Die Entwicklung des Ertragsniveaus im „Ewigen Roggenbau“ in Halle/S. seit 1879.

In Eternal Rye Trial of Halle/Germany the development of yields is considered for winter rye 1879-2010 and as well as corn and potatoes 1962-2010 to four fertilizer treatments based on decade averages and possible causes for changes in level are mentioned. The yields of winter rye decreased up to 1920, thereafter they remained until the 1960 years more or less constant, and then went up to the present on all variants. In the unfertilized variant, the decade average grain yield was after the start of 22.7 dt/ha, decreased to the 1920 s up to 10.7 dt/ha from and increased from the late 1960 s until the last decade again to 22.2 dt/ha. The causes of the yield drop in the first 40 years after the start of Eternal Rye were mainly in the negative effects of monoculture and the use of seed of the trial area. The yield increase since 1920 were caused mainly by cultivation of new, higher-yielding varieties, regular use of plant protection products and perhaps also by elevated atmospheric CO2 concentration. [ABSTRACT FROM AUTHOR]