Abstract: In order to understand the salt-tolerant characteristics of Sorbus sibirica ‘DongHong’,the seedlings of S. sibirica ‘DongHong’ were used as materials,and the effects of NaCl,NaHCO₃ and mixed salt on the growth,physiology and photosynthesis of the seedlings were studied. The results showed that the root length,root surface area,root volume,root mean diameter and root tip number of S. sibirica ‘DongHong’ were inhibited at different degrees with the increase of salt concentration,and the inhibition degree of neutral salt was the least. At 200 mmol·L^-1 of basic salt,the inhibition reached the maximum,and the root-shoot ratio and root biomass decreased,while the reduction of neutral salt was small. The contents of malondialdehyde and proline increased,while the activities of superoxide dismulase and peroxidase increased first and then decreased. The Intercellular CO₂ concentration showed an upward trend,while the net photosynthetic rate，stomatal conductance and transpiration rate all showed a downward trend. The biomass,total root length,root surface area,root volume,root tip number,net photosynthetic rate,transpiration rate and stomatal conductance were screened out by principal component analysis.

Key words: Sorbus sibirica ‘DongHong’, Salt alkali stress, Growth characteristics, Physiological characteristics, Photosynthetic characteristics

摘要： 为探究‘冬红’花楸（Sorbus sibirica ‘DongHong’）的耐盐特性，本试验以‘冬红’花楸幼苗为材料，采用中性盐NaCl、碱性盐NaHCO₃、混合盐对‘冬红’花楸幼苗胁迫处理，分析不同浓度盐碱胁迫对‘冬红’花楸生长、生理及光合指标的影响。结果表明：随着盐浓度的增加，冬红花楸根总长度、根表面积、根体积、根平均直径、根尖数等指标均受到不同程度的抑制，中性盐抑制程度最轻，碱性盐在浓度为200 mmol·L^-1时抑制达到最大，出现表皮脱落、碱蚀等现象；根冠比及根生物量呈降低趋势，中性盐降低幅度较小；丙二醛含量和脯氨酸含量呈上升趋势，超氧化物氢化酶和过氧化物酶呈先上升后下降趋势；胞间CO₂浓度呈现上升趋势，净光合速率、气孔导度及蒸腾速率均呈下降趋势。利用主成分分析筛选出生物量、总根长、根表面积、根体积、根尖数、净光合速率、蒸腾速率、气孔导度可作为‘冬红’花楸耐盐性评价的参考指标。

关键词: 冬红’花楸, 盐碱胁迫, 生长特性, 生理特性, 光合特性