盐胁迫对大豆种子萌发及生理的影响

Influence of Salt Stress on Germination and Physiology of Soybean Seeds

选取有代表性的中性盐NaCl,设置0、50、100、150、200 mmol/L 5个浓度水平,对山西普遍种植的大豆种子进行萌发胁迫处理,探讨大豆种子萌发期耐盐性以及耐盐机制。结果表明,低盐浓度(50 mmol/L)对种子萌发有促进作用,而高盐浓度抑制萌发,且随着NaCl浓度的增高,抑制程度明显加重;胚根胚芽中SOD和POD活性呈先升高后降低的趋势,而Pro和MDA含量则呈逐渐增加的趋势。大豆种子在发芽和生理变化上均表现出一定的耐盐能力,相比较而言,POD在其萌发期抵御盐胁迫时起重要作用。

To discuss the adaptability of soybean seeds to salt stress and the adaptive mechanism,the germination tests of most common breeds treated with 0,50,100,150 and 200 mmol/L salt stress(NaCl) were conducted in growth chambers.The results showed that low salt stress(50 mmol/L NaCl) promoted the seed germination,but high stress inhibited it and the inhibitive effects obviously increased with the increasing of NaCl concentration.The activity of SOD and POD in radicals and embryos of soybean seeds increased firstly and then decreased but the proline and MDA contents significantly increased as the NaCl concentration increased.These results indicated that soybean seed could survive on medium containing 50-100 mmol/L NaCl.By comparison,POD played a major role in resisting salt stress at germination stage.