Diseases of Schisandra chinensis

The common diseases in Schisandra chinensis cultivation are root rot, leaf blight, powdery mildew and so on. When using pesticides in disease control, the varieties of pesticides registered by the Drug Inspection Institute of the Ministry of Agriculture and allowed by the state must be selected to prevent the adverse effects of pesticides on the growth of Schisandra chinensis and the residual harm of highly toxic pesticides.

1. Root rot

Symptoms: the disease usually occurs from May to August. At the beginning of the disease, the epidermis at the junction of the root and the ground blackened, further cortical decay, shedding, forming a ring, the leaves wilted, and the whole plant died a few days later.

Cause: the cause is complicated. The ground changes violently in early spring and late autumn, the temperature difference is large, the tissue in the rhizome is tender, the disease resistance is low, the cortex is frozen and infected, or the rhizome is mechanically damaged. In waterlogged and waterlogged land, the disease is more serious in clayey soil, the disease is serious in plants with weak development and poor maturity of branches and vines.

Prevention and control methods:

⑴ selected loam and sandy loam to cultivate Schisandra chinensis.

⑵ strengthened field management, balanced fertilization, enhanced tree potential, and paid attention to drainage in rainy season. Before freezing in autumn, the roots should be cultivated or covered with straw to prevent the rhizome from freezing injury and the phenomenon of freezing and pulling in early spring.

The roots and plants were less damaged in ⑶ production.

At the initial stage of ⑷, 50% carbendazim WP500 solution or 77% Donin WP500 solution was used to irrigate the root, and the drugs were used continuously for 2-3 times at an interval of 7-10 days at the initial stage of the disease.

2. Leaf blight

Symptoms: every year from late May to early July, the disease first dried up from the tip or edge of the leaves, and then gradually expanded to the whole leaf surface, the leaves dried up and fell off, followed by fruit shrinkage, resulting in early fruit drop.

The cause of the disease: the air is humid and Rain Water is too large, which is more serious when the orchard is lack of fertilizer or partial application of nitrogen fertilizer, low-lying terrain and closed shelf surface. Thoroughly clean up diseased branches and leaves after falling leaves or before sprouting, burn them or bury them deeply, and reduce the density of pathogens overwintering. Before sprouting, the whole garden was sprayed with 5-Baomedo stone-sulfur mixture once. In the management, pay attention to the reasonable distribution of branches and vines, avoid the closeness of the shelf, and enhance ventilation and light transmission.

Third, powdery mildew

Symptoms: generally start with the infection of the young leaves, the back of the leaves appear needle-like spots, gradually covered with white powder, seriously extended to the whole leaf. The diseased leaves change from green to yellow, curl upward, wither and fall off. At first, the disease of young leaves gradually spread to the whole ear near the ear axis, the diseased fruit wilted and fell off, and black-brown spots appeared on fruit stalks and new shoots.

The pathogenic condition: the spores could germinate at 4-7 ℃, and the optimum temperature for germination was 25-28 ℃. It is beneficial to the disease under the condition of high temperature and drought, generally, the initial stage of the disease is from late May to early June, and it reaches the peak period in late June. The environmental conditions of excessive density of branches, excessive length of branches, excessive application of nitrogen fertilizer and poor ventilation are conducive to the occurrence of the disease.

Prevention and treatment methods: at the initial stage of the disease, 25% Fenning WP2000 solution, 45% Daconine WP800-1000 times solution, 47% plus Renong WP800 solution, 70% methyl topiramate WP1000 solution, etc., were sprayed once every 7-10 days for a total of 2-3 times.