What kind of fertilizer should be used to increase the yield and income of corn seedlings?

1. Base fertilizer (the most crucial) 

Compound fertilizer (15-15-15) or corn-specific fertilizer: 40-50 pounds per acre. 
- Add 10 kilograms of potassium chloride to enhance plant growth and prevent lodging. 
Function: Strong and healthy stems, robust growth, good root system 

2. Seedling fertilizer (at 4-6 leaves stage) 

A small amount of urea: 10 to 15 kilograms per acre. 
Function: Promotes growth, early emergence of shoots, and prevents yellowing of leaves. 

3. Large trumpet-shaped leaves (9th to 12th leaves, determining yield) 

Urea: 20-25 kilograms + Potassium fertilizer: 10-15 kilograms 
Function: Large stem, numerous grains, no blunt tip, full grains 

4. Grouting Foliar Fertilizer (The Magic Formula for Yield Increase) 

Potassium dihydrogen phosphate + Nematicide spray 
Function: High grain weight, no premature aging, significant yield increase 

Remember it in one sentence 

The base fertilizer should be abundant, the seedling fertilizer should be light, the fertilizer for the flowering stage should be heavy, and phosphorus and potassium should be sprayed in the later stage. 
Nitrogen is the main nutrient, followed by potassium. With a large and plump corn cob, you can achieve greater harvest and higher income.