Table 5.
The effect of reduced kernel number* on the response of kernel filling in wheat to drought and high temperature following anthesis
| Treatment | Mean days after anthesis | Flag blade Ψw (MPa)* | NCE (µmol m–2 s–1)† | Kernel dry weight at maturity(mg)‡ |
| 18/13 °C | ||||
| Control | ||||
| Full kernel number | 20·0 | –0·73 ± 0·08 (7) | 14·9 ± 0·7 (8) | 74·9 ± 0·8 (33) |
| Reduced kernel number | 20·0 | –0·59 ± 0·16 (5) | 15·4 ± 0·7 (6) | 77·6 ± 0·7 (31) |
| Droughted | ||||
| Full kernel number | 19·4 | –1·79 ± 0·24 (9) | 3·0 ± 1·3 (17) | 27·1 ± 1·2 (33) |
| Reduced kernel number | 19·0 | –1·89 ± 0·11 (9) | 3·5 ± 0·9 (17) | 36·2 ± 1·6 (29) |
| 27/22 °C | ||||
| Control | ||||
| Full kernel number | 13·9 | –0·76 ± 0·05 (6) | 14·6 ± 2·0 (6) | 51·0 ± 0·5 (36) |
| Reduced kernel number | 13·6 | –0·75 ± 0·12 (6) | 14·2 ± 1·2 (7) | 51·6 ± 1·7 (35) |
| Droughted | ||||
| Full kernel number | 13·6 | –3·70 ± 0·25 (10) | 1·0 ± 0·3 (10) | 30·5 ± 0·7 (34) |
| Reduced kernel number | 13·1 | –1·79 ± 0·18 (12) | 4·7 ± 0·6 (12) | 42·1 ± 0·7 (34) |
Each value is the mean ± s.e. of the number of replicates shown in parentheses.
* Mean kernel number per ear reduced from 40·1 to 17·2 by removing the kernels from all but the five central spikelets.
† Flag leaf Ψw and NCE measured 19–20 d after anthesis in plants held at 18/13 °C from anthesis and 13–14 d after anthesis in plants held at 27/22 °C from anthesis.
‡ Data relating to floret ‘b’ kernels.