How to prevent and control white rust in amaranth

Amaranth, original name: amaranth, aliases: Joseph's coat, old youth, old age few, tricolor amaranth, Latin name: Amaranthus tricolor, Amaranthaceae, Amaranthus genus annual herb, stem stout, green or red, often branched, hairy or hairless when young. Amaranth has a soft and smooth texture and a rich vegetable flavor, sweet and fragrant on the palate, and has the effect of moistening the intestines and stomach and clearing heat. Also called “fú kuí”, “crab vegetable”, “xìng cài”, “xìng cài”. In some places it is also called “red mushroom tiger”, cloud fragrant vegetable, cloud sky vegetable, cold vegetable, etc.

The main value of amaranth

The stems and leaves are eaten as a vegetable; the leaves mixed with various colors are for ornamental use; the roots, fruits and the whole plant are used as medicine, with the effects of improving eyesight, promoting urination and defecation, and removing cold and heat.

The effects and functions of amaranth

Amaranth can tonify qi, clear heat, improve eyesight, smooth labor, and promote urination and bowel movement, and can promote the growth of teeth and bones, and can maintain normal myocardial activity and prevent muscle spasms. It also has functions such as 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.

Amaranth leaves are rich in calcium that is easily absorbed by the human body, can promote the growth of teeth and bones, and can maintain normal myocardial activity and prevent muscle spasms. At the same time, they contain rich iron, calcium and vitamin K, which can promote blood coagulation.

Amaranth is rich in dietary fiber, and regular consumption can reduce weight and lighten the body, promote detoxification, and prevent constipation. At the same time, regular consumption of amaranth can strengthen the physique, and the content is higher than that of solanaceous fruits, and it has the title of "longevity vegetable".

Amaranth can promote the growth and development of children, and its iron and calcium content is higher than that of spinach, making it outstanding among fresh vegetables. It is also suitable for anemia patients, women and the elderly, maintaining normal myocardial activity, and promoting blood coagulation, hematopoiesis and the blood's oxygen-carrying function.

How to prevent and control amaranth white rust?

1) Symptoms of amaranth white rust: it mainly harms the leaves. Irregular faded patches first appear on the leaf surface, and round to irregular white blister-like spore piles grow on the leaf back, with a diameter of 1-10 mm. In severe cases, the blister spots are densely distributed or joined together, the leaves are uneven, and eventually turn yellow and withered, becoming unfit to eat.

2) Conditions for the occurrence of amaranth white rust: it is a fungal disease. In cold regions, the pathogen overwinters as oospores in the soil with diseased residues. The following year, the oospores germinate to produce sporangia or directly produce germ tubes to infect and cause disease. In warm regions, the pathogen infects by sporangia, spreads and expands by airflow or rain splash, completing the annual disease cycle. The optimum temperature for sporangium germination is 10°C, and sufficient water and moisture conditions are required. Continuous rainy weather and excessive application of nitrogen fertilizer make the disease severe.

3) Prevention and control methods for amaranth white rust:

① Select and retain seeds from disease-free plants, and before sowing use 0.2%-0.3% of seed weight of 25% Ridomil wettable powder, or 64% Sandofan wettable powder for seed dressing.

② Strengthen fertilizer and water management, plant at moderate density, clear ditches and drain waterlogging to reduce humidity, and avoid excessive application of nitrogen fertilizer.

③ Chemical control: at the early stage of disease, choose to spray 58% Ridomil.mancozeb wettable powder 500 times dilution, or 50% metamfos-copper wettable powder 600-700 times dilution, or 64% Sandofan wettable powder 500 times dilution, or 60% metamfos-aluminum-copper wettable powder 500-600 times dilution; for the above agents, pay attention to alternating use, once every 7-10 days, spraying 2-3 times in succession.