| Autor: |
Clouse KM; Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS 66045.; Kansas Biological Survey & Center for Ecological Research, University of Kansas, Lawrence, KS 66045., Ellis ML; Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS 66045.; Kansas Biological Survey & Center for Ecological Research, University of Kansas, Lawrence, KS 66045., Ford NE; Department of Plant Science, Pennsylvania State University, University Park, PA 16802., Hostetler R; Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS 66045., Balint-Kurti PJ; Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC 27695.; Plant Science Research Unit, Agricultural Research Service, United States Department of Agriculture, Raleigh, NC 27695., Kleiner M; Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695., Wagner MR; Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS 66045.; Kansas Biological Survey & Center for Ecological Research, University of Kansas, Lawrence, KS 66045. |
| Abstrakt: |
Heterosis or hybrid vigor refers to the superior phenotypes of hybrids relative to their parental inbred lines. Recently, soil microbes were identified as an environmental driver of maize heterosis. While manipulation of the soil microbial community consistently altered heterosis, the direction of the effect appeared to be dependent on the microbiome composition, environment, or both. Abiotic factors are well-known modifiers of heterosis expression, however, how the interactive effects between the soil microbial community and abiotic factors contribute to heterosis are poorly understood. To disentangle the proposed mechanisms by which microbes influence heterosis, we characterize the variation in heterosis expression when maize was grown in soil inocula derived from active maize farms or prairies. While we did not observe consistent differences in heterosis among plants grown in these inocula, our observations reaffirm that microbial effects on heterosis are likely specific to the local microbial community. The introduction of a nutrient amendment resulted in greater heterosis expression in the presence of an agricultural inoculum but not a prairie inoculum. We also observed an effect of soil inocula and nutrient treatment on the composition of bacterial and fungal communities in the root endosphere. In addition, the interaction between soil and nutrient treatment significantly affected bacterial community composition, whereas fungal community composition was only marginally affected by this interaction. These results further suggest that the soil microbial community plays a role in maize heterosis expression but that the abiotic environment is likely a larger driver. |
