Auswirkungen der Züchtung bei Winterweizen in einem landwirtschaftlichen System mit geringer Betriebsmittelzufuhr von außen

Abstract

Abstract Impact of Wheat Breeding in an Agricultural Low External Input System Low external input systems, e.g. ecological agriculture, are able to solve problems concerning environmental pollution, diminishing ressources, and overproduction. Since growing conditions of winter wheat are very different in ecological agriculture as compared to conventional systems, the impact of genetic improvement of winter wheat in low external input systems is not well known. Investigations were carried out in two years at two ecologically managed farms using 24 genotypes of winter wheat of different periods of release (about 1900 to 1983). The results can be summarized as follows:1. The tendency towards higher yields among modern varieties as compared to older cultivars in ecological agriculture was highly significant.2. The rate of yield improvement was smaller under low external input as compared to conventional conditions results. Yield improvement was greatest in recent decades.3. In ecological agriculture higher yields among modern varieties resulted from an increased harvest index along with an unchanged biomass production, improved resistance properties, and higher ear weight. Reduced plant height probably has negative effects.4. Baking quality was improved clearly by wheat breeding.5. Further genetic improvement of winter wheat yields in low external input systems may result from increased biomass production along with a constant or enhanced harvest index, improved resistance properties, increased plant height, and pronounciation of ear weight.