A Detailed Guide to Scientific Control Methods for Amaranth Anthracnose
Amaranth, original name: amaranth, aliases: Love-lies-bleeding, Old Youth, Old Fewer, tricolor amaranth, Amaranthaceae; amaranth is an annual herb, 80-150 cm tall; the stem is stout, green or red, often branched, hairy or hairless when young. Hairy or hairless when young. The amaranth plant is soft and smooth with a rich vegetable flavor, sweet and fragrant on the palate, and has the effect of moistening the intestines and clearing heat. It is also called "fukui", "crab vegetable", "xingcai", "xingcai". In some places it is also known as "red mushroom tiger", cloud fragrant vegetable, cloud sky vegetable, etc.
The effects and functions of amaranth
Amaranth can tonify qi, clear heat, improve eyesight, promote smooth labor, and benefit the large and small intestines, and it can promote the growth of teeth and bones, and can maintain normal cardiac muscle activity, preventing muscle cramps. It also has the functions of promoting blood coagulation, increasing hemoglobin content and improving oxygen-carrying capacity, and promoting hematopoiesis. It can also reduce weight and cleanse the body, promote detoxification, and prevent constipation.
Geographical distribution
Amaranth originated in China, India, and Southeast Asia, and has been eaten as a wild vegetable in China since ancient times. As a cultivated vegetable, it is mostly grown in China and India, and more in southern China than in the north. In various parts of southern China there are some amaranth varieties with excellent quality and high nutrition. Because amaranth has strong resistance, is easy to grow, tolerates drought, tolerates moisture, and tolerates high temperatures, and because diseases and pests rarely occur, amaranth, whether in China or abroad, has gradually become known to people and has developed.
It is cultivated throughout the country, and sometimes escapes to semi-wild status. Native to India, distributed in southern Asia, central Asia, Japan, and other places.
Scientific control of amaranth anthracnose
Symptoms of amaranth anthracnose
Amaranth anthracnose mainly damages leaves and stems. When leaves are infected, small dark green water-soaked spots first appear, which later expand to grayish brown, 2-4 mm in diameter; the lesions are round, with brown edges and slightly raised. The number of lesions may be as few as 10-plus, or as many as 20-30, and severe cases merge, causing early leaf withering, with small black granular dots on the lesions. When humidity is high, the diseased part exudes a sticky substance, namely the pathogen's acervuli and conidia. When stems are infected, the lesions are brown, long-oval, and slightly sunken.
The pathogen of amaranth anthracnose
ColletotrichumerumpensSacc.var.amaranthiTeng., called ulcerative spine colletotrichum, belongs to the Deuteromycetes fungi. Acervuli are black, clustered, 60-300 micrometers in diameter; surrounded by dark brown setae, with lighter tips and slightly wider bases, having 1-3 transverse septa, size 50-200×4-6 micrometers; conidiophores are cylindrical, short and unbranched, size 14-20×3 micrometers; conidia are ovoid or elliptical, single-celled, colorless, size 18-26×3-4.5 micrometers.
Transmission routes and disease conditions of amaranth anthracnose
The pathogen mainly overwinters as mycelium or conidia on diseased residues and seeds. When conditions are suitable in the following spring, conidia are produced and spread and spread through rain splash or washing. A temperature of 28-32°C and abundant rain favor the occurrence and epidemic of this disease. Overdense planting, excessive application of quick-acting nitrogen fertilizer, and poor ventilation and light transmission lead to severe disease.
Scientific control methods for amaranth anthracnose
1) Plant at an appropriate density, clear ditches and drain waterlogging, fertilize reasonably, and improve plant disease resistance.
2) In combination with spraying plant growth regulators such as Zhilaobao or PenShiBao, mix in 70% carbendazim wettable powder 500 times solution, so as to apply both pesticide and fertilizer to control the disease. In addition, you may also choose to spray 25% tanteling wettable powder 500 times solution, 80% anthracnose fumet wettable powder 800 times solution, 2% agricultural antibiotic 120 or 1% agricultural antibiotic Wuyi mycin (Bo-10) aqueous solution 200 times solution, 70% thiophanate-methyl wettable powder 1000 times solution plus 75% chlorothalonil wettable powder 1000 times solution mixed and sprayed, once every 7-10 days, for 2-3 consecutive treatments, and stop using the drug 7 days before harvest.