Responses of Sesbania rostrata and S. cannabina to Pb, Zn, Cu and Cd toxicities were assessed by a seed-suspending seedbed(SSS) approach. The results showed that the SSS approach was suitable for testing the tolerance...Responses of Sesbania rostrata and S. cannabina to Pb, Zn, Cu and Cd toxicities were assessed by a seed-suspending seedbed(SSS) approach. The results showed that the SSS approach was suitable for testing the tolerance of a plant to the stress of toxic metals. The endpoints include seed germination success, straightened radicle and hypocotyl of the seedlings from the seeds. The measurements could be done easily and accurately. It was found that the elongation of radicle was the most sensitive indicator to the stress of heavy metals among the endpoints. When exposure to lower or medium concentrations of Pb, Zn, and Cd, the development of the lateral roots were favorable. Species of S. rostrata was more tolerant than S. cannabina to the heavy metals, especially to Zn and Cd. The ED 50 of Pb, Zn, Cu and Cd were 32.90, 5.32, 4.40 and 12.00 μg/ml for S. rostrata, respectively, and they were 30.11, 2.87, 4.05 and 4.94 μg/ml respectively for S. cannabina.展开更多
Alkaline soils pose an increasing problem for agriculture worldwide,but using stress-tolerant plants as green manure can improve marginal land.Here,we show that the legume Sesbania cannabina is very tolerant to alkali...Alkaline soils pose an increasing problem for agriculture worldwide,but using stress-tolerant plants as green manure can improve marginal land.Here,we show that the legume Sesbania cannabina is very tolerant to alkaline conditions and,when used as a green manure,substantially improves alkaline soil.To understand genome evolution and the mechanisms of stress tolerance in this allotetraploid legume,we generated the first telomere-to-telomere genome assembly of S.cannabina spanning~2,087 Mb.The assembly included all centromeric regions,which contain centromeric satellite repeats,and complete chromosome ends with telomeric characteristics.Further genome analysis distinguished A and B subgenomes,which diverged approximately 7.9 million years ago.Comparative genomic analysis revealed that the chromosome homoeologs underwent large-scale inversion events(>10 Mb)and a significant,transposon-driven size expansion of the chromosome 5A homoeolog.We further identified four specific alkali-induced phosphate transporter genes in S.cannabina;these may function in alkali tolerance by relieving the deficiency in available phosphorus in alkaline soil.Our work highlights the significance of S.cannabina as a green tool to improve marginal lands and sheds light on subgenome evolution and adaptation to alkaline soils.展开更多
文摘Responses of Sesbania rostrata and S. cannabina to Pb, Zn, Cu and Cd toxicities were assessed by a seed-suspending seedbed(SSS) approach. The results showed that the SSS approach was suitable for testing the tolerance of a plant to the stress of toxic metals. The endpoints include seed germination success, straightened radicle and hypocotyl of the seedlings from the seeds. The measurements could be done easily and accurately. It was found that the elongation of radicle was the most sensitive indicator to the stress of heavy metals among the endpoints. When exposure to lower or medium concentrations of Pb, Zn, and Cd, the development of the lateral roots were favorable. Species of S. rostrata was more tolerant than S. cannabina to the heavy metals, especially to Zn and Cd. The ED 50 of Pb, Zn, Cu and Cd were 32.90, 5.32, 4.40 and 12.00 μg/ml for S. rostrata, respectively, and they were 30.11, 2.87, 4.05 and 4.94 μg/ml respectively for S. cannabina.
基金This work was supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA28030000)the National Key Research and Development Program of China(2022YFD1500503,2022YFF1003401)+2 种基金Science&Technology Specific Projects in Agricultural High-tech Industrial Demonstration Area of the Yellow River Delta(2022SZX14)the earmarked fund for CARS-Green Manure(CARS-22)the Youth Innovation Promotion Association of CAS(Y2022039).
文摘Alkaline soils pose an increasing problem for agriculture worldwide,but using stress-tolerant plants as green manure can improve marginal land.Here,we show that the legume Sesbania cannabina is very tolerant to alkaline conditions and,when used as a green manure,substantially improves alkaline soil.To understand genome evolution and the mechanisms of stress tolerance in this allotetraploid legume,we generated the first telomere-to-telomere genome assembly of S.cannabina spanning~2,087 Mb.The assembly included all centromeric regions,which contain centromeric satellite repeats,and complete chromosome ends with telomeric characteristics.Further genome analysis distinguished A and B subgenomes,which diverged approximately 7.9 million years ago.Comparative genomic analysis revealed that the chromosome homoeologs underwent large-scale inversion events(>10 Mb)and a significant,transposon-driven size expansion of the chromosome 5A homoeolog.We further identified four specific alkali-induced phosphate transporter genes in S.cannabina;these may function in alkali tolerance by relieving the deficiency in available phosphorus in alkaline soil.Our work highlights the significance of S.cannabina as a green tool to improve marginal lands and sheds light on subgenome evolution and adaptation to alkaline soils.