Prevention and Control of White Silk Disease of Lily

Symptoms: the whole plant withered, the stem base wrapped around white fungal cords or rapeseed tea brown sclerotia, the affected area became brown and rotten. A large number of white fungal cords and tea-brown sclerotia can be seen on the soil surface.

Pathogen: SclerotiumrolfsiiSacc. It is called Sclerotinia sclerotiorum, which belongs to the subphylum fungus. The hyphae were white silk-like, fan-like or radial expansion, and then gathered into fungal cords or entangled sclerotia. Sclerotia is like rapeseed, the initial white to yellow-white, and then become tea-brown, round, smooth surface.

Route of infection:

① bacteria overwintered in the soil with sclerotia or fungal cords. When the conditions were suitable in the next year, sclerotia or mycelium produced hyphae for primary infection.

The filamentous hyphae produced by ② disease plants extended to contact adjacent plants or sclerotia were re-infected by water transmission, resulting in the spread of the disease, continuous cropping or soil clay weight and low-lying or high-temperature and humid years or seasons.

Prevention and control methods:

1. Avoid continuous cropping in seriously ill areas, preferably in rotation with cereal crops. The control effect of flood-drought rotation is obvious.

2. Timely inspection, timely removal and burning of diseased plants, irrigation of 5% Jinggangmycin water solution 1000 times, or 50% Tianan water agent 500 times 600 times, or 20% methyl rifampicin EC 1000 times, or 1000 times of 90% dimethophos wettable powder, 0.4 × 0.5 liter per plant (hole). 15% powder is rather wettable powder or mixed with 40% pentachloronitrobenzene and fine sand into 1 ∶ 200x medicinal soil, 100g 150g per hole, once every 10 to 15 days.

3, combined with ploughing, mixed with each mu. 500kg lime powder slightly alkalized the soil and inhibited the breeding of Alternaria alternata.