Exogenous jasmonic acid (JA) has been showed to be able to induce stomatal closure in Vicia faba L. in previous investigations. The transport and distribution of 3H-JA affected by localized scorch on V. faba seedl...Exogenous jasmonic acid (JA) has been showed to be able to induce stomatal closure in Vicia faba L. in previous investigations. The transport and distribution of 3H-JA affected by localized scorch on V. faba seedling were studied with radioisotope technique. The results showed that 3H-JA could be transported up or down at the rate of 4-5 cm·min -1 following feeding into root or shoot tip. The transport of 3H-JA in shoot reached a relative stable rate at 30 min after being fed through root. Wounding by scorch in the youngest leaf caused an increase in the transport of 3H-JA from root to shoot and enhanced the distribution of 3H-JA in the wounded leaf. However, distribution of 3H-JA in unwounded leaves increased after 5 h being fed through the youngest leaf. It was noticed that wounding improved accumulation of 3H-JA in abaxial epidermis. Consistent results were obtained: wounding prevented transport of 3H-JA out from the youngest leaf to root; These observations suggest that JA plays an important role as a defense signal and might be involved in the regulation of the stomatal movement in response to wounding stress.展开更多
Aims Drought and salinity are severe abiotic stress factors,which limit plant growth and productivity,particularly in desert regions.In this study,we employed two desert poplars,Populus euphratica Oliver and Populus p...Aims Drought and salinity are severe abiotic stress factors,which limit plant growth and productivity,particularly in desert regions.In this study,we employed two desert poplars,Populus euphratica Oliver and Populus pruinosa Schrenk seedlings,to compare their tolerance to drought,salinity and combined stress.Methods We investigated species-specific responses of P.euphratica and P.pruinosa in growth,photosynthetic capacity and pigment contents,nonstructural carbohydrate concentrations,Cl−allocation,osmotic regulation and the accumulation of reactive oxygen species(ROS)under drought,salinity and the combined stress.Important Findings Populus pruinosa exhibited greater growth inhibitory effects,photosynthesis decline,stomatal closure and ROS accumulation,and lower antioxidant enzyme activities and osmotic regulation compared with P.euphratica under drought,salinity and especially under their combined stress.On the other hand,salt-stressed P.euphratica plants restricted salt transportation from roots to leaves,and allocated more Cl−to coarse roots and less to leaves,whereas salt-stressed P.pruinosa allocated more Cl−to leaves.It was shown that there is species-specific variation in these two desert poplars,and P.pruinosa suffers greater negative effects compared with P.euphratica under drought,salinity and especially under the combined stress.Therefore,in ecological restoration and afforestation efforts,species-specific responses and tolerances of these two poplar species to drought and salinity should be considered under climate change with increasing drought and soil salinity developing.展开更多
文摘Exogenous jasmonic acid (JA) has been showed to be able to induce stomatal closure in Vicia faba L. in previous investigations. The transport and distribution of 3H-JA affected by localized scorch on V. faba seedling were studied with radioisotope technique. The results showed that 3H-JA could be transported up or down at the rate of 4-5 cm·min -1 following feeding into root or shoot tip. The transport of 3H-JA in shoot reached a relative stable rate at 30 min after being fed through root. Wounding by scorch in the youngest leaf caused an increase in the transport of 3H-JA from root to shoot and enhanced the distribution of 3H-JA in the wounded leaf. However, distribution of 3H-JA in unwounded leaves increased after 5 h being fed through the youngest leaf. It was noticed that wounding improved accumulation of 3H-JA in abaxial epidermis. Consistent results were obtained: wounding prevented transport of 3H-JA out from the youngest leaf to root; These observations suggest that JA plays an important role as a defense signal and might be involved in the regulation of the stomatal movement in response to wounding stress.
基金supported by the Natural Science Foundation of China(U1803231)and the Talent Program of the Hangzhou Normal University(2016QDL020).
文摘Aims Drought and salinity are severe abiotic stress factors,which limit plant growth and productivity,particularly in desert regions.In this study,we employed two desert poplars,Populus euphratica Oliver and Populus pruinosa Schrenk seedlings,to compare their tolerance to drought,salinity and combined stress.Methods We investigated species-specific responses of P.euphratica and P.pruinosa in growth,photosynthetic capacity and pigment contents,nonstructural carbohydrate concentrations,Cl−allocation,osmotic regulation and the accumulation of reactive oxygen species(ROS)under drought,salinity and the combined stress.Important Findings Populus pruinosa exhibited greater growth inhibitory effects,photosynthesis decline,stomatal closure and ROS accumulation,and lower antioxidant enzyme activities and osmotic regulation compared with P.euphratica under drought,salinity and especially under their combined stress.On the other hand,salt-stressed P.euphratica plants restricted salt transportation from roots to leaves,and allocated more Cl−to coarse roots and less to leaves,whereas salt-stressed P.pruinosa allocated more Cl−to leaves.It was shown that there is species-specific variation in these two desert poplars,and P.pruinosa suffers greater negative effects compared with P.euphratica under drought,salinity and especially under the combined stress.Therefore,in ecological restoration and afforestation efforts,species-specific responses and tolerances of these two poplar species to drought and salinity should be considered under climate change with increasing drought and soil salinity developing.
