How to prevent and control white rust in amaranth? A detailed explanation of the latest methods

Amaranth not only has excellent edible value, but also extremely high medicinal value, so amaranth is also deeply loved by many people, but during the planting process it is inevitably harmed by various pests and diseases. White rust is one of the common ones. Below, the editor brings you the prevention and control methods for amaranth white rust. Let's take a look together.

1. Disease occurrence pattern

White rust is a common disease of amaranth. When the disease is epidemic, the diseased plant rate can reach 20%-40%, and sometimes as high as over 80%. Diseased leaves are covered with blister-like spots, affecting the appearance and quality of the vegetable. Because the pathogen overwinters or oversummers as spores remaining in diseased residues, soil and fertilizer, and can survive for more than two years, plots with severe disease in the previous year may still continue to develop the disease in the second year even after prevention and control. This disease can occur throughout the entire growth period of amaranth, and is more severe in high-temperature and high-humidity environments. In addition, low-lying terrain, improper irrigation, overly dense planting, poor permeability, and excessive application of nitrogen fertilizer can also cause more severe disease. Overly dense sowing leads to more severe disease, while drilling is conducive to ventilation and moisture dissipation, resulting in lighter disease.

2. Seed and soil treatment

Before the shelf life of amaranth seeds, it is best to sun them in the sun for 1-2 hours to kill surface miscellaneous bacteria and improve the germination rate, then mix the seeds with chemicals to reduce the chance of disease damage. Similarly, the seedbed can also be disinfected with chemicals to minimize the number of pathogens, inhibit their growth and reproduction, and reduce the chance of disease.

3. Agricultural control

Choose varieties with strong disease resistance. For example, purple amaranth has a lower degree of disease than green amaranth. In areas or plots with severe disease, rotation with non-host crops for more than 1 year can be carried out. Choose plots with good drainage for planting, make drainage ditches well to avoid flood irrigation, drain water promptly after rain to reduce waterlogging, lower field humidity, and plant appropriately densely. If plants are too dense, they should be thinned promptly to avoid field closure, which affects permeability and improves disease resistance. Fertilize reasonably, increase the application of phosphorus and potassium fertilizer, avoid excessive application of nitrogen fertilizer, so as to enhance plant stress resistance. If diseased plants are found, remove them promptly and take them out of the field to burn, effectively controlling and inhibiting the spread of the disease.

4. Chemical control

In the early stage of the disease, sprays such as mancozeb, copper hydroxide, and propamocarb hydrochloride aqueous solution can be used for control, once every 7-10 days, for 2-3 consecutive treatments. At the same time, spray 30-50 ml per mu of yield-increasing bacteria or 6000-9000 times dilution of Zhibaosu, used alternately for better effect, but note that medication should be stopped 15-20 days before harvest.

The above is an introduction to the prevention and control methods for amaranth white rust. We hope it can help you. If you want to learn more related knowledge, please stay tuned to us.