Table 3.
The chlorophyll fluorescence characteristics of maize.
| Year | Parameters | M | I | RI | RI2 | RI3 | ||||
|---|---|---|---|---|---|---|---|---|---|---|
| BR | MR | BR | MR | BR | MR | BR | MR | |||
| 2019 | Rd | 5.24 | 6.00 | 5.74 | 5.86 | 5.53 | 5.73 | 5.46 | 5.62 | 5.59 |
| Icomp | 119.16 | 136.96 | 132.22 | 141.03 | 133.96 | 134.97 | 135.11 | 137.38 | 121.94 | |
| Isat | 1773.63 | 1768.51 | 1778.92 | 1820.63 | 1762.28 | 1776.27 | 1763.38 | 1789.06 | 1684.72 | |
| Pnmax | 41.95 | 47.25 | 45.24 | 46.62 | 45.42 | 46.03 | 44.81 | 45.71 | 43.46 | |
| R2 | 99.63% | 99.51% | 99.63% | 99.70% | 99.73% | 99.86% | 99.80% | 99.83% | 99.44% | |
| ITI | 21293.21 | 23697.65 | 22575.53 | 23967.74 | 22565.57 | 23858.00 | 21997.08 | 23529.34 | 22529.50 | |
| IPI | 2571.05 | 4965.91 | 4378.37 | 4942.22 | 4345.35 | 5051.74 | 4419.44 | 5084.67 | 4466.50 | |
| IBI | 1940.76 | 2564.30 | 2467.49 | 2464.24 | 2346.37 | 2517.96 | 2391.01 | 2558.03 | 2429.45 | |
| II | 18698.04 | 20472.36 | 19459.33 | 20803.46 | 19544.64 | 20674.77 | 18974.54 | 20309.53 | 19429.68 | |
| 2020 | Rd | 5.23 | 6.00 | 5.87 | 6.24 | 5.80 | 6.10 | 5.72 | 6.23 | 5.45 |
| Icomp | 135.98 | 148.45 | 150.56 | 153.60 | 146.96 | 152.95 | 151.30 | 152.53 | 123.00 | |
| Isat | 1781.62 | 1793.32 | 1794.83 | 1783.12 | 1786.92 | 1795.22 | 1772.45 | 1784.93 | 1747.73 | |
| Pnmax | 43.07 | 46.54 | 45.16 | 46.02 | 44.78 | 45.87 | 43.52 | 44.77 | 41.48 | |
| R2 | 99.59% | 99.38% | 99.60% | 99.36% | 99.60% | 99.59% | 99.75% | 99.41% | 99.64% | |
| ITI | 21396.48 | 23731.01 | 22697.79 | 23679.83 | 22365.27 | 24019.29 | 22704.76 | 23419.74 | 22230.69 | |
| IPI | 3091.13 | 5417.59 | 4877.30 | 5341.33 | 4802.37 | 5514.74 | 4924.01 | 5491.01 | 4884.41 | |
| IBI | 2608.65 | 2962.89 | 2881.67 | 2993.10 | 2894.30 | 3084.18 | 2989.68 | 2890.24 | 2790.90 | |
| II | 18291.11 | 20252.74 | 19318.72 | 20174.34 | 18965.04 | 20408.13 | 19228.38 | 20028.28 | 18925.15 | |
M, sole maize; I, maize–peanut intercropping; RI, maize–peanut–intercropping, RI2, 20% N reduction for maize of RI; ICN3, 40% N reductions for maize of RI.
The parameters are: Dark respiration rate (Rd, μmol (CO2) m–2 s–1), light saturation point (Isat, μmol (photon) m–2 s–1), light compensation point (Icomp, μmol (photon) m–2 s–1), asymptotic estimate of the maximum gross photosynthetic rate (Pgmax, μmol(CO2) m–2 s–1). The light includes top incident light (ITI, μmol (photon) m–2 s–1) and bottom incident light (IDI, μmol (photon) m–2 s–1). The PAR includes top incident light accumulation (ITI, μmol (photon) m–2), spike leaf incident light accumulation (IPI, μmol (photon) m–2), bottom incident light accumulation (IBI, μmol (photon) m–2), and light interception accumulation (II, μmol (photon) m–2).