Table 1.
Sirius cultivar parameters with the value ranges used in ideotype optimization, from Semenov et al. (2014)
(1) Using a model of canopy photosynthesis, it was shown that 10% in L could be achieved if λ (Rubisco specificity factor) was optimized (Zhu et al., 2010). (2) Genetic variations of Ph up to 20% were observed for wheat (Mossad et al., 1995; M. Ishag et al., 1998). (3) Varietal difference in number of days till heading under long and short day conditions varied between 9.74 and 107.40 in a photoperiodic response experiment (Košner and Žurková, 1996). (4) Genetic variation of Gf up to 40% was observed for wheat (Robert et al., 2001; Charmet et al., 2005; Akkaya et al., 2006). (5) The reported range of genetic variation for flag leaf area under unlimited water and nitrogen was up to 40% (Fischer et al., 1998; Shearman et al., 2005). (6) Large genotypic variation in root characteristics and water uptake was reported (Asseng et al., 1998; Manschadi et al., 2006).
| Parameter | Symbol | Range | |
|---|---|---|---|
| Photosynthesis | |||
| Light conversion efficiency | L | 1.10 (dimensionless) | (1) |
| Phenology | |||
| Phyllochron | Ph | 70–130 (°Cd) | (2) |
| Day length response | Pp | 0.05–0.70 (leaf h–1 day length) | (3) |
| Duration of grain filling | Gf | 500–900 (°Cd) | (4) |
| Canopy | |||
| Maximum area of flag leaf | A | 0.003–0.01 (m2 leaf m–2 soil) | (5) |
| ‘Stay green’ | S | 0–1.5 (dimensionless) | |
| Drought tolerance | |||
| Response of photosynthesis to water stress | Wsa | 0.1–0.21 (dimensionless) | |
| Maximum acceleration of leaf senescence caused by water deficiency | Wss | 1.2–1.9 (dimensionless) | |
| Root water uptake | |||
| Rate of water uptake | Ru | 1–7% | (6) |