Corn hybrid Pioneer 30K75 was planted with narrow row of 45 cm width with the treatments shown in the table below with respective results.

Treatments	At planting (kg/ha)			Pre-plant, broadcast (kg/ha)	Knifed pos-planting (kg/ha)	Total nutrients (kg/ha)	Yield corn grain
	Fertilizers	N	P2O5	K2O	N	(N-P2O5-K2O)	kg/ha
1	400 08-30-12	32	120	100	100	132-120-148	9,162
2	444 Yoorin N32S + 41 urea	32	120	148	100	132-120-148	9,552
3	280 Gafsa+66 MAP+56 urea	32	120	148	100	132-120-148	8,952
4	400 08-30-12 + 222 urea	132	120	100	0	132-120-148	11,376
5	444 Yoorin N32S + 263 urea	132	120	148	0	132-120-148	9,684
6	280 Gafsa+66 MAP+278 urea	132	120	148	0	132-120-148	9,504

The response to additional N at planting time can be seen comparing treatment 4 with treatment 1: an increase of 2,214 kg/ha just by changing the placement, not the total amount of N. Another interesting effect was the better response for more N at planting row with soluble P than with Gafsa or Yoorin (thermophosphate).