Colombi, Tino
- Department of Soil and Environment, Swedish University of Agricultural Sciences
- University of Nottingham
Abstract
Cultivar mixtures have the potential to mitigate abiotic stress and stabilize crop yields, but their belowground dynamics remain poorly understood. We evaluated phosphorus (P) uptake by two contrasting spring barley (Hordeum vulgare L.) cultivars ("Anneli" and "Feedway"), grown either in 50:50 mixture or as pure stand. The cultivars were grown in mesocosms under four P fertilization treatments: low-P, homogeneous high-P (90 mg P/kg), and localized P hotspots (100 mg P) placed either in the topsoil (5 cm) or subsoil (35 cm). To trace P uptake pathways, the hotspots were labeled with 33P and enclosed in mesh bags allowing only mycorrhizal hyphae (25 mu m) or both roots and hyphae (2 mm) to access the hotspot. After 35 days, we measured aboveground biomass, total P content, P-33 specific activity, and root biomass, length, diameter, and arbuscular mycorrhiza fungi (AMF) root colonization. In the mixture, reduced P uptake by "Feedway" led to lower overall performance compared to pure stand. Root modifications in the mixture did not enhance biomass or P acquisition, potentially due to decreased AMF colonization. Although different P placements altered P uptake patterns, they did not increase total P uptake. Roots accessed the P hotspots and acquired P-33 without notable proliferation in the enriched zones. Our findings underscore the complexity of belowground interactions involving root distribution, competition for P, and AMF, and highlight the need for future research to optimize nutrient acquisition and performance in cultivar mixtures.
Keywords
Hordeum Vulgare L.; intraspecific interactions; phosphorus distribution; phosphorus hotspot; root distribution
Published in
Physiologia Plantarum
2025, volume: 177, number: 4, article number: e70363
Publisher: WILEY
SLU Authors
Keller, Thomas
- Department of Soil and Environment, Swedish University of Agricultural Sciences
- Agroscope
- Department of Soil and Environment, Swedish University of Agricultural Sciences
UKÄ Subject classification
Soil Science
Agricultural Science
Publication identifier
- DOI: https://doi.org/10.1111/ppl.70363
Permanent link to this page (URI)
https://res.slu.se/id/publ/142985