Table 3.
Significance of relationships between plant growth (shoot and root RGR) among treatments across accessions and traits measured, for 15 accessions of Melilotus siculus under control (aerated root zone), stagnant (deoxygenated stagnant root zone), partial submergence or full shoot submergence (the latter two also with stagnant root zone)
| Assessed relationship | Pearson correlation coefficient | P-value | + or – trend | Source |
|---|---|---|---|---|
| Is growth under full submergence correlated with growth under the other treatments/growing conditions? | ||||
| Shoot RGR full submergence vs. shoot RGR control | 0.1 | 0.67 | n.s. | Supplementary Data Fig. S4 |
| Root RGR full submergence vs. root RGR control | 0.1 | 0.85 | n.s. | |
| Shoot RGR full submergence vs. shoot RGR stagnant | 0.47 | 0.06 | n.s. | |
| Root RGR full submergence vs. root RGR stagnant | 0.37 | 0.16 | n.s. | |
| Shoot RGR full submergence vs. shoot RGR partial submergence | 0.80 | <0.001 | + | |
| Root RGR full submergence vs. root RGR partial submergence | 0.81 | <0.001 | + | |
| Is the growth under full submergence conditions correlated with the initial leaf gas film thickness? | ||||
| Shoot RGR full submergence vs. leaflet gas film thickness | 0.57 | 0.026 | + | Supplementary Data Fig. S5 |
| Root RGR full submergence vs. leaflet gas film thickness | 0.51 | 0.06 | n.s. | |
| Is the shoot growth under partial submergence correlated with the amount of gas spaces (i.e. porosity) of petioles? | ||||
| Shoot RGR partial submergence vs. constitutive gas spaces in petioles | 0.61 | 0.015 | + | Supplementary Data Fig. S6 |
| Shoot RGR partial submergence vs. flood-induced gas spaces in petioles | 0.95 | <0.0001 | + | |
| Shoot RGR control vs. constitutive gas spaces in petioles | 0.30 | 0.27 | n.s. | |
| Shoot RGR control vs. flood-induced gas spaces in petioles | 0.37 | 0.17 | n.s. | |
| Is the recovery growth correlated with the growth during full submergence? | ||||
| Shoot RGR recovery vs. shoot RGR full submergence | 0.13 | 0.63 | n.s. | Supplementary Data Fig. S8 |
| Root RGR recovery vs. root RGR full submergence | 0.14 | 0.64 | n.s. | |
| Is the recovery growth correlated with the potential growth of accessions under control conditions? | ||||
| Shoot RGR recovery vs. shoot RGR control | 0.22 | 0.44 | n.s. | Supplementary Data Fig. S8 |
| Root RGR recovery vs. root RGR control | 0.31 | 0.26 | n.s. | |
| Is the recovery growth correlated with the number of green leaves maintained after full submergence? | ||||
| Shoot RGR recovery vs. number of green leaves | 0.89 | <0.0001 | + | Supplementary Data Fig. S9 |
| Root RGR recovery vs. number of green leaves | 0.77 | <0.001 | + | |
| Is the recovery growth correlated with the soluble sugars in leaves at the time of desubmergence? | ||||
| Shoot RGR recovery vs. soluble sugars in leaflets | 0.18 | 0.50 | n.s. | Supplementary Data Fig. S10 |
| Root RGR recovery vs. soluble sugars in leaflets | 0.15 | 0.58 | n.s. | |
| Is the recovery growth correlated with the initial leaf gas film thickness? | ||||
| Shoot RGR recovery vs. leaflet gas film thickness | 0.17 | 0.54 | n.s. | Supplementary Data Fig. S11 |
| Root RGR recovery vs. leaflet gas film thickness | 0.33 | 0.22 | n.s. | |
| Is the recovery growth correlated with the amount of gas spaces (i.e. porosity) of petioles? | ||||
| Shoot RGR recovery vs. constitutive gas spaces in petioles | 0.19 | 0.48 | n.s. | Supplementary Data Fig. S11 |
| Root RGR recovery vs. constitutive gas spaces in petioles | 0.14 | 0.61 | n.s. | |
| Is the recovery growth correlated with the developed phellem area? | ||||
| Shoot RGR recovery vs. phellem area full submergence | 0.02 | 0.94 | n.s. | Supplementary Data Fig. S11 |
| Root RGR recovery vs. phellem area full submergence | 0.09 | 0.74 | n.s. | |
Plants were 28 d old and exposed to treatments for an additional 7 d (and then the 35-day-old plants were measured or a set was desubmerged and measured after yet another 7 d).