Effective control methods for ginger stem base rot
In recent years, with the continuous expansion of continuous ginger cropping areas, combined with extensive field management, ginger diseases have also shown a worsening trend, especially since June, due to high temperatures and frequent rain, ginger stem base rot is most likely to occur. Recently, Li Hualiang and Lu Changlei from Renzhao Town, Pingdu City, Shandong Province, and Yu Wanquan from Ju County and others reported that in their area...
In recent years, with the continuous expansion of continuous ginger cropping areas, combined with extensive field management, ginger diseases have also shown a worsening trend, especially since June, due to high temperatures and frequent rain, ginger stem base rot is most likely to occur. Recently, Li Hualiang and Lu Changlei from Renzhao Town, Pingdu City, Shandong Province, and Yu Wanquan from Ju County and others reported that the ginger planted in their area has already begun to show stem base rot, and they are seeking good control methods. They are introduced as follows:
1. Disease symptoms
In the early stage of ginger stem base rot, water-soaked spots of varying sizes appear at the stem base, gradually expanding, and the leaves turn yellow. In the late stage of the disease, the lesions encircle the stem base for one full circle, causing the tissue at the stem base to gradually rot. Because the transport of water and nutrients is blocked, the aboveground main stem dries up and dies from top to bottom, the leaves turn black and fall off, showing a withered appearance. When humidity is high, if the soil is pushed aside, white cotton-like material can be seen on the diseased parts and in the soil. In severe cases, plants begin to die, causing great harm.
2. Transmission routes
The pathogen overwinters as mycelium lurking on diseased ginger and diseased residues, or overwinters in the soil as mycelium and chlamydospores, and can cause disease when conditions are suitable. It generally begins to occur in May, and after harvest, seed ginger carrying the pathogen can continue to develop the disease, continuing until sowing in March of the following year.
3. Conditions for disease occurrence
High temperature and high humidity favor the occurrence of ginger stem base rot, and the suitable temperature for disease development is 20°C-25°C. Ginger is a light-loving and drought-tolerant plant, and plots with poor ventilation and light penetration are prone to the disease. Yellow clay loam and heavily clayey soils have severe disease occurrence. It is advisable to choose sandy loam with deep soil layers, good drainage, loose texture, and rich organic matter. The suitable soil pH is 6-7. Phosphorus and potassium fertilizers can effectively promote ginger growth and improve disease resistance. The pathogen can survive in the soil for a long time, and in continuous cropping plots, the accumulation of inoculum in the field leads to more severe disease.
4. Control methods
1. Select disease-free, pest-free, and non-moldy seed ginger to prevent the spread of diseases and pests and ensure full and strong seedlings. When sowing, soak the seeds in 8000-fold dilution of 40% Fuxing emulsifiable concentrate, or use 200 g of 50% carbendazim per 100 kg of seeds mixed with 100 kg of water, soak for 4-5 minutes, dry, and then sow.
2. Soil disinfection treatment. In plots with severe disease occurrence, when preparing the land, apply 1-1.5 kg of 70% thiophanate-methyl, 50% carbendazim, 50% dichlone, or thiram per mu mixed with 30 kg of fine soil and broadcast it into the soil. Apply lime for disinfection in acidic soil, which can prevent soilborne diseases.
3. Reasonable crop rotation. Rotate with gramineous crops for more than 2 years to prevent disasters and avoid harm.
4. Scientific fertilization and soil improvement. Ginger prefers soil with good aeration. Per mu, use 100 kg of potassium sulfate-type no-till fertilizer and 2500 kg of well-decomposed farmyard manure, 1 kg of Boron Jiajia, and 1.5 kg of Zinc Jiajia.
5. Ridge cultivation with trellis support improves soil aeration and promotes underground stem growth. Make ridges 1 m wide and 20 cm high. When seedlings are 30 cm tall, set up A-shaped trellises with 4 bamboo poles per sq m to promote ventilation, light penetration, and moisture flow, promote leaf photosynthesis, and prevent and control disease.
6. In the early stage of disease, drench the roots or spray the leaves with 250-fold dilution of Duoyongtu plus natural brassinosteroid - Shuofeng 481. Alternatively, use 8000-fold dilution of 40% Fuxing emulsifiable concentrate or 1000-fold dilution of 75% chlorothalonil to drench the roots at the diseased parts, 50-100 ml per plant, once every 10 days, for 2 consecutive applications.