How to treat jujube tree diseases? A practical guide to control methods

The jujube tree is a traditional cultivated plant. In rural areas, a few jujube trees can always be seen in front of and behind many houses, and their fruit is both delicious and nutritious, winning the affection of many people. As early as in the "Book of Songs·Bin Feng·Seventh Month" there is a record of“In the eighth month we beat the jujubes, in the tenth month we harvest the rice”. So how do you treat jujube trees when disease occurs?

I. Diseases of jujube trees and their treatment

The main diseases of jujube trees include jujube rust, jujube witches' broom, fruit shrinkage disease, anthracnose, and ring rot, among others. Different diseases are treated differently. When disease occurs in jujube trees, the type of disease must be determined according to the specific symptoms so that targeted treatment can be carried out.

Jujube rust mainly damages the leaves, and sometimes also infects the fruit. In the early stage of the disease, pale green small spots are scattered on the underside of the leaves, mostly on both sides of the midrib and at the leaf tip and base, gradually forming dark yellowish-brown protrusions, which are the urediniospore piles of the rust fungus. The main control measures are to strengthen cultivation management, and not to plant tall-stalk crops or crops that are frequently irrigated, such as watermelon and vegetables, between the rows. In winter and spring, sweep up fallen leaves and burn them in a concentrated manner to eliminate the source of infection. A 0.5% urea solution or a 0.3% potassium dihydrogen phosphate solution can also be sprayed 2 to 3 times.

Jujube witches' broom is one of the serious diseases of jujube trees in China. Once the disease occurs, very little fruit is produced the following year, and after 3—4 years the entire tree can die. The main manifestations are flowers turning into leaves, degeneration of the floral organs, abnormal sprouting of buds, and lesions appearing on the leaves, fruit, and roots. The main control measure is to spray each 667 sq m of jujube orchard with a 0.2% ferric chloride solution 2 to 3 times, once every 5 to 7 days, using 75 kg to 100 kg of the solution each time, and to saw off the diseased branches and roots.

Fruit shrinkage disease refers to the physiological phenomenon in which the surface of the ripe fruit is uneven and bumpy; some fruits have lost the shape and characteristics that the variety should have, and when the fruit is cut open, the flesh in the sunken areas appears brown and sponge-like; some fruits develop cracks on the uneven surface, and some fruits become deformed fruit. Generally, bacterial fruit shrinkage disease can be controlled by spraying with agricultural streptomycin at 70 to 140 units/ml + organosilicon at 3000 times dilution. Fungal fruit shrinkage disease can be controlled by spraying with 75% chlorothalonil wettable powder at 600 times + organosilicon at 3000 times dilution.

Anthracnose is caused by fungi. Spots appear on the leaves or branches, and the lesions often bear small black dots arranged in rings and breaking through the epidermis of the diseased part. Leaves with severe infection often have multiple lesions, causing the leaves and stems to wither. The common treatment method is to spray once every 7 to 10 days with 80% anthracnose thiram wettable powder at 800 times, 50% thiram wettable powder at 600 times, or 75% chlorothalonil wettable powder at 800 times, for 2 to 3 consecutive sprays.

In the early stage of ring rot, purplish-red to purplish-brown frostbite-like spots appear on the leaves, which become irregular in shape after expanding. When some lesions reach the leaf veins, they wither in a V shape. The general control method is to spray 5 degrees Baume lime sulfur mixture before the jujube tree sprouts. From the end of June to the beginning of July, spray 50% thiophanate-methyl wettable powder at 800 to 1000 times, or 50% carbendazim wettable powder at 600 to 800 times. After about 15 days, alternate with Bordeaux mixture, and after the rainy season in August, add 40% Dacotech M-45 aqueous solution at 600 to 800 times.

The above are some of the diseases of jujube trees and their treatment methods. When growing jujube trees, you must observe carefully, and after discovering disease, take targeted measures for treatment.