Symptoms and control of root rot of Sophora flavescens

Sophora flavescens (scientific name: Sophora flavescens) is a plant of the genus Sophora. It is distributed in Russia, Japan, India, Korea and the northern and southern provinces of the mainland of China. It grows at an altitude of 1,500 meters. It grows mostly on hillsides, sandy lands, grass slopes, shrubs and fields. It has not been introduced and cultivated artificially. Indications: clearing away heat, drying dampness, killing insects, diuresis. For hot diarrhea, hematochezia, jaundice, urine retention, red leucorrhea, pudendal itching, eczema, wet sores, skin itching, scabies leprosy; external treatment trichomonas vaginitis. Morphological characteristics of Sophora flavescens deciduous semi-shrub, high 1.5~3m. Root terete, rind yellow-white. Stems erect, much branched, longitudinally grooved; young branches sparsely hairy, glabrous. Odd-pinnate compound leaves, 20 - 25cm long, alternate; leaflets 15 - 29, leaf blade lanceolate to linear-lanceolate, 3 - 4 cm long, 1.2 - 2 cm wide, apex acuminate, base rounded, shortly stalked, entire, abaxially densely adnate; stipules linear. Racemes terminal, 15 - 20cm long, shortly hairy, bracts linear; calyx campanulate, flattened, 6 - 7mm long, 5-lobed; corolla butterfly, yellowish white; flag petals spatulate, wings auriculate, as long as keel; stamens 10, filaments separate; ovary stipe fine hairy, stigma round. Pods linear, apex long beaked, indehiscent at maturity, 5 - 8cm long. Seeds slightly constricted, inconspicuously beaded, sparsely pubescent. Seeds 3 - 7, subglobose, black. The flowering period is from June to July, and the fruiting period is from July to September. The root rot of Sophora flavescens has seriously affected the planting benefit of Sophora flavescens, so what are the symptoms of root rot of Sophora flavescens and how to control it? What is root rot? Root rot is caused by root rot, which gradually weakens the function of absorbing water and nutrients, and finally the whole plant dies. It is mainly characterized by yellowing and withering of whole leaves. Generally, the disease occurs from late March to early April, and enters the peak period in May. Sophora root rot harm symptoms: Sophora root rot occurs in high temperature rainy season, harm plant roots. Only a few roots or a part of underground rhizomes develop disease at the initial stage, and gradually expand to the whole root system. After the root is damaged, wet rot occurs, the outer skin is black, some branches and leaves die in the early stage of the disease on the ground, and the whole plant dies seriously. There are different degrees of harm in Sophora flavescens production areas, resulting in certain losses. Control method of root rot of Sophora flavescens

1. Implement rotation: due to soil bacteria, Sophora flavescens continuous cropping disease early, serious disease, rapid spread. It is best to rotate with grass crops for 3 to 5 years to reduce the pathogen base and reduce the incidence.

2. Healthy seed retention: select disease-resistant varieties; select healthy disease-free seed roots; do not leave seeds in diseased fields to reduce diseases.

3. Strengthen field management: apply fertilizer reasonably, apply more organic fertilizer, increase phosphorus fertilizer and potassium fertilizer; remove accumulated water in time in rainy season, pay attention to loose soil, and improve plant disease resistance.

4. Chemical control: 1 kg/mu of 70% Dikosong WP or 50% Carbendazim WP mixed with 3 kg of fine soil, sprinkled into the hole when planting, has certain control effect; Disinfect the cuttings and reeds, soak the cuttings and reeds with 800 times solution of 50% Tuijunte WP or 1000 times solution of 70% Thiophanate-methyl WP for 3 - 5 minutes, dry and seed; During the growth period, fungicides are used to irrigate around the roots of the diseased plants at the early stage of the disease, which can control the spread of the disease. Commonly used pesticides include 50% Miaoling WP or 50% Dikesong WP 500~800 times solution, or 96% copper sulfate 1000 times solution, or 3% agricultural antibiotic 120 solution 100~150 times solution, once every 10~15 days, for 3~4 times continuously.