Inverse Development Of Maize Inflorescence And In Situ Analysis Of Hormones

Inflorescence is an important reproductive organ of plants.The development of inflorescence plays an important role in the life cycle of maize,and is also the decisive factor in the establishment of grain.Hormone is an important factor regulating the differentiation and development of inflorescence.In this study,the pair of sisters of the embryonic reverse-specific germplasm SN110 of the maize-seedlings toward the tip of the ear and the embryonic reverse-specific germplasm SN112 of the maize-seedlings toward the ear-stalk were used as materials to investigate the orientation of SN110 and SN112 grain embryos through agronomic traits.Identification;SN110 and SN112 inflorescence developmental dynamics were analyzed by paraffin sectioning technique and scanning electron microscopy technique;SN110 and SN112 inflorescence differentiation were used in different stages of auxin,gibberellin,cytokinin and abscisic acid in maize by immunofluorescence tissue localization technique.The temporal and spatial changes of female inflorescence differentiation were analyzed.High performance liquid chromatography-tandem mass spectrometry(HPLC-MS)was used to analyze the growth factors,gibberellins,cytokinins and abscisic acid of SN110 and SN112 female inflorescences at different stages.Quantitative detection,to determine the developmental dynamics of grain embryos in the forward and reverse directions,and to explore the causes of the reverse development of grain embryos and the relationship with plant hormone levels.The main findings are as follows:1.By evaluating the agronomic traits such as SN110 and SN112,it was clarified that the SN110 grain embryo was oriented toward the tip of the ear as the grain embryo forward material,and the SN112 grain embryo was the grain embryo reversal material toward the ear stalk end.2.Paraffin sectioning and scanning electron microscopy were used to trace the inflorescence development of SN110 and SN112.It was confirmed that the SN112 floret differentiation stage was the key period of grain embryo reversal,which showed that the lower florets preferentially developed the upper florets and gradually aborted,two smallflowers.An angle of 180°is formed.3.Immunofluorescence tissue localization technique and high performance liquid chromatography-tandem mass spectrometry(HPLC-MS)were used to analyze the distribution and content of auxin,gibberellin,cytokinin and abscisic acid in SN110 and SN112 female inflorescence differentiation.Analysis,the ratio of endogenous hormone content of SN112(GA4/ABA,GA9/ABA,ZR/ABA,IAA/ABA)was significantly stronger than that of SN110,which was the direct cause of SN112 grain embryo toward the stem.