Performance of spring barley in an organic mixed crop rotation

Summary

A two-year field experiment with spring barley in an organic mixed crop rotation showed contrasting results between the two years in the response to the tested factors: Variety, location in the crop rotation, and organic manure application. The yields of the varieties differed due to attacks of different airborne leaf diseases. In one of the years the “high fertility” position of the barley the 1st year after grass-clover gave unexpectedly lower grain yields than the position four years after grass-clover.
Finally, the straw-based farmyard manure (FYM) resulted in higher grain yields in one of the years whereas slurry performed best in the other year, though the content of ammonia-N was less in FYM both years. We measured differences in the root development between the tested varieties indicating different potentials for nutrient uptake. The spring barley performance appeared to be very sensitive to external growth factors like climate and leaf diseases. The results stress the importance of the actual growth conditions when spring barley performance is evaluated.