What are the common pests and diseases of American ginseng? A detailed guide to prevention and control methods

American ginseng is a relatively precious medicinal herb, and the older the root, the more expensive it is, and the higher its medicinal value. However, the age of American ginseng on the market today is generally not very high. Due to the scarcity of wild resources, the yield from home cultivation is also not very high, while market demand is relatively large, so supply falls short of demand in the market. If you want to increase yield, you need to prevent some of the diseases that appear during the growing process, so that you can produce high-quality, high-yield American ginseng. Below is a guide from Qinnong.com on the prevention and control methods for some pests and diseases of American ginseng, and we hope it can help everyone.

1. Black spot disease

Black spot disease in American ginseng generally appears on the leaves and stems, and sometimes also on the fruit. In the early stage of the disease, scattered oval dark brown spots appear on the leaf surface or stems. If no prevention and control is carried out, the color will gradually deepen and continue to spread, eventually appearing on the fruit of American ginseng and then penetrating into the fruit, by which point such American ginseng has no value at all. The cause of this type of disease is generally relatively heavy rain without timely drainage. The most basic prevention and control method is seed treatment, which means mixing American ginseng seeds with an agent against black spot disease at planting time, so as to strengthen the resistance of American ginseng. When the disease occurs, we need to alternate spraying with Bordeaux mixture and chlorothalonil.

2. Phytophthora blight

Phytophthora blight in American ginseng generally occurs in June and July in summer. At this time the temperature is very high and rainfall is also relatively heavy, so it is very easy to trigger the disease. Phytophthora blight mainly damages the roots of American ginseng, causing the roots to rot. If it is not prevented and controlled in time, then when you dig up the American ginseng, basically not a single root will be intact. The prevention and control method is to dig trenches all around at planting time, so as to facilitate drainage. Next, the grass and wood used to cover American ginseng last year must not be used a second time. Finally, at planting time, spread quicklime into the holes. When symptoms occur, mancozeb can be used for prevention and control, and the effect is quite good.

3. Damping-off

The symptom of damping-off is that American ginseng seedlings lodge, and it slowly spreads, resulting in patches of lodging. It seriously affects the growth and yield of American ginseng. Its spreading ability and infectivity are both very strong, so we must be very careful in ordinary field management. We need to regulate the temperature and humidity in the field well. Next, as soon as one or two seedlings are found lodging, chemical treatment should be carried out. The agents used are carbendazim or antimycin. Carbendazim is mostly used for covering soil and seed dressing, while antimycin is used for spraying. At the same time, Bordeaux mixture can also be used, with a similar effect.

4. Cutworms

Cutworms are the natural enemy of root and stem plants. They especially like to bite the roots and stems of plants, which affects the growth rate of the plants, and in severe cases causes the plants to stop growing. So we generally prevent and control them by using trichlorfon, or by buying some trapping devices for cutworms to trap and kill them.

5. White grubs

White grubs are actually the pest most disliked by American ginseng and even all ginseng types. The main efficacy and valuable part of American ginseng is the root, and white grubs especially like to eat root things. If white grubs are encountered during the planting process, then in severe cases basically no American ginseng output can be seen. So in order to avoid having all your hard work go to waste, you need to make prevention preparations in advance. When necessary, trichlorfon and phoxim emulsifiable concentrate need to be used alternately to kill the insects.