Application Of Plant Growth Regulator In Soybean Root System At Early Growth Stage And Construction Of Gibberellin Electrochemical Detection Platform

Plant growth regulators play different functions during plant growth and development such as seed germination,embryo development,fruit maturation and dormancy.Gibberellin and Uniconazole are widely used in a variety of plants.In order to further explore the effects of the two plant growth regulators on the physiological morphology and endogenous hormone content of plants,the soybean variety"Zhong Huang 37"was used as the test material.800μmo L·L-1 gibberellin and 4μmo L·L-1uniconazole were used for seed soaking treatment,and relevant index sampling was carried out at 48 h,72 h,and 96 h to analyze the root parameters of soybean seedlings and the content of endogenous hormones.Variety.During the experiment,it was found that high performance liquid chromatography could not test the content of gibberellin（GA₃）.Therefore,this study prepared a label-free electrochemical immunosensor to test the content of gibberellin in soybean roots.Electrochemical immunosensors were prepared from materials such as carboxylated graphene（COOH-GR）,carbon nanotubes（COOH-MWNT）,and polydopamine（PDA）with good biocompatibility and large specific surface area,and expanded experiments were carried out to construct Immunosensing platform.The test results are as follows:（1）IAA,JA,SA after treatment with 4μmo L·L-1 Uniconazole all reached higher levels at 48 h,while IAA,JA,SA after G0 treatment all reached higher levels at 72 h,G800 After treatment,IAA,JA,and SA all reached a high level at 96 h,and the root length,root area,and root tip number under different treatments were all S4>G0>G800,which was consistent with the results of root morphology index,G800 treatment The ABA content in the roots of the later soybeans was lower than that of S4,while the growth of G0 in root morphology was worse than that of S4.The test results show that during the germination period of soybeans,after being treated with plant growth regulators,the morphological changes of the roots can be adjusted by causing changes in the concentration of hormones.IAA,JA,and SA play a growth-promoting role.There is a certain antagonistic relationship between ABA and gibberellin to affect growth.And the morphological characteristics and hormone changes together confirmed that the two plant growth regulators are time-effective.（2）The prepared electrochemical immunosensor not only has high sensitivity and large detection range（100 a M-1 m M）,but also has a lower detection limit（17.4 am（S/N=3））.The prepared electrochemical immunosensor was applied to the detection of soybean seedlings treated with different growth regulators,and RT-PCR was used for verification,and consistent experimental results were also obtained.In order to verify the successful construction of the immunosensing platform,the gibberellin（GA₃）monoclonal antibody was replaced with the abscisic acid monoclonal antibody,and the abscisic acid concentration test was performed under the optimal experimental conditions of the gibberellin label-free electrochemical immunosensor.A wider detection range（100 a M-100μM）and a lower detection limit（0.224 am（S/N=3））were also obtained.Confirmed the successful construction of the label-free electrochemical immunosensing platform.