镉胁迫下硅对草莓生长及生理特性的影响

Effects of Silicon on Growth and Physiological Characteristics of Strawberry(Fragaria ananassa Duch.)Under Cadmium Stress

在中和硅酸钾的碱性和消除钾离子影响的基础上,通过水培试验研究了镉胁迫下硅对草莓生长及生理特性的影响。结果表明:供硅可减轻镉对草莓叶片的伤害,提高镉胁迫下植株的相对生长速率和根冠比,增加植株生物量;硅能提高光合色素含量,降低镉胁迫下草莓叶片和根系的质膜透性,使叶片丙二醛含量减少,减轻膜脂过氧化程度;适量浓度的硅可使游离脯氨酸和可溶性糖含量保持在一定水平,保证植株在镉胁迫条件下对水分的吸收和利用;镉胁迫下,草莓叶片SOD、POD、CAT活性降低,供硅可提高SOD、POD、CAT活性,减轻活性氧及自由基对草莓叶片的毒害。上述结果说明,供硅改善了草莓逆境生理状况,缓解了镉的毒害作用,促进了草莓的生长发育。

The water culture experiment of strawberry growth and physiology at different silicon levels under cadmium stress was conducted,and the H2SO4 was used to neutralize the alkalinity of K2SiO3,and the different concentration of SO2-4 and K＋ between treatments was balanced with the addition of K2SO4,thus the effect of pH and accompanying ions by added silicate on cadmium was eliminated.The results showed that silicon supplying relieved injury on strawberry and promoted its plant biomass under cadmium stress.Silicon could increase the content of photosynthetic pigments,lower leaves permeability of plasma membrane,decrease the content of MDA and alleviate the grate of membrane lipid peroxide.The effects of silicon also maintained the content of free proline and soluble sugar in certain level,promoted the activity of SOD,POD and CAT,reliefed the poisoning effects of active oxygen and free-radicals to strawberry leaves.These results suggested that sili-con supplying could improve physiological characteristics of strawberry and promote the growing of strawberry by alleviating the toxicity of cadmium.