Genotypic Variation in Nutrient Selectivity in Populus under NaCl Stress

编号 zgly0000303645

文献类型 期刊论文

文献题名 Genotypic Variation in Nutrient Selectivity in Populus under NaCl Stress

学科分类 220.99;林学其他学科

作者 ChenShaoliang  BaiGenben  LiuXiangfen  LiJinke  WangShasheng  AndreaPolle 

作者单位 CollegeofBiologicalSciencesandBiotechnology 

母体文献 Forestry Studies in China;中国林学: 英文版 

年卷期 2003,5(1)

页码 1-7

年份 2003 

分类号 S792.11 

关键词 杨树  盐胁迫  遗传变异  耐盐性  木质部  营养物质  选择性吸收 

文摘内容 We used a salt-resistant poplar genotype Populus euphratlca and two salt-sensitive genotypes.Populus ‘popularis 35-44'(P.popularis)and the hybrid P.talassica Kom ×(P.euphratica+Salix alba L.)to examine genotypic differences in nutrient selectivity under NaCl stress.One-year-old seedlings of P.euphratica and one-year-old hardwood cuttings of P.Popularis were used in a short-term study (24 hours),while in a long-term study ,up to 4 weeks,two-year-old seedlings of P.euphratica and the hybridP.talassica Kom×(P.euphrattica+Salix alba L.)were compared.In the short-term study ,K^+ concentration in the xylem sap([K^+]xylem) of P.euphratica significantly increased after salt stress was initiated,and maintained 1-2 fold higher than control levels during the period of salt stress(24 hours) .Xylem Ca^2+ and Mg^2+ concentrations([Ca^2+]xylem)in P.euphratica resembled the pattern of K^+ despite a lesser magnitude in elevation.However,[K^+]xylem,[Ca^2+]xylem and [Mg^2+]xylem in P.Popularis exhibited a transient increase at the beginning of salt treatment,thereafter,they all returned to control levels at 4 hours and no further rise was observed in the following hours.Xylem Na^+/K^+,Na^+/Ca^2+ and Na^+/Mg^2+ in P.popularis increased sharply upon NaCl stress and steadily reached the maximum at 24 hours.In contrast,xylem Na^+/K^+,Na^+/Ca^+ and Na^+/Mg^2+ in NaCl-treated plants of P.euphratica did not significantly increase during the period of salt stress (24 hours).Noteworthy.Na^+/K^+ markedly declined after the onset of stress.These results suggest that P.euphratica had a higher nutrient selectivity in face of salinity.A same trend was observed in a 4-week study Xylem Na^+/K^+,Na^+/Ca^2+ and Na^+/Mg^2+ in salinised plants of the hybrid abruptly increased after 4 days of stress,and then continuously increased to reach the highest level at day 8 or day 15.In comparison,the magnitude of Na^+/K^+,Na^+/Ca^2+ and Na^+/Mg^2+ elevation in the xylem of P.euphratica was much lower during the observation period.In conclusion,salt-tolerant genotype P.euphratica maintained a higher nutrient selectivity under saline stress,as compared to the two salt-sensitive genotypes.The high capacity for nutrient uptake and transport presumably contributes to the salt tolerance of P.euphratica in a longer term。