土壤pH值对甜菜幼苗生理变化的影响

Effects of soil pH on physiological changes in sugar beet seedlings

为了解不同酸碱性条件下甜菜种子发芽、幼苗生长及生理响应变化,通过室内盆栽实验,设置土壤pH值9组处理,测定甜菜种子发芽、幼苗生长及生理指标变化。结果表明:甜菜发芽率以pH值为9.5的碱性土为最高,达到95.83%。甜菜幼苗干重以pH值9.5时达到最大,根和叶的超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)活性和可溶性蛋白、还原糖、脯氨酸、游离氨基酸含量在pH值为5.0土壤最高,pH为9.5时达到最低。同时甜菜不同pH值和抗氧化酶活性、渗透调节物质含量呈现显著负相关。在酸性条件下,甜菜幼苗生长受到抑制,并出现逆境胁迫响应变化,而在pH为9.5的偏碱性土壤下幼苗生长状况较好。

To understand the changes of sugar beet seed germination as well as seedling growth and physiological response under different acid and alkaline conditions,an indoor pot experiment with nine groups of soil pH treatments.The results showed that the germination rate of sugar beet reached the highest 95.83%in alkaline soil of pH 9.5.It was found that the dry weight of sugar beet seedlings reached the maximum at pH 9.5,and the superoxide dismutase(SOD),peroxidase(POD),catalase(CAT),ascorbate peroxidase(APX)activities,soluble protein,reducing sugar,proline and free amino acid contents of roots substance and leaves reached highest pH 5.0 and lowest at pH 9.5.Meanwhile,different pH of sugar beet showed significant negative correlation with antioxidant enzyme activity and osmoregulatory content.Under acidic conditions,sugar beet growth was inhibited and changes in response to adversity stress were observed.In contrast seedling growth was better in a more alkaline soils of around pH 9.5.