关键词: 棉花生长; 土壤镉污染; 富集特征; 镉积累量

Abstract: 【Objective】 To explore the characteristics of cotton growth and cadmium enrichment under different degrees of cadmium contaminated soil. 【Methods】 The potted plant simulation test method was used to explore the changes of soil pH and cadmium content after cotton planting and the effects of cadmium stress on cotton growth and cadmium accumulation through the addition of cadmium. 【Results】 Cotton roots are acidified, which caused the pH of the rhizosphere soil to decrease. As the concentration of cadmium stress increased, acidification was inhibited, and the available soil cadmium content was significantly reduced. Cotton plant height and aboveground biomass gradually decreased with the increase of cadmium concentration, while the root system was reversed. The cadmium content, transfer coefficient and accumulation of cotton organs increased significantly with the increase of cadmium concentration. Under different cadmium stress, the cadmium enrichment coefficients of cotton roots were all greater than 1. Under 10 mg/kg cadmium stress, the enrichment coefficients of stems, leaves and buds reached 0.98, 0.33, and 0.63 respectively; the cadmium enrichment amounts were 74.01, 39.5, and 98.623 μg/pot respectively, showing strong accumulation capacity. 【Conclusion】 Under cadmium stress, cotton root biomass increases and above-ground biomass decreases. With the increase of cadmium concentration, cotton cadmium accumulation increases. And cotton above-ground cadmium under 5 and 10 mg/kg cadmium stress, the accumulation is significantly higher than that of underground cotton.

Key words: cotton growth; soil cadmium pollution; enrichment characteristics; cadmium accumulation