黄瓜植株与愈伤组织对铜的耐受及其铜积累研究

Copper Tolerance and Its Accumulation in Cucumber Plants and Calli

以黄瓜[cucumis sativus L.]品种优丰早为试材,研究不同铜浓度处理下黄瓜植株和愈伤组织的生长状况及铜在其内的积累与分布情况。结果表明:①10 mg/L铜处理组黄瓜植株生长正常,茎中铜累积浓度达到865mg/kg干重,高于根和叶中铜累积浓度;20 mg/L以上铜处理组黄瓜植株出现明显的铜毒害现象,其根中铜累积浓度超过茎叶,均超过1 500 mg/kg干重,高于10 mg/L铜处理组,但其茎中铜累积浓度低于10 mg/L处理组。②黄瓜愈伤组织能耐受10～40 mg/L的铜胁迫,但其生长均明显受到抑制;愈伤组织对铜的吸收积累较快,铜积累量一般在第3周达到最大值,此后会有所下降;愈伤组织铜积累量与铜处理浓度正相关,最高积累量可达2 350 mg/kg;愈伤组织的细胞壁、细胞器和细胞可溶部分都能积累铜,在较低浓度铜胁迫下,细胞壁是主要积累部位,而在较高浓度铜胁迫下,细胞可溶部分是铜的主要积累部位。

The growth status of cucumber plants and calli in different concentrations of copper, and the accumulation and distribution of copper in them were studied. The resuhs showed： 1） Cucumber plants treated with 10 mg/L Cu treatment grew normally, and the copper accumulated in the stem was 865 mg/kg dry weight, higher than that in roots and leaves. Cucumber plants showed copper toxicity in the treatment of 20 mg/L and more, and copper cumulated more in roots than in shoots, which was over 1 500 mg/kg dry weight, but the copper accumulation in stems was lower than that in 10 mg/L Cu treatment. 2） Cucumber calli could bear the copper stress of 10 -40 mg/L, but their growth were clearly influenced. The copper absorption and accumulation of calli were quick, reaching its maximum in the third week. Calli copper accumulations and copper concentration were positively correlated, and the maximum accumulation could reach 2 350 mg/kg. Cell wall, organelles and soluble fraction in cells could accumulate copper. In low concentrations of copper stress, cell wall was the main site of the accumulation, but at higher concentrations of copper stress, the major part of the accumulation was the soluble fractions.