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为了解不同基因型苎麻在镉胁迫下变化差异性，以对镉积累能力不同的3个苎麻品种‘中苎1号’、‘华苎5号’、‘川苎8号’为试验材料，采用温室盆栽试验，研究了5、25、50 mg/L镉胁迫对苎麻生物量、叶片SPAD值及光合特性的影响。试验结果表明：（1）镉处理会抑制苎麻生长和光合作用，株高、生物量、SPAD值、光合参数都受镉胁迫而下降；（2）不同基因型苎麻受镉胁迫时生长变化不一致，苎麻对镉的敏感性由高到低为‘中苎1号’＞‘川苎8号’＞‘华苎5号’。低浓度(5 mg/L)镉胁迫对3种基因型苎麻生长有显著促进作用；‘中苎1号’的生长在中、高浓度(25~50 mg/L)镉胁迫下显著被抑制，华苎5号’和‘川苎8号’生长受镉浓度变化影响低于‘中苎1号’，生长较稳定。（3）不同浓度镉对苎麻光合特性各参数值影响不一致，参数值变化幅度与镉浓度相关性不大，苎麻光合速率的降低主要限制因素是非气孔因素，3个基因型对镉胁迫时光合参数响应反应不一致。“,”To study the difference of different genotypes of ramie under cadmium stress, ‘Zhongzhu 1’, ‘Huazhu 5’ and ‘Chuanzhu 8’ were used as experimental materials, which had different cadmium accumulation ability. The influences of Cd stress (5, 25 and 50 mg/L) on ramie biomass, leaf SPAD value and photosynthetic characteristics were studied in greenhouse. The results showed that: (1) cadmium treatment inhibited the growth and photosynthesis of ramie, plant height, biomass, SPAD value and photosynthetic parameters decreased under cadmium stress; (2) the growth of different genotypes of ramie was different under cadmium stress, and the sensitivity of ramie to cadmium followed the order of ‘Zhongzhu 1’＞ ‘Chuanzhu 8’＞ ‘Huazhu 5’, low concentration cadmium could promote ramie growth; the growth of ‘Zhongzhu 1’ was significantly inhibited under 25-50 mg/L cadmium treatment, the effect on ‘Huazhu 5’ and ‘Chuanzhu 8’ was lighter and more stable; (3) the effect of different concentrations of cadmium on the photosynthetic characteristics of ramie was not consistent, and the indexes were not correlated with the concentration, the main limiting factor of the decrease of photosynthetic rate of ramie was non-stomatal factor, and the responses of the three genotypes to photosynthetic parameters of cadmium stress were inconsistent.