Table 2.
Effect of soil drought on wheat genotypes differing in their drought susceptibility index (DSI) during the root-box experiment. Length of one seminal root (R1SL); total length of two seminal adventitious roots (R2SAL); number of nodal roots (RNo); length of nodal roots (RL); mean root length (RML); 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 | Seminal Roots | Seminal Adventitious Roots | Nodal Roots | ||
|---|---|---|---|---|---|---|
| R1SL (cm) | R2SAL (cm) | RNo | RL (cm) | RML (cm) | ||
| Drought-Sensitive Genotypes (DSI > 1.0) | ||||||
| Telimena | C | 43.2 a | 43.2 c | 16.7 a | 243.7 d | 14.6 d |
| D | 40.2 a | 49.8 a | 16.0 ab | 223.3 e | 14.0 d | |
| RTC | 0.07 | −0.15 | 0.04 | 0.08 | 0.04 | |
| Sirocco | C | 44.3 a | 41.8 d | 16.7 a | 262.2 c | 16.0 c |
| D | 42.0 a | 45.7 b | 15.7 ab | 230.7 de | 14.7 d | |
| RTC | 0.05 | −0.09 | 0.06 | 0.12 | 0.08 | |
| Goplana | C | 41.7 a | 50.7 a | 16.3 a | 279.8 a | 17.3 b |
| D | 41.6 a | 43.5 c | 15.3 b | 236.0 d | 15.4 cd | |
| RTC | 0.00 | 0.14 | 0.06 | 0.16 | 0.11 | |
| Mean ± SE | C | 42.2 ± 0.7 | 42.4 ± 1.4 | 16.6 ± 0.1 | 261.9 ± 10.4 | 16.1 ± 0.7 |
| D | 41.1 ± 0.8 | 39.4 ± 1.7 | 15.7 ± 0.2 | 230.0 ± 3.7 | 14.7 ± 0.4 | |
| RTC | 0.03 | 0.07 | 0.05 | 0.12 | 0.09 | |
| Drought-Resistant Genotypes (DSI < 1.0) | ||||||
| Sharki | C | 42.3 a | 44.3 bc | 15.3 b | 265.2 c | 17.3 b |
| D | 41.0 a | 38.5 f | 15.0 b | 257.3 c | 17.2 b | |
| RTC | 0.03 | 0.13 | 0.02 | 0.03 | 0.01 | |
| Struna | C | 43.0 a | 37.8 f | 16.0 a | 297.7 a | 18.6 a |
| D | 42.7 a | 46.7 b | 15.3 b | 283.3 b | 18.4 ab | |
| RTC | 0.01 | −0.23 | 0.04 | 0.05 | 0.01 | |
| SMJ 2115 | C | 41.0 a | 32.3 g | 16.0 a | 283.5 b | 17.7 ab |
| D | 43.3 a | 40.5 ef | 16.0 a | 275.0 bc | 17.2 b | |
| RTC | −0.06 | −0.25 | 0.00 | 0.03 | 0.03 | |
| Mean ± SE | C | 42.6 ± 0.5 | 40.0 ± 2.2 | 15.8 ± 0.2 | 282.1 ± 9.4 | 17.9 ± 0.4 |
| D | 41.9 ± 0.6 | 38.6 ± 1.9 | 15.4 ± 0.3 | 271.8 ± 7.6 | 17.7 ± 0.4 | |
| RTC | 0.02 | 0.04 | 0.03 | 0.04 | 0.01 | |
| ANOVA | ||||||
| Variable | df | R1SL | R2SAL | RNo | RL | RML |
| Genotype (G) | 5 | ns | * | ns | * | ns |
| Treatment (T) | 1 | ns | ns | ns | * | * |
| G × T | 5 | ns | ns | ns | ns | * |
Different letters indicate significant differences within columns, according to the Duncan’s test (p < 0.05); *—statistical significance at p < 0.1; 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.