Table 1.
Mean phenotypic performance of the Cocodrie x N22 RIL population for various morphological and physiological traits at the seedling stage, under non-stress or alkaline stress environments.
| Alkaline Stress | Control | Reduction in Trait Mean (%) Under Stress d | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Trait a | Cocodrie Mean | N22 Mean b | RIL Mean c | RIL Range |
h2 | Cocodrie Mean |
N22 Mean b | RIL Mean | RIL Range | Cocodrie | N22 |
| AKT | 4.3 | 9.0 ** | 5.0 ** | 2.0–9.0 | 0.7 | 1.0 | 1.0 ns | 1.1 | 1.0–3.0 | −76.7 | −88.9 |
| CHL (SPAD) | 18.4 | 2.7 * | 11.3 * | 2.2–22.1 | 0.5 | 29.9 | 27.2 ns | 25.5 | 18.2–34.2 | 38.5 | 90.1 |
| SHL (cm) | 22.2 | 18.5 * | 28.1 ** | 17.2–40.1 | 0.8 | 34.7 | 36.0 ns | 37.8 | 20.3–55.3 | 35.9 | 48.6 |
| RTL (cm) | 12.3 | 8.3 * | 10.4 ** | 3.9–14.1 | 0.7 | 14.7 | 15.7 ns | 12.7 | 5.5–16.5 | 16.1 | 47.0 |
| RSR | 0.6 | 0.4 ** | 0.4 ** | 0.2–0.8 | 0.7 | 0.4 | 0.5 ns | 0.4 | 0.2–0.6 | −35.7 | 2.2 |
| SNC (mmol/Kg) | 1448.2 | 2734.2 ** | 1690.4 ** | 832.4–2734.2 | 0.9 | 866.7 | 900.0 ns | 944.0 | 508.3–1383.3 | −67.1 | −203.8 |
| SKC (mmol/Kg) | 408.6 | 153.6 ** | 365.1 ** | 149.2–592.3 | 0.8 | 711.3 | 720.0 ns | 755.2 | 406.7–1106.7 | 42.6 | 78.7 |
| RNC (mmol/Kg) | 1619.2 | 2900.1 ** | 1851.7 ** | 903.3–2900.1 | 0.8 | 1106.0 | 657.1 ** | 1048.4 | 564.5–1536.3 | −46.4 | −341.3 |
| RKC (mmol/Kg) | 431.0 | 131.3 ** | 342.6 ** | 131.3–556.2 | 0.9 | 779.3 | 809.3 ns | 848.8 | 124.3–457.1 | 44.7 | 83.8 |
| SNK | 3.5 | 20.8 ** | 5.1 ** | 1.4–20.8 | 0.9 | 1.2 | 1.3 ns | 1.5 | 1.1–2.9 | −192.6 | −1565.6 |
| RNK | 3.8 | 23.0 ** | 6.0 ** | 1.6–23.0 | 0.9 | 1.4 | 0.8 ns | 1.4 | 0.6–3.1 | −166.0 | −2739.5 |
a AKT, alkalinity tolerance scoring; CHL, chlorophyll content; SHL, shoot length; RTL, root length; RSR, root-to-shoot ratio; SNC, shoot Na+ concentration; SKC, shoot K+ concentration; RNC, root Na+ concentration; RKC, root K+ concentration; SNK, shoot Na+: K+ ratio; RNK, root Na+: K+ ratio. b t-test between Cocodrie and N22; c genotypic difference among RILs; d negative and positive values indicate increase and decrease in trait mean, respectively. *, ** significant differences between the means for Cocodrie and N22 at 0.05 and 0.01 level of probability, respectively. ns nonsignificant. h2—heritability.