are eaten by pests such as red-necked longicorn beetle, Jiding insect, woad leaf cicada, grasshopper, etc., causing gum flow from trunk, main branch and twigs, peach moth, stink bug and snail.

(4)Mechanical damage, sawing, hail damage, frost damage, sunburn, and heavy pruning can also cause gumming.

(5)Poor environmental conditions, such as poor drainage, improper irrigation, soil viscosity, soil salinization or acidification, soil magnesium deficiency, air sulfur damage, ammonia damage, etc., make peach produce physiological obstacles, but also can cause gum flow.

(6)The compatibility between rootstock and variety is poor, such as peach grafted with cherry stock and apricot stock is easy to produce gel flow.

When the pathogen is harmful, the spores spread by wind and rain, invading from wounds and lateral buds. After gum shedding due to non-infectious diseases, trees are easy to re-infect infectious diseases, especially after rain, trees quickly weaken.

4. Control methods:

(1)Strengthen soil, fertilizer and water management, improve soil physical and chemical properties, improve soil fertility and enhance tree resistance.

(2)Timely control of peach orchard diseases and insect pests.

(3)After cutting and removing the spots, apply 843 rehabilitation agent.

(4)After defoliation, trunk, big branch besmears white, prevent sunburn, freeze injury, hold antiseptic to treat insect concurrently. Whitening agent preparation method: quicklime 12 kg, salt 2~1.5 kg, soybean juice 0.5 kg, water 36 kg. First put high-quality quicklime water open, then add soybean juice and salt, stir into paste can be.

(5)At the early stage of bud expansion, spraying 5-degree sulfur mixture plus 80% sodium pentachlorophenol 200~300 times solution to eradicate overwintering bacteria.