【摘要】 为探究不同γ-氨基丁酸（γ-aminobutyric acid,GABA）种子处理方式及浓度对大豆萌发期和苗期低温胁迫耐性的影响，筛选确定最佳处理方式与最适浓度，以绥农14为供试大豆品种，GABA浸种浓度分别为0,10,50,100,150,200,250,300,350,400,450和500 mmol·L^-1,GABA包衣浓度也设相同梯度，共24个处理。种子处理后进行低温胁迫。研究显示，GABA浸种和包衣处理均能提高萌发期大豆的低温胁迫耐性，显著增加低温胁迫下大豆种子的萌发率。其中，浸种浓度为400和450 mmol·L^-1及包衣浓度为250和300 mmol·L^-1的GABA处理效果相对较好。基于此，进行苗期试验，设置常温处理（CK）、低温GABA浸种(0,400和450 mmol·L^-1)、低温GABA包衣(0,250和300 mmol·L^-1)共7个处理。发现GABA种子处理显著提高了低温胁迫下苗期大豆SOD、CAT和APX活性，降低了O-2及MDA含量，提高了脯氨酸含量，缓解了低温胁迫对大豆幼苗的损伤。其中，与GABA包衣浓度为0 mmol·L^-1的包衣处理相比，GABA包衣浓度为300 mmol·L^-1的大豆叶片SOD、POD、CAT和APX活性均显著增加，分别增加56.8%、100%、71.8%和82.7%。MDA含量降低25.3%，脯氨酸含量增加29.7%。因此，300 mmol·L^-1GABA包衣处理可显著缓解低温对大豆种子萌发的抑制作用，增强大豆幼苗的抗氧化能力，对大豆萌发期与苗期低温胁迫耐性的提升效果最为显著。更多还原

【Abstract】 To investigate the effects of different GABA（γ-aminobutyric acid） seed treatment methods and concentrations onthe cold stress tolerance of soybeans during the germination and seedling stages, and to determine the optimal treatmentmethod and concentration, the variety Suinong 14 was used as the test material, and different seed treatments were applied.GABA soaking concentrations were set at 0, 10, 50, 100, 150, 200, 250, 300, 350, 400, 450, and 500 mmol·L^-1, andGABA coating concentrations were set at the same gradient, totaling 24 treatments. After seed treatment, cold stress wasapplied. The study showed that both GABA soaking and coating treatments improved the cold stress tolerance of soybeansduring the germination stage, significantly increasing the germination rate of soybean seeds under cold stress. Among them,GABA treatments with soaking concentrations in the range of 400 and 450 mmol·L^-1and coating concentrations in the range of250 and 300 mmol·L^-1showed relatively better effects. Based on these findings, a seedling stage experiment was conducted,including normal temperature treatment（CK）, cold stress with GABA soaking(0, 400, and 450 mmol·L^-1), and coldstress with GABA coating(0, 250, and 300 mmol·L^-1), totaling 7 treatments. The results revealed that GABA seedtreatment significantly enhanced the activities of SOD, CAT, and APX in soybean seedlings under cold stress, reduced thecontents of O-2and MDA, increased the proline content, and alleviated the damage caused by cold stress on soybeanseedlings. Specifically, compared to the treatment with a GABA coating concentration of 0 mmol·L^-1, the soybean leavestreated with a GABA coating concentration of 300 mmol·L^-1showed significant increases in SOD, POD, CAT, and APXactivities, by 56. 8%, 100%, 71. 8%, and 82. 7%, respectively. The MDA content decreased by 25. 3%, while the prolinecontent increased by 29. 7%. Therefore, the 300 mmol·L^-1GABA coating treatment significantly alleviated the inhibitory effectof low temperature on soybean seed germination, enhanced the antioxidant capacity of soybean seedlings, and demonstrated themost pronounced improvement in cold stress tolerance during both the germination and seedling stages of soybeans.更多还原