Lily Fusarium wilt

Latin scientific name: Fusariumoxysporumf.sp.liliSnyderetHansen

Damage to crops: Lily

Damage symptoms: also known as stem rot, is an important disease in lily production. At the initial stage, the infected plant showed slow growth, the lower leaves yellowed and lost luster, and then the symptoms gradually spread upwards. finally, the leaves of the whole plant wilted and drooped, browned and withered. In addition, the specific type of Fusarium oxysporum lily can also infect the base of the bulb skin, and brown necrosis or rot appears on the base plate, resulting in scattered scales. The leaves of the plants growing from the diseased bulbs turn yellow or purple, the flower stems are few and small, and the bulbs split when they are not all rotten, causing the bulbs to rot and die.

Morphological characteristics of pathogens: large conidia meniscus, with 3-5 separations, size 17.5-21 × 3.5-4.9 (microns). F3 aerial mycelium fouling white, colony sparse, spreading sticky, small conidia ovoid, 0-1 separated, one tip, the other obtuse, size 6.3-12.6 × 2.8-4.9 (micron), large conidia meniscus, 2-4 separations, tip cutting, size 17.5-35 × 2.8-7 (micron). Fusoriummoniliforme began to show white fluffy round colonies on PSA medium, and the bacteria grew rapidly on the medium, and purple pigment was produced in the later stage. Sometimes orange-orange conidia can be produced. The surface of the substrate is purple, and the culture medium does not change color. The pathogen produces conidia of large and small types. Large conidia fusiform to sickle-shaped, straight or slightly curved, with 3-5 septum, 3 diaphragm size 25-55 × 3-4.5 (micron). There are a large number of small conidia, ovate to oval, serial on sporogenic cells and pseudocephalous. A few with 1 septum, 7-11.5X2-3 (micron) Fusariumsolani spore seat mattress, bright color, conidia born on the spore pile, with large and small conidia. Large conidia sickle-shaped, five-colored, multicellular, septate; small conidia ovoid, single cell colorless; later gathered by hyphae to form black flaky sclerotia.

Taxonomic attribute: half-known fungi

Characteristics of the disease: the pathogen overwintered in the soil with mycelium in the bulb or with mycelium and sclerotia in the soil, becoming the source of infection at the beginning of the next year. The disease often occurs at the same time as other underground root rot and scale rot of lilies. Diseased bulbs and contaminated soil are the main sources of infection of the disease. After flowering, the disease is easy to occur due to high temperature and frequent rainfall, and the wounds caused by continuous cropping, underground pests and root-knot nematodes are often seriously ill.

The methods of prevention and control are as follows: (1) implement crop rotation. (2) applying the compost made by Baode biological fertilizer or enzyme bacteria retting, applying less ammonia nitrogen fertilizer and increasing phosphorus and potassium fertilizer to enhance disease resistance. (3) the disease-free and injury-free bulb was selected as the propagation material. (4) before planting, soak the bulb in 40% pentachloronitrobenzene 200 times solution and 50% Fumei 200 times mixture for 15 minutes, or soak in 50% carbendazim wettable powder 2000 times solution, 30 ℃ water temperature for 30 minutes, or the bulb can be treated with 39 ℃ warm water for 2 hours, and then immersed in 50% carbendazim 2000 times solution for 30 minutes. The seeds can also be soaked in 43% formalin 120 times solution for 3.5 hours, and the control effect is obvious. (5) sprinkling 36% thiophanate methyl suspension or 50% methyl thiophanate sulfur suspension 1000 times, 50% carbendazim wettable powder 1000 times, 12.5% carbendazim concentrated solvent 300x, 50% carbendazim (chlorobromaisocyanuric acid) water soluble powder 1000 times.

Commonly used agents: carbendazim methyl sulfur synergistic carbendazim