What are the pest and disease control methods for Chuanxiong (Medicinal cyathula, Cyathula officinalis)?

The main disease during the growing period of Medicinal cyathula (Cyathula officinalis) is white rust. The symptoms of this disease are that all aboveground parts of the plant can be affected, manifesting as damage to the leaves, with pale yellow-green patches appearing on the leaf surface and corresponding blister-like protrusions growing on the underside, 1-2 mm in diameter. After the epidermis ruptures, a white, glossy, sticky-slimy powdery substance is released. When many blister spots occur, the diseased leaves turn yellow and brown. When it occurs on parts such as leaf petioles and young buds, pale yellow spots are produced, which later become white blister spots, and the diseased stems are often swollen and twisted.

The pattern of white rust development is that the pathogen mainly overwinters as oospores in the diseased tissues or attached to seeds, and later germinates to produce sporangia and zoospores. The zoospores germinate and grow germ tubes, which invade the host through stomata and cause disease. The sporangia produced on the host's diseased spots spread through wind and rain and cause secondary infection. In addition, the mycelium can also overwinter on seed plants and produce sporangia that spread and cause damage.

White rust is usually aggravated by low temperature and high humidity. The optimum temperature for the germination of sporangia and oospores is 10°C, the minimum is 1°C, and the maximum is 20°C. Under high temperature (above 25°C) or drought, sporangia and oospores cannot germinate. If the air

temperature has a large day-night difference and dew condenses, it is favorable for the germination and invasion of sporangia. In spring and autumn with continuous rainy weather and in fields with poor drainage, white rust is prone to occur.

In terms of control measures, prevention is mainly carried out by improving cultivation techniques. First, pay attention to crop rotation, deep plowing, and removal of diseased plant residues. Second, in the cold and rainy spring season, dig ditches to drain water and reduce field humidity. Third, starting from early March, spray 40% fosetyl-aluminum 200-300 times dilution, or use 50% thiophanate-methyl 800-1000 times dilution, or use metalaxyl, Bordeaux mixture, etc. for chemical control.

In addition, when planting Medicinal cyathula (Cyathula officinalis), attention should also be paid to the occurrence of black head disease and nematode disease. Black head disease mostly occurs in spring and summer, mainly because the reed head is covered too thinly and suffers cold damage in winter, causing blackening and rotting. The control method is to pay attention to drainage and waterlogging prevention, and to earth up in winter. Nematode disease mostly occurs in low-altitude areas, forming uneven fleshy galls on the roots. For control, pay attention to soil selection; 35-45 kg of DD mixture per mu can be used to treat the soil.

The main insect pests throughout the entire growth period of Medicinal cyathula (Cyathula officinalis) are caterpillars and red spider mites. They generally occur from May to June each year, and the damage is severe when the weather is dry. For control, 500 g of Dongguo emulsion can be added to 1000 kg of water and sprayed. In addition, pay attention to weeding, and avoid intercropping or adjacent cropping with beans, cotton, and similar crops.

The large flea beetle that harms Medicinal cyathula (Cyathula officinalis) generally occurs from May to June. The symptom is that the insects bite the leaves into small holes. For control, 800 times dilution of phosmet or 1000 times dilution of trichlorfon can be sprayed to kill them.

When the temperature has a large day-night difference and dew condenses, it is favorable for the germination and invasion of sporangia. In spring and autumn with continuous rainy weather and in fields with poor drainage, white rust is prone to occur.

In terms of control measures, prevention is mainly carried out by improving cultivation techniques. First, pay attention to crop rotation, deep plowing, and removal of diseased plant residues. Second, in the cold and rainy spring season, dig ditches to drain water and reduce field humidity. Third, starting from early March, spray 40% fosetyl-aluminum 200-300 times dilution, or use 50% thiophanate-methyl 800-1000 times dilution, or use metalaxyl, Bordeaux mixture, etc. for chemical control.

In addition, when planting Medicinal cyathula (Cyathula officinalis), attention should also be paid to the occurrence of black head disease and nematode disease. Black head disease mostly occurs in spring and summer, mainly because the reed head is covered too thinly and suffers cold damage in winter, causing blackening and rotting. The control method is to pay attention to drainage and waterlogging prevention, and to earth up in winter. Nematode disease mostly occurs in low-altitude areas, forming uneven fleshy galls on the roots. For control, pay attention to soil selection; 35-45 kg of DD mixture per mu can be used to treat the soil.

The main insect pests throughout the entire growth period of Medicinal cyathula (Cyathula officinalis) are caterpillars and red spider mites. They generally occur from May to June each year, and the damage is severe when the weather is dry. For control, 500 g of Dongguo emulsion can be added to 1000 kg of water and sprayed. In addition, pay attention to weeding, and avoid intercropping or adjacent cropping with beans, cotton, and similar crops.

The large flea beetle that harms Medicinal cyathula (Cyathula officinalis) generally occurs from May to June. The symptom is that the insects bite the leaves into small holes. For control, 800 times dilution of phosmet or 1000 times dilution of trichlorfon can be sprayed to kill them.