Crop-weed competition and weed community shifts due to increased fertilizing in organic spring wheat

Description

Agriculture is one of the major land uses in the current age, associated with a lot of environmental impacts. Thus, the need for sustainable farming is an urgent matter. Organic farming has been suggested as a more sustainable alternative to conventional farming. However, due to lower yields the environmental benefits of organic farming are less prominent, and discussions are heavy of the to be or not to be of organic farming. Less so, the discussion focuses on the possibility of increasing organic yields without loosing its benefits. This study aimed at investigating if organic yields can be increase by higher fertilizing and if this will increase competition with weeds or sacrifice weed diversity. A field experiment in spring wheat was setup in 2022 with four levels of fertilizing, from none to a surplus. Half of the plots were then completely removed of all weeds and the other half left untouched. An interaction of fertilizing and weeding on yield was found, such that by fertilizing weed levels are increased and cause a yield loss. We can also show that by fertilizing the weed community changes, species richness is not affected during this initial year, but evenness decreases with fertilizing. This community shift increases the frequency of troublesome traits such as weed canopy height which suggests competition increases and weed problems are enhanced. In addition, the decrease in evenness by fertilizing potentially forecasts a loss of plant diversity in the long term. Achieving a higher yield in organic farming is possible, however care must be taken to investigate trade-offs between management interests and environmental impacts. More research is needed to find where trade-offs and especially synergies can be found to finally understand what is a sustainable yield level.

Period	2023 Sept 12
Event title	GfÖ Annual Meeting 2023 - 52nd Annual Meeting of the Ecological Society of Germany, Austria and Switzerland: The Future of Biodiversity – overcoming barriers of taxa, realms and scales
Event type	Conference
Conference number	52
Location	Leipzig, Germany, SaxonyShow on map