Table 4.
The chlorophyll fluorescence characteristics of maize.
| Year | Treatment | Fv/Fm | ΦPSⅡ | qP | qN | ETR | |
|---|---|---|---|---|---|---|---|
| 2019 | M | 0.696 ± 0.031a | 0.219 ± 0.003e | 0.337 ± 0.019a | 0.719 ± 0.046a | 116.35 ± 9.325d | |
| The border row | I | 0.697 ± 0.030a | 0.342 ± 0.01abc | 0.338 ± 0.009a | 0.721 ± 0.032a | 157.126 ± 13.966a | |
| RI | 0.709 ± 0.039a | 0.354 ± 0.007ab | 0.339 ± 0.003a | 0.747 ± 0.046a | 154.918 ± 8.066ab | ||
| RI2 | 0.685 ± 0.015a | 0.332 ± 0.028abc | 0.329 ± 0.010a | 0.752 ± 0.046a | 154.562 ± 6.768ab | ||
| RI3 | 0.681 ± 0.019a | 0.361 ± 0.015a | 0.305 ± 0.008b | 0.743 ± 0.032a | 155.717 ± 6.513ab | ||
| The middle row | I | 0.658 ± 0.014a | 0.320 ± 0.009c | 0.341 ± 0.010a | 0.717 ± 0.031a | 144.114 ± 9.287ab | |
| RI | 0.651 ± 0.008a | 0.326 ± 0.021bc | 0.318 ± 0.014a | 0.763 ± 0.018a | 145.003 ± 9.332ab | ||
| RI2 | 0.680 ± 0.015a | 0.337 ± 0.024abc | 0.341 ± 0.009a | 0.754 ± 0.024a | 139.438 ± 6.777bc | ||
| RI3 | 0.719 ± 0.014a | 0.292 ± 0.010d | 0.279 ± 0.018b | 0.744 ± 0.033a | 125.904 ± 5.66cd | ||
| 2020 | M | 0.740 ± 0.021a | 0.244 ± 0.008d | 0.361 ± 0.019ab | 0.838 ± 0.009a | 138.007 ± 7.54d | |
| The border row | I | 0.752 ± 0.009a | 0.344 ± 0.013a | 0.353 ± 0.012ab | 0.797 ± 0.008a | 164.787 ± 6.527abc | |
| RI | 0.769 ± 0.014a | 0.328 ± 0.005ab | 0.367 ± 0.021a | 0.818 ± 0.017a | 172.468 ± 7.677ab | ||
| RI2 | 0.751 ± 0.014a | 0.322 ± 0.009ab | 0.358 ± 0.019ab | 0.817 ± 0.018a | 171.407 ± 1.793ab | ||
| RI3 | 0.753 ± 0.032a | 0.325 ± 0.015ab | 0.328 ± 0.007bc | 0.815 ± 0.033a | 174.882 ± 6.019a | ||
| The middle row | I | 0.751 ± 0.033a | 0.317 ± 0.013ab | 0.338 ± 0.004ab | 0.820 ± 0.026a | 155.194 ± 4.455c | |
| RI | 0.745 ± 0.024a | 0.327 ± 0.02ab | 0.346 ± 0.019ab | 0.805 ± 0.026a | 160.225 ± 7.473bc | ||
| RI2 | 0.756 ± 0.016a | 0.302 ± 0.021bc | 0.351 ± 0.037ab | 0.835 ± 0.016a | 154.936 ± 6.666c | ||
| RI3 | 0.743 ± 0.016a | 0.283 ± 0.015c | 0.299 ± 0.009c | 0.834 ± 0.035a | 133.741 ± 11.407d | ||
M, sole maize; I, maize–peanut intercropping; RI, maize–peanut rotation–intercropping, RI2, 20% N reduction for maize of RI; ICN3, 40% N reductions for maize of RI.
The parameters are: Fv/Fm (optimal/maximal photochemical efficiency of PSII in the dark), ΦPS II (actual photochemical efficiency of PS II in the light), qP (Photochemical quenching), qN (Non-photochemical quenching) and ETR (electron transport rate). Different lowercase letters represent signifificant (P<0.05).