S. sclerotiorum is a common disease on soybean crops, which mainly causes stalk rot, lesions are pale, and stems are hollow and have black sclerotia, easily broken. In the past two years, S. sclerotiorum has been increasing year by year. Edible Starch Mixer,Starch Mixer,Coupling Starch Mixer,Yam Starch Mixer Shuangfeng County Dingyuan Machinery Manufacturing Co. Ltd.. , http://www.starchseparator.com
Causes and characteristics:
1. The number of sclerotia in the field is greater than that of soybean sclerotium. The genus is a fungus that forms a cylindrical or murine sclerotia on the stem of soybeans. Its shape is irregular, and the size is 1 to 4 mm and 3 to 7 mm. The sclerotia is in a rainy, moist environment. Germination occurs under light conditions, pathogenic fungi scattered in the soil and sclerotia mixed in the seeds overwinter, the seeds can also be carried.
2. Environmental factors During the flowering period of soybean, the soil surface temperature is high, air humidity is high, and rainfall is large, which is favorable to the occurrence of this disease.
3. Seed-carrying sclerotia If soybeans are harvested as seeds for the previous year in successive years, the sclerotia residue in the seeds may increase, resulting in an increase in the incidence of S. sclerotiorum.
4. Improper cultivation and management. Planting of high-density plots of soybean sclerotia occurs heavy. The reason is that excessive dense planting will cause poor ventilation, excessive humidity, which is conducive to the onset of disease; the occurrence of soybean sclerotia in the land adjacent to sunflowers and rapeseed is heavy; in addition, the occurrence of soybean sclerotia disease is heavy in the land that is heavily planted.
Control measures:
1. Rational rotation for soybean sclerotinia spread only harm soybean, sunflower, rape, does not infect the grass crops. Therefore, it is necessary to reform the farming system and implement rotations for more than three years to avoid being adjacent to sunflower and rapeseed and to control the spread of S. sclerotiorum.
2. Select seeds before sowing should be screened in addition to mixed sclerotia in soybean seeds, sterile seed selection of sterile seeds.
3. Strengthen the cultivation and management of reasonable dense planting, row silt treatment, planting the land, draining the ditch, prevent the spread of water and flowing water, and shovel the earthworms in time before the soybeans are ridged to eliminate the germinating sclerotia and the apium plate. Severely affected soybeans should be deep-rooted after harvest and the diseased bodies and sclerotia should be turned underground.
4. Chemical control In the soybean flowering stage, the soybean nucleus just begins to germinate to the ascendant plate to form a flourishing stage. Spray 50% Suo Keling wettable powder 1500 times liquid on the ridge table soil surface, or spray 50% nongrill wettability. The powder 1000 times liquid 30 kilograms, the plots that sprayed the above-mentioned medicaments control the soybean sclerotinia disease effect can reach above 85%.
Author: Heilongjiang Province Suihua City Agricultural Technology Extension Station