在温室条件下,采用盆栽根箱培养的方法研究盐胁迫下I 69杨(Populus deltoides Bartr.cv.’Lux’) 和NL 1381杨〔Populus deltoides Bartr.cv.’Lux’ ×P. euramericana (Dode) Geninier CL’I 45 51’〕根际、非根际土壤盐分分布特征。盐处理浓度共设3个水平:CK(NaCl0g /kg)、处理A(NaCl1g/ kg)和处理B(NaCl2g/kg),采用完全随机设计。结果表明,2个杨树无性系根际水溶性K+亏缺,水溶性Na⁺、Ca²⁺和Mg²⁺富集。K⁺的亏缺率及Na⁺的富集率随NaCl处理浓度的增大而减小,Ca²⁺和Mg²⁺的富集率在非盐渍条件下最低,处理A达最高,处理B较处理A略有下降。在盐胁迫下,无性系NL 1381杨根际土壤Na⁺的浓度和电导率均低于无性系I 69杨,可以有效减轻盐分对根系的渗透胁迫,相对而言具有较强的抗盐性。

The rhizobox experiments were randomized completely designed, with application of NaCl to furnish 0, 1 and 2 g/kg soil, to study the distribution of K ⁺ , Na ⁺ , Ca²⁺ and Mg²⁺ in poplar rhizosphere system under NaCl stress in greenhouse. Two poplar clones, I-69 ( Populus deltoides Bartr. cv. `Lux') andNL-1381 〔Populus deltoides Bartr. cv. `Lux' ×P . euramericana ( Dode) Geninier CL `I-45 51'〕, were chosen for the study. The results indicated that the water-soluble K⁺ of soils in rhizosphere of two poplar clones was lower than those in non-rhizosphere, but Na⁺, Ca²⁺ and Mg²⁺ were accumulated obviously in rhizosphere under three NaCl treatments. The depleting ratio of K ⁺ and accumulating ratio of Na + for each system of clones decreased with the increase of NaCl concentration, but the accumulating ratios of Ca²⁺ and Mg²⁺ under treatment B (NaCl 2 g/kg) were obviously higher than under control, but slightly lower than those of treatment A ( NaCl 1 g/kg) . Na⁺ concentration and electrical conductivity in rhizosphere of clone NL-1381were lower in comparison with clone I-69 under NaCl treatments, and therefore reducing the salt stress. It is probably that clone NL-1381 is stronger in tolerating salt stress.