ABSTRACT
FERTILIZER EXPERIMENTS WITH RAPE IN A MAIPO LOAM SOIL

Inés Sotomayor R.1
 

The effect of different fertilizer treatments on rape production was studied in three field experiments. These were conducted al La Platina Experiment Station (Santiago, Chile), under irrigated conditions, on a Maipo loam soil, with pH 8.1.
Results indicated a considerable response to nitrogen, but no to phosphorus, in spite of a low phosphorus availability in the soil as indicated by soil testing.
Rates of 75 to 150 Kg of N per hectare were necessary to obtain high yields of rape, depending on the nitrogen availability in the soil. Increasing nitrogen fertilizer rates slightly reduced oil percent in the rape seed, butthis was more thancompensated by the increase in the yeild of seed.
There was no difference in the effect of urea with respect to chilean nitrate (sodium nitrate) as sources of N.
No difference was observed between applying these fertilizers in one application at planting time, or splitting it one haH at planting time and the other half before flowering.

Keywords:
1Ing. Agr., Programa Fertilidad de Suelos, Estación Experimental La Platina, Instituto de Investigaciones Agropecuarias, Casilla 5427, Santiago, Chile.