Pest and Disease Control Methods and Technical Key Points for Burdock Fruit

Burdock FruitDiseases: Burdock gray leaf spot mainly damages the leaves. The lesions are nearly round, 1-5mm, brown to dark brown, and in the later stage the central part turns grayish white. When humid, light black mold-like substances grow on both sides, which are the fruiting bodies of the pathogen. Control methods: Clean the field in autumn and thoroughly remove diseased plant residues. Maintain reasonable planting density, cultivate and weed in time, and control nitrogen fertilizer application. At the early stage of the disease, spray Bordeaux mixture at 1:1:150 or 75% chlorothalonil wettable powder at 500 times dilution.

Burdock ring spot: The lesions on the leaves are nearly round, 2-12mm, dark brown, later the center turns grayish white, the edges are irregular, with slight concentric rings, and small black dots grow on them, which are the pycnidia of the pathogen. The control methods are the same as for gray leaf spot. Burdock powdery mildew: White powdery spots grow on both sides of the leaves, and later black dots grow on the powdery spots, which are the cleistothecia of the pathogen. Control methods: Thoroughly remove diseased plant residues to reduce overwintering inoculum sources. At the early stage of the disease, spray 50% thiophanate-methyl wettable powder at 1000 times dilution.

The main pests are safflower finger tube aphid and chrysanthemum small long tube aphid. They damage stems, leaves and fruits, and can cause total crop failure in severe cases. Spray 40% omethoate emulsifiable concentrate at 1000 times dilution, or 10% fenvalerate emulsifiable concentrate at 3000 times dilution, or 50% menazon emulsifiable concentrate at 1000-1500 times dilution for control. Cotton bollworm: Larvae chew the leaves, causing notches and holes. Spray 90% trichlorfon crystal at 800-1000 times dilution for control. Cotton bollworm larvae damage the leaves, causing notches on the leaves; in severe cases, the flowers and young fruits are all damaged, causing substantial yield reduction. Control methods: Adopt winter plowing and winter irrigation to kill overwintering pupae and reduce the next year's pest sources. Use 20w black light lamps to trap and kill adults. Before the larvae reach the 3rd instar, use 90% trichlorfon crystal at 1000 times dilution, or 25% phosmet at 300-400 times dilution for control. Cutworm: Larvae bite the leaves or heart leaves. Trichlorfon poison bait can be used to trap and kill them, or manual killing can be done in the morning. Ants: They eat the main root, and in severe cases the plants die in patches. Pour 80% dichlorvos emulsifiable concentrate at 2000 times dilution around the roots; animal bones can also be used to trap and kill them. Harvesting and processing: Harvest around “Start of Autumn” in the 2nd year after sowing. Because the seed maturity period is very inconsistent, harvesting should be done in stages. When the involucre of the fruit cluster turns withered yellow, it can be harvested. Cut off the fruit branches, dry them in the sun, and finally cut down the whole plant, dry it in the sun, remove all impurities, and store it. If not harvested for a long time, the fruits will become overripe and are easily blown off by the wind. Because there are many hard hooked spines on the involucre, picking should be done in the morning and on cloudy days when the spines are soft, so as not to hurt the hands. If picking on sunny days, gloves should be worn.