Symptoms of the disease include damage to stolons, leaves, and in severe cases, flowers and fruits. The pathogen thrives at temperatures around 30°C, making it a typical high-temperature disease. The symptoms can be categorized into localized lesions and whole-plant wilting. When stolons and petioles are affected, near-black oval lesions appear, which are sunken and ulcer-like. Under high humidity, a pinkish or reddish bacterial ooze (brucella) may develop on the lesions. In the early stages, infected plants show only 1–2 young leaves that droop during the day but recover in the evening. However, these plants eventually die within a few days. Healthy new leaves remain green and undistorted. As the plant dies, the stem gradually turns brown from the outside inward, while the vascular bundle remains unaffected.
The disease is caused by a species of the genus *Rhizoctonia*, specifically *Rhizoctonia solani* in the strawberry industry. The pathogen overwinters in the soil and on infected plant debris. Spores are typically produced during the hot months of July to September, spreading through wind and rain. Continuous planting without crop rotation increases the risk of infection. Older leaves, leftover plant material, excessive plant density, and poor ventilation all contribute to disease development.
To manage the disease, several strategies can be employed. First, select resistant varieties such as Xinxing Star, Daxel Lake, and Baojiao Zaoxian, while avoiding susceptible ones like Lihong and Fangyu. Second, implement crop rotation between nurseries and artificial gardens, and ensure proper management of plants and stolons during the growing phase. Remove infected leaves, stems, and dead foliage promptly. Third, apply 2% Wuyimycin at a concentration of 5 ml per liter in the early stages of infection, spraying every 7–10 days for up to 2–3 applications, which has proven effective. Additionally, chemical control measures such as spraying 75% chlorothalonil diluted 600 times, 2% agricultural anti-120 water agent at 200 times, or 50% captan at 500–800 times dilution can help prevent and treat the disease. Another option is 80% anthrax Fumei diluted 500–600 times. These practices, when combined, significantly reduce the impact of the disease and promote healthier plant growth.
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