MySheen

Leaf rot of medicinal plant Panax notoginseng

Published: 2024-11-24 Author: mysheen
Last Updated: 2024/11/24, Symptoms can affect all aerial organs except the roots. The most typical symptom is to cause black fusiform lesions on the top of petioles. When the temperature is high, they quickly circle around the petioles and quickly expand to the base of the leaflets, forming pale black water-soaked lesions on the leaves with irregular edges. The diseased part of the petiole softens quickly, causing the upper leaflet to droop (commonly known as "twisted footwall"). In the disease often visible yellow with pink mold, that is, the fruiting body of the pathogen. When it damages the middle part of the leaf, it forms black irregular spots with irregular edges.

Symptoms the disease can damage all aboveground organs except the root. The most typical symptom is to cause a black fusiform spot at the top of the petiole, which quickly circles the petiole when the temperature is high and quickly expands to the base of the leaflet, forming a light black water-immersed spot on the leaf with irregular edges. The diseased part of the petiole soon softens, causing the upper lobule to droop (commonly known as "twisting the lower plate"). Yellowish pink mildew, the fruiting body of the pathogen, is often seen in the disease department. In order to harm the middle of the leaf, black irregular disease spot is formed, the edge is irregular, the size is generally 5-13mm, the disease part is rotten, the edge is neat when dry, the middle is easy to fall and form holes; the flower cluster is vulnerable, the symptom is the same as the petiole damage; when the stem is damaged, it forms a black-brown fusiform disease spot, but expands slowly.

Verticillium μ mcinnabari μ m (Cda.) ReinkeetBerth. It is called Cladosporium verticillium, which belongs to the subphylum fungus. On PDA medium, the mycelium was initially white and then orange-yellow; the hyphae were slender, nearly colorless, 1.6-2.2 μ m in diameter, separated and could be clustered into bundles; the conidiophores in the mycelia could be clustered together, and the conidiophores were obviously different from the hyphae, 40-82 × 1.4-1.7 (μ m), branching at an acute angle of 30-40 °, branching for 3 times, 6 pedicels on the branches, whorled, 9-13 × 1.4-1.7 (μ m). Conidia ovoid or long oval, sometimes slightly curved, unicellular, colorless, with a large number of conidia, the size of which is 3Mel 7 × 2Mel 3 (μ m).

The route of transmission, incidence conditions, prevention and treatment methods see Datura verticillium wilt.

 
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