TY - JOUR T1 - Outcome variation in maize interaction with arbuscular mycorrhizal fungi is correlated with extent of extra-radical mycelium JF - bioRxiv DO - 10.1101/042028 SP - 042028 AU - Ruairidh J. H. Sawers AU - Simon F. Svane AU - Clement Quan AU - Mette Grønlund AU - Barbara Wozniak AU - Mesfin Nigussie Gebreselassie AU - Matthais Mueller AU - Eliécer González-Muñoz AU - Ricardo A. Chávez Montes AU - Ivan Baxter AU - Jerome Goudet AU - Iver Jakobsen AU - Uta Paszkowski Y1 - 2016/01/01 UR - http://biorxiv.org/content/early/2016/03/01/042028.abstract N2 - In light of the rising cost and often limited access to agricultural fertilizers, arbuscular mycorrhizas are attracting ever greater interest for their potential to promote more efficient use of the world’s mineral resources. This potential remains largely unrealized, in part because of a lack of understanding of the factors determining the outcome of the symbiosis in any given context, and it remains to be demonstrated to what extent host genetic variation can drive the symbiosis in the direction of greater plant benefit under agricultural conditions. In this work, a panel of maize inbred lines, selected to maximize genetic diversity, was evaluated with and without inoculation with mycorrhizal fungi. In addition to measuring plant growth, fungal morphology, transfer of phosphorus to the plant, plant element profiles and accumulation of transcripts encoding the PHT1 family of plant phosphate transporters were also characterized. The relative performance of lines changed between non-inoculated and inoculated plants and it is proposed that such genotype x inoculation interaction is indicative of variation in host capacity to profit from symbiosis per se, and not only the result of differences in tolerance of low phosphate availability. The greatest growth response, observed in the line Oh43, was correlated with low arbuscule abundance but extensive development of extra-radical mycelium and fungal P transfer. The data suggest that host genetic factors influence fungal growth strategy with subsequent impact on the outcome of the symbiosis.Summary Corn varieties that promote greater extra-radical growth of symbiotic arbuscular mycorrhizal derive greater benefit from the interactionFunding This work was supported by the Swiss National Science Foundation ‘professeur boursier’ grants PP00A-110874, PP00P3-130704, by the Gatsby Charitable Foundation grant RG60824, by The Danish Council for Independent Research, Technology and Production Sciences grant 0602-01412B and by the Mexican National Council of Science and Technology (CONACYT) grant CB2012-151947. ER -