Die Bodenkultur - Journal for Land Management, Food and Environment


Effects of changing row density and seed rate of winter wheat on plant growth and grain yield in order to implement injection of liquid manure in standing cereal crops


Field experiments with winter wheat had been conducted on two locations in the Rhineland in Germany (1988 until 1991) concerning the nitrogen fertilization of cereal crops with liquid manure (pig slurry). In order to apply the liquid manure through injection (knifing in) into the standing crop some of the rows of the crop plants should not be sown. Objective of the research was to determine the effects of missing crop rows onto canopy development and grain yield.

For the examined locations having higher nutrient supply there was no yield difference when applying the liquid manure through injecting it into the soil either in every other or in every third missing crop row (used row distance: 12.5 cm).

It was not necessary to alter the site optimal seed rates when changing number of rows. Reduced sowing rates could lead to the risc of yield losses in some years.

The development of the crop stand is not affected negatively when having missing rows. Distributing the same seed rate onto fewer rows leads to increased plant competition within the row. This has in effect a reduced number of ears per plant, higher kernel numbers and increased grain weight per ear and thus enhances growth of the individual plant within the crop population. Through such an enhancement of the single plant these crop stands can have so some extend higher yields than with full row number.

Reducing the distance between plants within the row when having missing rows increased to susceptability to powdery mildew during grain filling.

Key words: fertilization with slurries, crop stand, seed rate, wheat, crop yield.