What new methods are there for preventing and controlling ginger bacterial wilt?

Ginger bacterial wilt easily occurs on a large scale in hot and rainy seasons, and it is the disease most feared in ginger cultivation. Once ginger bacterial wilt occurs, if it is not treated in time, it will cause serious economic losses. So what new methods are there for preventing and controlling ginger bacterial wilt at present?

1. Symptoms of ginger bacterial wilt

Ginger bacterial wilt is caused by infection by the bacterium Ralstonia solanacearum. The pathogen infects the roots and the underground and aboveground stems. The affected underground fleshy stem initially appears water-soaked and yellowish-brown, and after losing its gloss, the internal tissue gradually softens and rots, leaving only the outer skin.

When the diseased part is squeezed, a dirty-white turbid juice can flow out, giving off a foul odor; the affected roots also turn pale yellowish-brown and eventually rot completely. The affected aboveground stems appear dark purple, and the internal tissue turns brown and rots, leaving fibers behind. The affected leaves appear wilted, the leaf color becomes pale yellow, the edges curl, and eventually the whole plant dies.

2. Prevention and control methods for ginger bacterial wilt

For ginger bacterial wilt, prevention should be the main approach, combining prevention and control.

1. Prevention of ginger bacterial wilt

(1) Seed ginger disinfection: carry this out before storing in the cellar and before taking out of the cellar for sprouting. The method is to place the seed ginger side by side on the ground, air-dry the surface moisture, spray the entire surface of the ginger with a 300-fold dilution of Jiangwenjing, cover it with sacks or similar material and let it sweat for 3-6 hours, then store and sprout it.

(2) When removing the film: mix 50-100 ml of Jiangwenjing + 15 ml of garlic oil with 15 kg of water, and apply as a root drench, with about 200 ml of liquid per plant, then after an interval of 5—7 days, carry out another hole drench.

(3) Before and after earthing up: mix 50-100 ml of Jiangwenjing + 15 ml of garlic oil with 15 kg of water, with 400—600 ml of liquid per plant, then after an interval of 5—7 days, carry out another hole drench.

(4) Crop rotation: crop rotation is an important way to cut off soil pathogens, especially for plots that have already developed the disease, which must be left for more than 3 years before ginger can be planted again. For planting ginger, it is best to use a new plot or a plot whose previous crop was a grain crop. In mountain villages, plots whose previous crop was sweet potato or cassava are suitable. Plots where solanaceous crops (such as tomato or chili pepper) have been planted, especially plots where bacterial wilt has occurred, are not suitable for planting ginger.

(5) Fertilizer and water management: during topdressing and watering in the growing period, make sure that ginger bacterial wilt pathogens are not introduced. Treat fertilizers with fungicides or use pathogen-free fertilizers such as soybean cake.

2. Treatment of ginger bacterial wilt

Agents with relatively good effects on ginger bacterial wilt include Jiangwenning, Genfuling, Subu, Tonggaoshang, Kejunkang, and others. Once scattered diseased plants are found, apply the treatment to the whole field in time, alternately using bactericidal solutions to drench the roots, once every 7 days, for 3~4 consecutive applications, which can effectively control the spread of ginger bacterial wilt.

Warm reminder: The epidemic period of ginger bacterial wilt is long, generally starting in June, with the peak period from July to August, and gradually weakening after September. The time of onset and its severity are related to the temperature and rainfall of that year. The suitable temperature for pathogen development is 26-31°C. The higher the temperature, the faster the disease spreads, especially in hot and rainy seasons, when the pathogen multiplies in large numbers and spreads with water, which can cause a large number of plants to develop the disease in a relatively short time. Therefore, if hot and rainy weather occurs during the disease season, the disease is severe; if the temperature is relatively low and rainfall is relatively low, the disease is often relatively mild.