How to prevent and control seed rot after sowing spring peanuts
After sowing spring peanuts and before emergence, seed rot often occurs, with severe cases reaching a rot rate as high as 20%, causing missing plants and broken rows to varying degrees. Causes of seed rot: poor seed quality or improper storage, or too long a storage period; low-lying terrain, heavy clay soil, poor texture, and high soil water content, resulting in a long emergence time for seeds; poorly consolidated seedbed preparation, which affects the...
After sowing spring peanuts and before emergence, seed rot often occurs, with severe cases reaching a rot rate as high as 20%, causing missing plants and broken rows to varying degrees.
Causes of seed rot: poor seed quality or improper storage, or too long a storage period; low-lying terrain, heavy clay soil, poor texture, and high soil water content, resulting in a long emergence time for seeds; poorly consolidated seedbed preparation, which affects the seeds' absorption of water and leads to weak seedlings; seeds not carefully selected, uneven in size, sowing not fine or uneven in depth, causing uneven emergence or missing plants and broken rows; continuous cropping for many years without rotation, severe seedling-stage diseases, causing missing plants and broken rows; application of insufficiently decomposed organic fertilizer or excessively high fertilizer concentration, causing fertilizer damage and affecting emergence; prolonged low temperature, causing delayed germination and emergence and resulting in seed rot.
Control methods: (1) Careful seed selection. Use new peanut seeds, harvest seed peanuts at the proper time and dry them promptly, and store them scientifically. Before sowing, dry the seeds with the shells on to speed up peanut metabolism, enhance seed permeability, and improve the seeds' water absorption capacity. Shell the seeds 1-3 days before sowing, and select large, undamaged seeds with un-germinated radicles for sowing. (2) Seed dressing with chemicals. Dress seeds with 50% thiophanate-methyl or 50% carbendazim wettable powder at 0.1% of seed weight to prevent seedling-stage diseases. You can also mix in 50% phoxim emulsifiable concentrate at 0.2% of seed weight to control underground pests as well as bird and rodent damage. (3) Fine sowing. The sowing depth should be 4-6 cm, and contact between seeds and fertilizer should be avoided. Using plastic film mulching cultivation can raise the soil temperature by 2°C-3°C; after sowing, the seeds germinate and emerge quickly, which can reduce disease occurrence.