Symptoms The disease occurs in all tea regions in the country and is mainly responsible for the damage to the leaves. The young leaves, the leaves, and the old leaves are infected, and most of them develop pale brown lesions from the tips of the leaves or leaves, and then spread to the half leaves or the whole leaves, forming irregular large-scale lesions. The lesions are more uniform in color and appear darker. Reddish-brown to auburn brown, with dark brown ridges on the edges, very distinct from the healthy part, and the late diseased part gives rise to slightly raised black granules, which are the conidia of the pathogenic bacteria.
The pathogen Phyllosticta theicola Petch said that it is a fungus that is a fungus of the subphylum Aspergillus. Conidiophores hemispherical or spherical, black, size 70 ~ 100μm, with orifices, conidial stems on the inner wall, the upper conidia. The conidia unit cells are colorless, round to wide circular, and size 7 to 126 to 8 (μm). When the humidity is high, the spores resemble crushed toothpaste and emerge from the conidia.
Pathogens and pathogenic conditions The pathogens overwinter in tea diseased leaf tissue with mycelia and conidia. In May of the following year, conidia began to be produced, spread by wind and rain, and water droplets. The disease was caused by infestation into leaves, and the diseased part was again contaminated and repeatedly infested. The disease is a disease of high temperature and high humidity, and spores are re-infected several times in May-June. The disease is a high-temperature, high-humidity disease, which begins in May-June, and enters the onset of disease in July-August. Tea garden water shortage, tea tree water supply, decreased resistance is easy to induce the disease. There are many twigs and twigs after the rakes and pruning, picking leaves are not net or summer drought, transpiration, root water supply is insufficient, susceptible to bacteria infection. On the production, the sunny slopes or shallow soil layers or terraced tea gardens developed poorly and heavily, causing the entire tea plantation to be reddish-brown and dry and defoliated.
Prevention and control methods (1) Promote the application of enzyme bacteria or EM active bio-organic fertilizer, improve soil physical and chemical properties and water retention and fertilizer protection, is the fundamental measure to prevent and treat the disease. (2) Summer drought should be promptly irrigated, and shade trees should be properly planted to reduce direct sunlight and prevent sunburn. (3) Spray 50% benomyl WP 1500 times or 70% carbendazim WP 900 times and 36% thiophanate-methyl suspension 600 times before summer drought. For other methods, see Tea Moiré Disease.