Stomatal sensitivity to root signals induced by soil drying may vary between environments and plant species. This is likely to be a result of the interactions and modulations ámong root signals. As a stress signa...Stomatal sensitivity to root signals induced by soil drying may vary between environments and plant species. This is likely to be a result of the interactions and modulations ámong root signals. As a stress signal, abscisic acid （ABA） plays a central role in root to shoot signaling, pH and hydraulic signals may interact with ABA signals and thus, jointly regulate stomatal responses to changed soil water status, pH itself can be modified by several factors, among which the chemical compositions in the xylem stream and the live cells surrounding the vessels play crucial roles. In addition to the xylem pH, more attention should be paid to the direct modulation of leaf apoplastic pH, because many chemical compositions might strongly modify the leaf apoplastic pH while having no significant effect on the xylem pH. The direct modulation of the ABA signal intensity may be more important for the regulation of stomatal responses to soil drying than the ABA signal per se. The ABA signal is also regulated by the ABA catabolism and the supply of precursors to the roots if a sustained root to shoot communication of soil drying operates at the whole plant level. More importantly, ABA catabolism could play crucial roles in the determination of the fate of the ABA signal and thereby control the stomatal behavior of the root-sourced ABA signal.展开更多
Drought tolerance and toxicity variation of grass pea (Lathyrus Sativus L.) were studied in the presence and absence of earth element Eu 3+ under the pot-culture condition. The addition of exogenous Eu 3+ increases th...Drought tolerance and toxicity variation of grass pea (Lathyrus Sativus L.) were studied in the presence and absence of earth element Eu 3+ under the pot-culture condition. The addition of exogenous Eu 3+ increases the survival days (SD) and lowered the stomatal sensitivity of grass pea seedlings under the decreasing soil moisture from -0.2 MPa to -1 MPa, suggesting that Eu 3+ can improve the ability of grass pea seedlings to tolerate drought. But in this case, Eu 3+ is found to significantly inhibit the increase in contents of plant toxicity β-N-oxalyl-L-a, β-diaminopropionic acid (ODAP) level in leaves. Therefore, the results demonstrate that Eu 3+ application is a potential agronomic approach to improve drought tolerance while lowering the toxicity level in grass pea productivity.展开更多
文摘Stomatal sensitivity to root signals induced by soil drying may vary between environments and plant species. This is likely to be a result of the interactions and modulations ámong root signals. As a stress signal, abscisic acid （ABA） plays a central role in root to shoot signaling, pH and hydraulic signals may interact with ABA signals and thus, jointly regulate stomatal responses to changed soil water status, pH itself can be modified by several factors, among which the chemical compositions in the xylem stream and the live cells surrounding the vessels play crucial roles. In addition to the xylem pH, more attention should be paid to the direct modulation of leaf apoplastic pH, because many chemical compositions might strongly modify the leaf apoplastic pH while having no significant effect on the xylem pH. The direct modulation of the ABA signal intensity may be more important for the regulation of stomatal responses to soil drying than the ABA signal per se. The ABA signal is also regulated by the ABA catabolism and the supply of precursors to the roots if a sustained root to shoot communication of soil drying operates at the whole plant level. More importantly, ABA catabolism could play crucial roles in the determination of the fate of the ABA signal and thereby control the stomatal behavior of the root-sourced ABA signal.
文摘Drought tolerance and toxicity variation of grass pea (Lathyrus Sativus L.) were studied in the presence and absence of earth element Eu 3+ under the pot-culture condition. The addition of exogenous Eu 3+ increases the survival days (SD) and lowered the stomatal sensitivity of grass pea seedlings under the decreasing soil moisture from -0.2 MPa to -1 MPa, suggesting that Eu 3+ can improve the ability of grass pea seedlings to tolerate drought. But in this case, Eu 3+ is found to significantly inhibit the increase in contents of plant toxicity β-N-oxalyl-L-a, β-diaminopropionic acid (ODAP) level in leaves. Therefore, the results demonstrate that Eu 3+ application is a potential agronomic approach to improve drought tolerance while lowering the toxicity level in grass pea productivity.
