Fig 1.
Effects of exogenous addition with PHY and PSB on plant height (a), stem diameter (b), dry matter (c) and P uptake (d) of maize with or without application organic P in low-P red soil.
Values with the same lower-case letters are not significantly different among different P sources and exogenous addition treatments at the 5% level by the LSD. -Po represents that no organic P was applied, Po represents that organic P was applied. CK is control, PHY represents addition of phytase, PSB represents addition of phosphorus-solubilizing bacteria. the same as below.
Table 1.
Effects of exogenous addition with PHY and PSB on root morphological traits of maize with or without application organic P in low-P red soil.
Fig 2.
Effects of exogenous addition with PHY and PSB on pH (a), Olsen-P (b), SOM (c), availzble N (d), available K (e) and total P (f) of maize with or without application organic P in low-P red soil.
Values with the same lower-case letters are not significantly different among different P sources and exogenous addition treatments at the 5% level by the LSD. -Po represents that no organic P was applied, Po represents that organic P was applied. CK is control, PHY represents addition of phytase, PSB represents addition of phosphorus-solubilizing bacteria. the same as below.
Fig 3.
Effects of exogenous addition with PHY and PSB on mycorrhizal colonization (a), ACP (b), ALP (c) and phytase (d) of maize with or without application organic P in low-P red soil.
Values with the same lower-case letters are not significantly different among different P sources and exogenous addition treatments at the 5% level by the LSD. -Po represents that no organic P was applied, Po represents that organic P was applied. CK is control, PHY represents addition of phytase, PSB represents addition of phosphorus-solubilizing bacteria. the same as below.
Table 2.
Effects of exogenous addition with PHY and PSB on P fractions of maize rhizosphere soil with or without application organic P in low-P red soil.
Fig 4.
Effects of exogenous addition with PHY and PSB on labile P pool (a), moderately-labile P pool (b), non-labile P pool (c), organic P pool (d) and inorganic P pools (d) in rhizosphere soil of maize with or without application organic P in low-P red soil.
Values with the same lower-case letters are not significantly different among different P sources and exogenous addition treatments at the 5% level by the LSD. -Po represents that no organic P was applied, Po represents that organic P was applied. CK is control, PHY represents addition of phytase, PSB represents addition of phosphorus-solubilizing bacteria. the same as below.
Fig 5.
Correlations between the root characteristics and P uptake, agronomic traits (a), soil physical and chemical indexes, enzyme activity and available P (b) by the redundancy analysis.
The red arrow indicates the explanatory variable, and the black arrow indicates the response variable. MC represents mycorrhizal colonization, ACP represents acid phosphatase. ALP represents alkaline phosphatase, AN represents available nitrogen, AK represents available potassium. the same as below.
Fig 6.
Mantel analysis (a) and correlation analysis (b) of P fractions, P pool and agronomic traits, root characteristics, soil physical and chemical, enzyme activity in rhizosphere soil of maize in low-P red soil.