What are the common pest and disease control methods for yam
Yam, also called Chinese yam, is a common medicinal and edible Chinese herbal medicine in our daily lives. It helps with digestion, reduces sweating, and stops diarrhea, and when combined with reishi mushroom, it is an excellent medicinal material for preventing and treating diabetes. With the development of its medicinal and health functions, its planting area has increased year by year, but along with this come pests and diseases, which cause huge losses to yam yield and quality. So what pests and diseases affect yam and how should they be controlled? Let's take a look at the common pest and disease control methods for yam on Qinnong Web.
1. Anthracnose
Anthracnose mainly damages the leaves and stems of yam. In the early stage of the disease, small yellow-white spots appear on the leaves, gradually spreading into irregular lesions. The junction between the lesion and the leaf turns brown, and black spots appear in the center. In the late stage of the disease, the lesions perforate and the vines wither. It is caused by spores overwintering safely on diseased plant residues and spreading the following year. It is most severe during high summer temperatures, often causing plants to wither and, in severe cases, die.
Control methods: Avoid continuous cropping, and practice a 2-3 year rotation with other crops. Remove diseased plant residues promptly before overwintering. Disinfect the soil before planting. Apply more phosphorus and potassium fertilizer during planting to enhance the plants' disease resistance. When the disease occurs, spray with thiophanate-methyl at 1000 times dilution for control.
2. Brown spot disease
Brown spot disease, also called leaf blight, also mainly damages the leaves of yam. When the disease occurs, yellow-white lesions appear on the lower half of the leaves, and later the lesions spread and turn brown, with small black granules in the center. When these granules rupture, they cause the leaves to perforate. When the disease is severe, the plant's leaves wither and die. This disease is likewise caused by spore pathogens overwintering safely on diseased plants and spreading with wind and rain the following year. The incidence is extremely high, especially in humid and rainy seasons.
Control methods: Likewise practice crop rotation, do a good job of field cleaning, and eliminate overwintering pathogens. After discovering the disease, promptly prune off diseased leaves, then spray zineb fungicide, and then use chlorothalonil wettable powder for large-scale spraying control.
3. Root rot
Root rot mainly damages the rhizome part of yam. When it occurs in the root system, it is not easy to notice. In the early stage of the disease, small brown spots appear at the base of the vine stem. As time goes on, the lesions gradually expand and turn dark brown, and the center of the lesion becomes sunken. In severe cases, the lesions have brown mold-like filaments, the rhizome shrinks and rots, ultimately causing the plant to die.
Control methods: This disease is mainly spread through soil and contaminated fertilizer, and is highly prone to occurring in high-temperature and high-humidity environments. Practice crop rotation, collect and clean up diseased residues, disinfect both seeds and soil once before planting, and when the disease occurs, drench the roots with 75% chlorothalonil wettable powder at 600 times dilution.
4. White grubs and red spider mites
White grubs mainly damage the root system of yam, often gnawing on the root tubers, causing slow growth and affecting quality; red spider mites mainly damage the leaves, often gathering on the undersides of yam leaves and sucking the leaf sap, causing the leaves to lose water, turn yellow, and fall off, resulting in plant stunting and premature aging.
Control methods: White grubs can be killed by drenching with trichlorfon at 1000 times dilution, while red spider mites can be killed by spraying with propargite at 1200 times dilution.
The above are the common pest and disease control methods for yam brought to you by Qinnong Web. Due to factors such as region and climate, yam's characteristics differ, but pest and disease control should never be taken lightly. Doing a good job in pest and disease control is the prerequisite for achieving high and excellent yam yields.