title: Nutrient use efficiency and arbuscular mycorrhizal root colonisation of winter wheat cultivars in different farming systems of the DOK long-term trial.
abstract: BACKGROUND
  For organic farming, cultivars are required with high nutrient use efficiency under nutrient limited conditions. Arbuscular mycorrhizal fungi (AMF) are known to contribute to nutrient uptake under low input conditions. We compared nutrient use efficiency (NUE) of old and modern organically and conventionally bred cultivars in organic and conventional systems and assessed AMF-root colonisation (AMF-RC) in relation to nutrient concentrations.
  
  
  RESULTS
  Cultivars and systems had a statistically significant effect on nitrogen (N) and phosphorus (P) concentrations and NUE parameters, whereas no genotype x environment interactions appeared. In contrast to N and P uptake, the NUE parameters were higher under organic than under conventional conditions. NUE for N increased with the year of release of cultivars. In the organic systems, the organically bred cultivars could not outperform the conventionally bred cultivars in grain yield and NUE parameters. AMF-RC was higher in the organic than in the conventional system, but did not differ among cultivars.
  
  
  CONCLUSIONS
  Cultivars achieving high NUE in the organic systems were found among modern cultivars, irrespective of the breeding programme. Nutrient conditions during the breeding programme did not affect AMF-RC. No clear evidence was found that AMF symbiosis contributed more to nutrient concentrations under low input than under high input conditions.
authors.affiliation: Research Institute of Organic Agriculture FiBL, Ackerstrasse, 5070 Frick, Switzerland. isabell.hildermann@fibl.org
authors.forename: Isabell
authors.initials: I
authors.lastname: Hildermann
authors.forename: Monika
authors.initials: M
authors.lastname: Messmer
authors.forename: David
authors.initials: D
authors.lastname: Dubois
authors.forename: Thomas
authors.initials: T
authors.lastname: Boller
authors.forename: Andres
authors.initials: A
authors.lastname: Wiemken
authors.forename: Paul
authors.initials: P
authors.lastname: Mäder
mesh_terms: D000383:Agriculture / Q000379:methods*; D001947:Breeding / Q000379:methods*; D018556:Crops, Agricultural / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D058870:Food, Organic; D005838:Genotype; D038821:Mycorrhizae; D009584:Nitrogen / Q000032:analysis* / Q000378:metabolism; D010758:Phosphorus / Q000032:analysis* / Q000378:metabolism; D018517:Plant Roots / Q000382:microbiology; D013559:Symbiosis; D014908:Triticum / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism
chemical_list: D010758:Phosphorus; D009584:Nitrogen