Table 4 The initial slope of the fast light curve (α, electrons photons− 1) of two cotton varieties (XLZ42 and XLZ45) at different days after flowering in various treatment groups: Mulch film was removed at 1 and 10 days before the first irrigation (respectively T1(June 19, 2016 and June 10, 2017), T10(June 9, 2016 and May 31, 2017)) and 1 day before the second irrigation (E1(June 29, 2016 and June 20, 2017)) after seedling emergence, during 2016–2017. The control group (CK) had film mulching throughout the growth stages. Values are means ± standard deviation (n = 3)
From: Photosynthetic characteristics of cotton are enhanced by altering the timing of mulch film removal
Year | Varieties | Treatments | Days after flowering /d | ||||
|---|---|---|---|---|---|---|---|
5 | 15 | 25 | 35 | 45 | |||
2017 | XLZ42 | CK | 0.22 ± 0.01 | 0.28 ± 0.03 | 0.30 ± 0.01 | 0.27 ± 0.04 | 0.28 ± 0.02 |
|  |  | E1 | 0.27 ± 0.06 | 0.30 ± 0.01 | 0.29 ± 0.01 | 0.29 ± 0.03 | 0.28 ± 0.00 |
|  |  | T1 | 0.25 ± 0.04 | 0.29 ± 0.02 | 0.23 ± 0.02 | 0.31 ± 0.02 | 0.28 ± 0.01 |
|  |  | T10 | 0.28 ± 0.01 | 0.29 ± 0.01 | 0.28 ± 0.01 | 0.32 ± 0.03 | 0.32 ± 0.02 |
|  | XLZ45 | CK | 0.21 ± 0.03 | 0.25 ± 0.04 | 0.29 ± 0.01 | 0.29 ± 0.03 | 0.31 ± 0.03 |
|  |  | E1 | 0.19 ± 0.01 | 0.30 ± 0.00 | 0.25 ± 0.03 | 0.26 ± 0.02 | 0.27 ± 0.03 |
|  |  | T1 | 0.12 ± 0.07 | 0.32 ± 0.00 | 0.24 ± 0.06 | 0.30 ± 0.04 | 0.27 ± 0.06 |
|  |  | T10 | 0.29 ± 0.02 | 0.25 ± 0.01 | 0.26 ± 0.02 | 0.31 ± 0.02 | 0.33 ± 0.00 |
2016 | XLZ42 | CK | 0.23 ± 0.04 | 0.25 ± 0.02 | 0.29 ± 0.01 | 0.26 ± 0.02 | 0.29 ± 0.02 |
|  |  | E1 | 0.26 ± 0.02 | 0.25 ± 0.01 | 0.24 ± 0.01 | 0.23 ± 0.01 | 0.27 ± 0.05 |
|  |  | T1 | 0.23 ± 0.03 | 0.29 ± 0.05 | 0.28 ± 0.02 | 0.24 ± 0.02 | 0.27 ± 0.01 |
|  |  | T10 | 0.26 ± 0.00 | 0.28 ± 0.01 | 0.28 ± 0.02 | 0.26 ± 0.01 | 0.29 ± 0.00 |
|  | XLZ45 | CK | 0.26 ± 0.02 | 0.26 ± 0.01 | 0.27 ± 0.01 | 0.27 ± 0.02 | 0.29 ± 0.00 |
|  |  | E1 | 0.30 ± 0.02 | 0.26 ± 0.01 | 0.24 ± 0.01 | 0.27 ± 0.00 | 0.27 ± 0.00 |
|  |  | T1 | 0.27 ± 0.07 | 0.28 ± 0.01 | 0.27 ± 0.01 | 0.27 ± 0.01 | 0.29 ± 0.04 |
|  |  | T10 | 0.28 ± 0.01 | 0.27 ± 0.02 | 0.26 ± 0.01 | 0.27 ± 0.01 | 0.30 ± 0.01 |