Scientific control of anthracnose of amaranth

Amaranth, formerly known as amaranth, alias: Yanlaihong, old and young, tricolor amaranth, amaranth, amaranth are annual herbs, 80-150 cm high; stems stout, green or red, often branched, hairy or glabrous when young. Hairy or glabrous when young. The body of amaranth is soft and smooth, with a strong flavor, sweet and fragrant in the entrance, and has the effect of moistening the intestines and stomach and clearing heat. Also known as "sunflower", "crab vegetable", "braised vegetable", "braised vegetable". Some places are also known as "Red Mushroom Tiger", coriander, Yuntian vegetables and so on.

The efficacy of amaranth

Amaranth can replenish qi, clear heat, clear eyes, smooth fetus, benefit large and small intestines, promote the growth of teeth and bones, maintain normal myocardial activity and prevent muscle spasm. It also has the functions of promoting blood coagulation, increasing hemoglobin content, improving oxygen-carrying capacity, promoting hematopoiesis and so on. It can also lose weight and clear the body, promote detoxification and prevent constipation.

Geographical distribution

Amaranth originated in China, India and Southeast Asia. China has been eaten as a wild vegetable since ancient times. The cultivation of vegetables is mainly in China and India, and there are more in the south of China than in the north. There are some amaranth varieties with high quality and high nutrition in the south of China. Because amaranth has strong resistance, easy to grow, drought, humidity and high temperature, coupled with the rare occurrence of diseases and insect pests, amaranth is gradually recognized and developed in China and abroad.

It is cultivated all over the country, sometimes semi-wild. Originated in India, distributed in southern Asia, Central Asia, Japan and other places.

Scientific control of anthracnose of amaranth

Symptoms of anthracnose in amaranth

Anthracnose of amaranth is mainly harmful to leaves and stems. Leaves infected with primary dark green water-immersed spots, and then expanded into grayish brown, 2mm in diameter, disease spots round, margin brown, slightly raised, the number of disease spots is less than 10, up to 20: 30, serious disease spot fusion, resulting in early withering of leaves, disease spots on the birth of small black spots. When the humidity is high, the disease part overflows the slime, that is, the conidia disk and conidia of the pathogen. The stem is infected, the disease spot is brown, long oval slightly sunken.

The pathogen of anthracnose of amaranth

ColletotrichumerumpensSacc.var.amaranthiTeng. It is called Cercospora ulcera, which belongs to semi-known fungi. Conidium disk black, tufted, 60 × 300 microns in diameter; dark brown bristles around, with light top color, base slightly wider, with 1 × 3 diaphragms, size 50 ~ 200 × 4 ~ 6 microns; conidium cylindrical, short and unbranched, size 14 × 20 × 3 microns; conidia ovoid or elliptic, unicellular, colorless, size 18 ~ 26 × 3 ~ 4.5 microns.

Transmission routes and pathogenic conditions of anthracnose in amaranth

The pathogen overwintered mainly in mycelium or conidia on diseased remains and seeds. Conidia were produced in the next spring under suitable conditions, which were spread and spread by Rain Water spatter or scouring. The temperature was 2832 ℃, and heavy rain was conducive to the occurrence and epidemic of the disease. The disease was seriously affected by dense planting, partial application of available nitrogen fertilizer, poor ventilation and light transmission.

Scientific prevention and control of anthracnose of amaranth

The main results are as follows: 1) proper close planting, clear ditch and drainage, reasonable fertilization to improve plant disease resistance.

2) combined with spraying phytotin or spraying Shibao, etc., mixed with 500 times of 70% carbendazim wettable powder to control the disease with both medicine and fertilizer. In addition, you can also choose to spray 25% carbendazim wettable powder 500x liquid, 80% anthrax Fumei wettable powder 800x liquid, 2% agricultural antibiotic 120x or 1% Bo~10 water solution 200x, 70% thiophanate wettable powder 1000 times liquid plus 75% chlorothalonil wettable powder 1000 times liquid mixed spray, once every 7 to 10 days, continuous prevention and treatment for 2 times, and stop using the drug 7 days before harvest.