Root-associated endophytic fungi like Serendipita indica and arbuscular mycorrhizal(AM) fungi can improve plant growth and root construction, but the potential mechanism is unclear. In this study, Funneliformis mossea...Root-associated endophytic fungi like Serendipita indica and arbuscular mycorrhizal(AM) fungi can improve plant growth and root construction, but the potential mechanism is unclear. In this study, Funneliformis mosseae(an AM fungus) and S. indica, singly or in combination were inoculated into trifoliate orange(Poncirus trifoliata) seedlings, to assess changes in biomass and root morphological traits, coupled with auxins and cytokinins concentrations in leaves and roots and the expression of auxin synthesis and transporter protein genes. After 20 weeks of inoculation with these fungi, shoot and root biomass, root total length, taproot length, average diameter, surface area, volume, and the number of lateral roots in 1st-, 2nd-, and 3rd-order were improved, and S. indica showed a relatively greater effect than F. mosseae and dual inoculation. Endophytic fungal inoculation also significantly increased the concentration of indoleacetic acid, indole butyric acid, trans-zeatin,dihydrozeatin, and isopentenyl adenine in leaves and roots, whilst F. mosseae and S. indica exhibited relatively greater effects on leaves and roots, respectively. Correlation analysis revealed that both biomass and root morphological traits(except root projected area) were significantly positively associated with endogenous auxins and cytokinins. In addition, the inoculated plants recorded comparatively higher expression levels of indoleacetic acid synthesis genes(PtTAA1, PtTAR2, PtYUC3, PtYUC4, PtYUC6, and PtYUC8) and indoleacetic acid transporter protein genes(PtAUX1, PtLAX1, PtLAX2, PtLAX3, PtPIN1, PtPIN3, PtPIN4, PtABCB1, and PtABCB19) than the non-inoculated plants, among which F. mosseae and S. indica showed better effects in leaves and roots, respectively. These results suggest that root-associated endophytic fungi improved plant growth and root architecture, which were associated with changes in endogenous auxins and cytokinins.展开更多
Symbiotic fungi are involved in plant flooding tolerance,while the underlying mechanism is not yet known.Since polyamines(PAs)and proline are also associated with stress tolerance,it is hypothesized that the enhanceme...Symbiotic fungi are involved in plant flooding tolerance,while the underlying mechanism is not yet known.Since polyamines(PAs)and proline are also associated with stress tolerance,it is hypothesized that the enhancement of stress resistance by symbiotic fungi is associated with changes in PAs and/or proline.The aim of this study was to analyze the effect of inoculation with Funneliformis mosseae and Serendipita indica on plant growth,PAs,and proline and the metabolisms in peach(Prunus persica)under flooding.Two-week flooding did not affect root colonization frequence of F.mosseae,while it promoted root colonization frequence of S.indica.Under flooding,plants inoculated with F.mosseae and S.indica maintained relatively higher growth rates than uninoculated plants.Funneliformis mosseae promoted root ornithine(Orn)contentration and arginine(Arg)and Orn decarboxylase activities under flooding,which promoted putrescine(Put),cadaverine(Cad),and spermidine(Spd)contentrations.Conversely,S.indica decreased contentrations of Arg,Orn,and agmatine and Arg decarboxylase activities,thus decreasing PA contentrations under flooding.Polyamines were negatively correlated with the expression of PA uptake transporter genes,PpPUT1 and PpPUT2,in peach.Polyamine transporter genes of F.mosseae(FmTPO)and S.indica(SiTPO)were regulated by flooding,of which FmTPO1 was positively correlated with Put,Cad,and Spd,along with positive correlations of Spd with SiTPO1,SiTPO2,and SiTPO4.Under flooding,F.mosseae decreased proline concentration,while S.indica increased proline concentration and correlated with expression of a△^(1)-pyrroline-5-carboxylate synthetase gene,PpP5CS2.It was thus concluded that F.mosseae modulated polyamine accumulation,while S.indica induced proline accumulation to tolerate flooding.展开更多
基金supported by the Plan in Scientific and Technological Innovation Team of Outstanding Young Scientists,Hubei Provincial Department of Education (Grant No.T201604)。
文摘Root-associated endophytic fungi like Serendipita indica and arbuscular mycorrhizal(AM) fungi can improve plant growth and root construction, but the potential mechanism is unclear. In this study, Funneliformis mosseae(an AM fungus) and S. indica, singly or in combination were inoculated into trifoliate orange(Poncirus trifoliata) seedlings, to assess changes in biomass and root morphological traits, coupled with auxins and cytokinins concentrations in leaves and roots and the expression of auxin synthesis and transporter protein genes. After 20 weeks of inoculation with these fungi, shoot and root biomass, root total length, taproot length, average diameter, surface area, volume, and the number of lateral roots in 1st-, 2nd-, and 3rd-order were improved, and S. indica showed a relatively greater effect than F. mosseae and dual inoculation. Endophytic fungal inoculation also significantly increased the concentration of indoleacetic acid, indole butyric acid, trans-zeatin,dihydrozeatin, and isopentenyl adenine in leaves and roots, whilst F. mosseae and S. indica exhibited relatively greater effects on leaves and roots, respectively. Correlation analysis revealed that both biomass and root morphological traits(except root projected area) were significantly positively associated with endogenous auxins and cytokinins. In addition, the inoculated plants recorded comparatively higher expression levels of indoleacetic acid synthesis genes(PtTAA1, PtTAR2, PtYUC3, PtYUC4, PtYUC6, and PtYUC8) and indoleacetic acid transporter protein genes(PtAUX1, PtLAX1, PtLAX2, PtLAX3, PtPIN1, PtPIN3, PtPIN4, PtABCB1, and PtABCB19) than the non-inoculated plants, among which F. mosseae and S. indica showed better effects in leaves and roots, respectively. These results suggest that root-associated endophytic fungi improved plant growth and root architecture, which were associated with changes in endogenous auxins and cytokinins.
基金supported by the Open Fund of Engineering Research Center of Ecology and Agricultural Use of Wetland,Ministry of Education,China(No.KFT202005)。
文摘Symbiotic fungi are involved in plant flooding tolerance,while the underlying mechanism is not yet known.Since polyamines(PAs)and proline are also associated with stress tolerance,it is hypothesized that the enhancement of stress resistance by symbiotic fungi is associated with changes in PAs and/or proline.The aim of this study was to analyze the effect of inoculation with Funneliformis mosseae and Serendipita indica on plant growth,PAs,and proline and the metabolisms in peach(Prunus persica)under flooding.Two-week flooding did not affect root colonization frequence of F.mosseae,while it promoted root colonization frequence of S.indica.Under flooding,plants inoculated with F.mosseae and S.indica maintained relatively higher growth rates than uninoculated plants.Funneliformis mosseae promoted root ornithine(Orn)contentration and arginine(Arg)and Orn decarboxylase activities under flooding,which promoted putrescine(Put),cadaverine(Cad),and spermidine(Spd)contentrations.Conversely,S.indica decreased contentrations of Arg,Orn,and agmatine and Arg decarboxylase activities,thus decreasing PA contentrations under flooding.Polyamines were negatively correlated with the expression of PA uptake transporter genes,PpPUT1 and PpPUT2,in peach.Polyamine transporter genes of F.mosseae(FmTPO)and S.indica(SiTPO)were regulated by flooding,of which FmTPO1 was positively correlated with Put,Cad,and Spd,along with positive correlations of Spd with SiTPO1,SiTPO2,and SiTPO4.Under flooding,F.mosseae decreased proline concentration,while S.indica increased proline concentration and correlated with expression of a△^(1)-pyrroline-5-carboxylate synthetase gene,PpP5CS2.It was thus concluded that F.mosseae modulated polyamine accumulation,while S.indica induced proline accumulation to tolerate flooding.
