Table 1.
Effect of soil drought on wheat genotypes differing in their drought susceptibility index (DSI) during the root-box experiment. Plant height (H); leaf number (LNo); dry matter of shoot (S); dry matter of roots growing in two soil levels (RU, upper from 0 to 15 cm; RB, bottom from 15 to 40 cm); total root dry matter (R); total plant dry matter (S + R); shoot-to-root ratio (S/R); control treatment (C); drought treatment (D); relative trait change index (RTC); the mean of plant group is provided together with the standard error (SE); (n = 3).
| Genotype | Treatment | H (cm) | LNo | Dry Matter (g plant−1) | |||||
|---|---|---|---|---|---|---|---|---|---|
| S | RU | RB | R (RU + RB) | S + R | S/R | ||||
| Drought-Sensitive Genotypes (DSI > 1.0) | |||||||||
| Telimena | C | 51.30 b | 6.70 a | 1.48 a | 0.28 b | 0.55 a | 0.82 ab | 2.30 a | 1.80 a |
| D | 40.00 de | 6.30 ab | 0.95 d | 0.24 c | 0.32 e | 0.56 b | 1.51 c | 1.70 ab | |
| RTC | 0.22 | 0.06 | 0.36 | 0.14 | 0.42 | 0.32 | 0.34 | 0.06 | |
| Sirocco | C | 58.00 a | 6.30 ab | 1.44 ab | 0.28 b | 0.55 a | 0.83 a | 2.27 a | 1.74 a |
| D | 44.00 d | 6.00 b | 0.97 d | 0.24 c | 0.32 e | 0.56 b | 1.53 c | 1.73 a | |
| RTC | 0.24 | 0.05 | 0.33 | 0.14 | 0.42 | 0.32 | 0.33 | 0.01 | |
| Goplana | C | 51.70 b | 6.30 ab | 1.33 b | 0.25 bc | 0.51 ab | 0.84 a | 2.17 a | 1.59 cd |
| D | 41.00 de | 5.70 bc | 0.79 e | 0.23 c | 0.30 e | 0.53 d | 1.32 d | 1.49 d | |
| RTC | 0.21 | 0.10 | 0.41 | 0.08 | 0.41 | 0.37 | 0.39 | 0.06 | |
| Mean ± SE | C | 53.70 ± 2.17 | 6.40 ± 0.10 | 1.41 ± 0.05 | 0.27 ± 0.01 | 0.54 ± 0.01 | 0.83 ± 0.01 | 2.24 ± 0.04 | 1.71 ± 0.06 |
| D | 41.70 ± 1.20 | 6.00 ± 0.20 | 0.90 ± 0.05 | 0.24 ± 0.05 | 0.31 ± 0.01 | 0.55 ± 0.01 | 1.45 ± 0.07 | 1.64 ± 0.08 | |
| RTC | 0.22 | 0.07 | 0.36 | 0.11 | 0.43 | 0.34 | 0.35 | 0.04 | |
| Drought-Resistant Genotypes (DSI < 1.0) | |||||||||
| Sharki | C | 46.30 c | 6.00 b | 1.34 b | 0.28 b | 0.56 a | 0.82 a | 2.18 a | 1.59 cd |
| D | 38.00 de | 4.70 d | 1.10 cd | 0.34 a | 0.47 c | 0.81 ab | 1.91 b | 1.37 e | |
| RTC | 0.18 | 0.22 | 0.18 | −0.21 | 0.16 | 0.01 | 0.12 | 0.14 | |
| Struna | C | 47.30 c | 6.00 b | 1.37 b | 0.27 bc | 0.53 ab | 0.80 b | 2.17 a | 1.71 ab |
| D | 38.70 de | 4.70 d | 1.10 c | 0.32 a | 0.43 cd | 0.75 bc | 1.85 b | 1.49 d | |
| RTC | 0.18 | 0.22 | 0.20 | −0.18 | 0.19 | 0.06 | 0.15 | 0.13 | |
| SMJ 2115 | C | 49.70 bc | 6.30 ab | 1.33 b | 0.24 c | 0.54 ab | 0.81 ab | 2.14 ab | 1.65 bc |
| D | 41.30 de | 5.30 c | 0.99 d | 0.30 ab | 0.40 d | 0.73 c | 1.72 c | 1.36 e | |
| RTC | 0.17 | 0.16 | 0.26 | −0.25 | 0.25 | 0.10 | 0.20 | 0.18 | |
| Mean ± SE | C | 47.80 ± 1.00 | 6.10 ± 0.10 | 1.35 ± 0.01 | 0.27 ± 0.00 | 0.54 ± 0.01 | 0.82 ± 0.01 | 2.16 ± 0.01 | 1.65 ± 0.03 |
| D | 39.30 ± 1.00 | 4.90 ± 0.20 | 1.06 ± 0.04 | 0.32 ± 0.01 | 0.43 ± 0.02 | 0.76 ± 0.02 | 1.82 ± 0.06 | 1.40 ± 0.04 | |
| RTC | 0.18 | 0.20 | 0.21 | −0.19 | 0.20 | 0.07 | 0.16 | 0.15 | |
| ANOVA | |||||||||
| Variable | df | H | LNo | S | RU | RB | R | R + S | S/R |
| Genotype (G) | 5 | ** | ns | * | ** | ** | * | ** | *** |
| Treatment (T) | 1 | * | ns | * | * | * | * | * | * |
| G × T | 5 | * | ns | * | * | * | * | * | * |
Different letters indicate significant differences within columns, according to the Duncan’s test (p < 0.05); *, **, ***—statistical significance at p < 0.1, 0.05, 0.01, respectively; ns—no significant differences; df—number of freedom degree. Based on RTC, the genotypes were divided into three groups: yellow—statistically significant decrease of traits under D in comparison with C; green—statistically significant increase of trait under D in comparison with C; blue—no statistically significant differences between C and D.