Year: 2020
Type: article
Abstract: Plants and soil microorganisms interact closely in the rhizosphere where plants may exchange carbon (C) for functional benefits from the microbial community. For example, the bioenergy crop, switchgrass ( Panicum virgatum ) is thought to exchange root-exuded C for nitrogen (N) fixed by diazotrophs (free-living N-fixers). However, this interaction is not well characterized and it is not known how or if switchgrass responds to diazotrophs or their activity. To explore this question, we assessed rhizosphere metabolite chemistry of switchgrass grown in a hydroponic system under two N levels and under inoculated or uninoculated conditions. We found switchgrass root exudate chemistry to be more responsive to N availability than to diazotroph presence. Total metabolite concentrations were generally greater under high N versus low N and unaffected by inoculation. Examination of rhizosphere chemical fingerprints indicates metabolite chemistry was also driven strongly by N availability with a greater relative abundance of carbohydrates under high N and greater relative abundance of organic acids under low N. We also found evidence of changes in rhizosphere chemical fingerprints by inoculation treatment suggesting a potential for switchgrass to respond or even recruit diazotrophs. However, we found little evidence of N treatment and inoculation interaction effects which suggests switchgrass response to diazotroph presence is not mediated by N availability.
Source: Phytobiomes Journal
Language: English
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: gold
Estimated APC paid: $1,660
Awards: GREAT LAKES BIOENERGY RESEARCH CENTER, G1202769797, G125460123, G1286236842, G1337544421, G1375765430, G1592975470, G1648283888, G1863003419, G222180108, G223002938, CONNECTING NITROGEN TRANSFORMATIONS MEDIATED BY THE RHIZOSPHERE MICROBIOME TO PERENNIAL CROPPING SYSTEM PRODUCTIVITY IN MARGINAL LANDS, G2506945562, G2510423872, G2820049545, G2988778103, G3083819904, G3193070969, LTER: KBS - Mechanisms of Resilience in Agricultural Landscapes, G3444752832, G3508161151, CONNECTING NITROGEN TRANSFORMATIONS MEDIATED BY THE RHIZOSPHERE MICROBIOME TO PERENNIAL CROPPING SYSTEM PRODUCTIVITY IN MARGINAL LANDS, GREAT LAKES BIOENERGY RESEARCH CENTER, G419881185, G42916606, GREAT LAKES BIOENERGY RESEARCH CENTER, G4501827968, G455569901, G498139845, G5373841109, G5653134238, G5742687135, G5932669461, G5983990188, G6657702422, G7205239661, G7350903426, G7432929840, G7560550554, G7562546725, G7673727097, TAS::89 0227:: TAS RECOVERY ACT - BIOENERGY RESEARCH CENTER CAPITAL EQUIPMENT - GLBRC, G7787287669, G7913850483, TAS::89 0227:: TAS RECOVERY ACT - BIOENERGY RESEARCH CENTER CAPITAL EQUIPMENT - GLBRC, G821644656, G834277795, GREAT LAKES BIOENERGY RESEARCH CENTER, G8758233399, G969889393
OpenAlex ID: W3010294298