Pumpkin is of great economic importance not only as food resources but also as the most widely used rootstock to graft cucurbit crops.Pumpkin rootstock improves salt tolerance of cucumber scion through respiratory bur...Pumpkin is of great economic importance not only as food resources but also as the most widely used rootstock to graft cucurbit crops.Pumpkin rootstock improves salt tolerance of cucumber scion through respiratory burst oxidase homolog protein D(CmRbohD)-mediated reactive oxygen species(ROS)burst,which further enhances Na^(+)export and K^(+)uptake.Rboh D activation requires calcium signaling.However,the underlying mechanism remains largely unknown.In this study,we discovered two Rboh D members from pumpkin involved in the ROS burst at the early stage of salt stress.CmRbohD1 and CmRbohD2 were functionally redundant and double mutation significantly impaired salt tolerance in pumpkin.Overexpression of CmRbohD1 and CmRbohD2 mitigated salinity-induced damage and maintained a relatively low Na+content and high K+content.We screened the potential calcineurin B-like interacting protein kinases(Cm CIPKs)which could bind with CmRbohD1 and CmRbohD2.Our results revealed that two Rboh Ds formed complexes specifically with CmCIPK1,thereby bursting ROS production.Overexpression of CmCIPK1 promoted the early ROS burst under salt stress condition and maintained a relatively balanced Na+/K+homeostasis.Altogether,we proposed a CmCIPK1-CmRbohD1/D2 complex for pumpkin salt stress signaling transduction,which regulates the ROS burst and Na+/K+homeostasis.Our findings offer unprecedented insights into the general mechanism of pumpkin salt tolerance.展开更多
Tomato(Solanum lycopersicum)is among the most important vegetables across the world,but cold stress usually affects its yield and quality.The wild tomato species Solanum habrochaites is commonly utilized as rootstock ...Tomato(Solanum lycopersicum)is among the most important vegetables across the world,but cold stress usually affects its yield and quality.The wild tomato species Solanum habrochaites is commonly utilized as rootstock for enhancing resistance against abiotic stresses in cultivated tomato,especially cold resistance.However,the underlying molecular mechanism remains unclear.In this research,we confirmed that S.habrochaites rootstock can improve the cold tolerance of cultivated tomato scions,as revealed by growth,physiological,and biochemical indicators.Furthermore,transcriptome profiling indicated significant differences in the scion of homo-and heterografted seedlings,including substantial changes in jasmonic acid(JA)biosynthesis and signaling,which were validated by RT–qPCR analysis.S.habrochaites plants had a high basal level of jasmonate,and cold stress caused a greater amount of active JA-isoleucine in S.habrochaites heterografts.Moreover,exogenous JA enhanced while JA inhibitor decreased the cold tolerance of tomato grafts.The JA biosynthesis-defective mutant spr8 also showed increased sensitivity to cold stress.All of these results demonstrated the significance of JA in the cold tolerance of grafted tomato seedlings with S.habrochaites rootstock,suggesting a future direction for the characterization of the natural variation involved in S.habrochaites rootstock-mediated cold tolerance.展开更多
The NAC transcription factor is a type of plant-specific transcription factor that can regulate plant salt tolerance,but the underlying mechanism is unclear in grafted vegetables.H2O2 and ABA in pumpkin rootstocks can...The NAC transcription factor is a type of plant-specific transcription factor that can regulate plant salt tolerance,but the underlying mechanism is unclear in grafted vegetables.H2O2 and ABA in pumpkin rootstocks can be transported to cucumber scion leaves,promoting stomatal closure to improve salt tolerance of grafted cucumbers.Despite these observations,the regulatory mechanism is unknown.Here,our research revealed that CmoNAC1 is a key transcription factor that regulates H_(2)O_(2) and ABA signaling in pumpkin roots under salt stress.The function of CmoNAC1 was analyzed using root transformation and RNA-seq,and we found that pumpkin CmoNAC1 promoted the production of H_(2)O_(2) and ABA via CmoRBOHD1 and CmoNCED6,respectively,and regulated K^(+)/Na^(+) homeostasis via CmoAKT1;2,CmoHKT1;1,and CmoSOS1 to improve salt tolerance of grafted cucumbers.Root knockout of CmoNAC1 resulted in a significant decrease in H_(2)O_(2)(52.9%and 32.1%)and ABA(21.8%and 42.7%)content and K^(+)/Na^(+) ratio(81.5%and 56.3%)in leaf and roots of grafted cucumber,respectively,while overexpression showed the opposite effect.The root transformation experiment showed that CmoNCED6 could improve salt tolerance of grafted cucumbers by regulating ABA production and K^(+)/Na^(+) homeostasis under salt stress.Finally,we found that CmoNAC1 bound to the promoters of CmoRBOHD1,CmoNCED6,CmoAKT1;2,and CmoHKT1;1 using yeast one-hybrid,luciferase,and electrophoretic mobility shift assays.In conclusion,pumpkin CmoNAC1 not only binds to the promoters of CmoRBOHD1 and CmoNCED6 to regulate the production of H_(2)O_(2) and ABA signals in roots,but also binds to the promoters of CmoAKT1;2 and CmoHKT1;1 to increase the K^(+)/Na^(+) ratio,thus improving salt tolerance of grafted cucumbers.展开更多
Soil salinity is a serious threat to horticultural production.Improving salt tolerance of vegetables by breeding is a difficult task as salt tolerance is a quantitative trait,regulated by a large number of genes.As a ...Soil salinity is a serious threat to horticultural production.Improving salt tolerance of vegetables by breeding is a difficult task as salt tolerance is a quantitative trait,regulated by a large number of genes.As a traditional agronomic method,grafting,which is widely practiced in vegetables,especially among members of Cucurbitaceae and Solanaceae,is a useful tool for reducing yield loss caused by salinity.However,the underlying mechanisms of this phenomenon remain largely unknown.Numerous studies have been conducted to uncover these mechanisms by which grafting improves salt tolerance in vegetables.This review summarizes the studies that have been conducted on this topic.In this review,the effects of salt stress on vegetable crops were discussed,and the four main mechanisms by which grafting increases the salt resistance of vegetables,namely,restricting the transport of toxic ions,enhancing the antioxidant system,enhancing the stability of the photosynthetic system,and sending root signals,were discussed.This review concludes by identifying several prospects for future research on increasing the adoption of grafting in vegetables under salinity stress.展开更多
基金supported by National Natural Science Foundation of China(Grant Nos.32072653,32372794,31772357)Natural Science Foundation of Hubei Province(Grant No.2019CFA017)+1 种基金Ningbo Scientific and Technological Project(Grant No.2021Z006)the Fundamental Research Funds for the Central Universities(Grant No.2662023YLPY008)。
文摘Pumpkin is of great economic importance not only as food resources but also as the most widely used rootstock to graft cucurbit crops.Pumpkin rootstock improves salt tolerance of cucumber scion through respiratory burst oxidase homolog protein D(CmRbohD)-mediated reactive oxygen species(ROS)burst,which further enhances Na^(+)export and K^(+)uptake.Rboh D activation requires calcium signaling.However,the underlying mechanism remains largely unknown.In this study,we discovered two Rboh D members from pumpkin involved in the ROS burst at the early stage of salt stress.CmRbohD1 and CmRbohD2 were functionally redundant and double mutation significantly impaired salt tolerance in pumpkin.Overexpression of CmRbohD1 and CmRbohD2 mitigated salinity-induced damage and maintained a relatively low Na+content and high K+content.We screened the potential calcineurin B-like interacting protein kinases(Cm CIPKs)which could bind with CmRbohD1 and CmRbohD2.Our results revealed that two Rboh Ds formed complexes specifically with CmCIPK1,thereby bursting ROS production.Overexpression of CmCIPK1 promoted the early ROS burst under salt stress condition and maintained a relatively balanced Na+/K+homeostasis.Altogether,we proposed a CmCIPK1-CmRbohD1/D2 complex for pumpkin salt stress signaling transduction,which regulates the ROS burst and Na+/K+homeostasis.Our findings offer unprecedented insights into the general mechanism of pumpkin salt tolerance.
基金This research was supported by the National Key Research and Development Program(2019YFD1001900,2022YFE0100900)the Natural Science Foundation of Hubei Province(2019CFA017).
文摘Tomato(Solanum lycopersicum)is among the most important vegetables across the world,but cold stress usually affects its yield and quality.The wild tomato species Solanum habrochaites is commonly utilized as rootstock for enhancing resistance against abiotic stresses in cultivated tomato,especially cold resistance.However,the underlying molecular mechanism remains unclear.In this research,we confirmed that S.habrochaites rootstock can improve the cold tolerance of cultivated tomato scions,as revealed by growth,physiological,and biochemical indicators.Furthermore,transcriptome profiling indicated significant differences in the scion of homo-and heterografted seedlings,including substantial changes in jasmonic acid(JA)biosynthesis and signaling,which were validated by RT–qPCR analysis.S.habrochaites plants had a high basal level of jasmonate,and cold stress caused a greater amount of active JA-isoleucine in S.habrochaites heterografts.Moreover,exogenous JA enhanced while JA inhibitor decreased the cold tolerance of tomato grafts.The JA biosynthesis-defective mutant spr8 also showed increased sensitivity to cold stress.All of these results demonstrated the significance of JA in the cold tolerance of grafted tomato seedlings with S.habrochaites rootstock,suggesting a future direction for the characterization of the natural variation involved in S.habrochaites rootstock-mediated cold tolerance.
基金supported by grants from the National Natural Science Foundation of China(31772357,32072653)the Natural Science Foundation of Hubei Province(2019CFA017)+1 种基金the Fundamental Research Funds for the Central Universities(2662023YLPY008)the Ningbo Scientific and Technological Project(2021Z006).
文摘The NAC transcription factor is a type of plant-specific transcription factor that can regulate plant salt tolerance,but the underlying mechanism is unclear in grafted vegetables.H2O2 and ABA in pumpkin rootstocks can be transported to cucumber scion leaves,promoting stomatal closure to improve salt tolerance of grafted cucumbers.Despite these observations,the regulatory mechanism is unknown.Here,our research revealed that CmoNAC1 is a key transcription factor that regulates H_(2)O_(2) and ABA signaling in pumpkin roots under salt stress.The function of CmoNAC1 was analyzed using root transformation and RNA-seq,and we found that pumpkin CmoNAC1 promoted the production of H_(2)O_(2) and ABA via CmoRBOHD1 and CmoNCED6,respectively,and regulated K^(+)/Na^(+) homeostasis via CmoAKT1;2,CmoHKT1;1,and CmoSOS1 to improve salt tolerance of grafted cucumbers.Root knockout of CmoNAC1 resulted in a significant decrease in H_(2)O_(2)(52.9%and 32.1%)and ABA(21.8%and 42.7%)content and K^(+)/Na^(+) ratio(81.5%and 56.3%)in leaf and roots of grafted cucumber,respectively,while overexpression showed the opposite effect.The root transformation experiment showed that CmoNCED6 could improve salt tolerance of grafted cucumbers by regulating ABA production and K^(+)/Na^(+) homeostasis under salt stress.Finally,we found that CmoNAC1 bound to the promoters of CmoRBOHD1,CmoNCED6,CmoAKT1;2,and CmoHKT1;1 using yeast one-hybrid,luciferase,and electrophoretic mobility shift assays.In conclusion,pumpkin CmoNAC1 not only binds to the promoters of CmoRBOHD1 and CmoNCED6 to regulate the production of H_(2)O_(2) and ABA signals in roots,but also binds to the promoters of CmoAKT1;2 and CmoHKT1;1 to increase the K^(+)/Na^(+) ratio,thus improving salt tolerance of grafted cucumbers.
基金supported by the National Natural Science Foundation of China (31772357,32072653,32002112)the Natural Science Foundation of Hubei Province (2019CFA017).
文摘Soil salinity is a serious threat to horticultural production.Improving salt tolerance of vegetables by breeding is a difficult task as salt tolerance is a quantitative trait,regulated by a large number of genes.As a traditional agronomic method,grafting,which is widely practiced in vegetables,especially among members of Cucurbitaceae and Solanaceae,is a useful tool for reducing yield loss caused by salinity.However,the underlying mechanisms of this phenomenon remain largely unknown.Numerous studies have been conducted to uncover these mechanisms by which grafting improves salt tolerance in vegetables.This review summarizes the studies that have been conducted on this topic.In this review,the effects of salt stress on vegetable crops were discussed,and the four main mechanisms by which grafting increases the salt resistance of vegetables,namely,restricting the transport of toxic ions,enhancing the antioxidant system,enhancing the stability of the photosynthetic system,and sending root signals,were discussed.This review concludes by identifying several prospects for future research on increasing the adoption of grafting in vegetables under salinity stress.
