MdFLP及其上游调控蛋白响应重力信号调控苹果自根砧不定根GSA形成研究

苹果是我国农业支柱产业之一，自根砧木是目前高标准建园的首选项。但是自根砧不定根为茎源根系，无主根，分布浅，适应性和抗性均较差，在我国干旱瘠薄果园中表现欠佳，主要原因在于自根砧不定根向重力性定点角（Gravitropic set-point angle，GSA）的发育与实生砧有较大的差异。.采用我们选育的不同GSA苹果自根砧优系作为试验材料，利用不同GSA的苹果自根砧优系根系转录组测序分析和酵母单杂交、GUS瞬时表达、EMSA等生化技术已经验证MdFLP是调控苹果自根砧不定根GSA形成的关键调控因子，然而在苹果自根砧不定根GSA形成过程中，MdFLP及其上游调控蛋白MdARF19如何响应重力信号，表达影响苹果自根砧不定根IAA的分布进而调控GSA的形成尚不清楚，因此解析MdFLP调控苹果自根砧不定根GSA形成的生化、分子机理，以期为苹果自根砧分子设计育种提供理论基础及技术支持。

Apple is one of the mainstay industries of agriculture in China. However, the adventitious roots of self - rootstock are stem source roots, no principal roots and shallow distribution, poor adaptability and resistance, and display poor performance in dry barren orchards in China. The main reason is that the development of adventitious roots Gravitropic Set-point Angle (GSA) has a big difference comparing with seedlings..With our selection of different GSA apple self-root stock as test materials, using different GSA apple self- root stocks for transcriptome sequencing analysis and yeast single hybridization, GUS transient expression, EMSA we prove that MdFLP is the key regulatory factors for the formation of adventitious roots GSA, however, in the course of the adventitious roots GSA evolution, we still do not verify that MdFLP and its upstream regulatory protein( MdARF19) response gravity signal, adjust distribution of IAA and control the formation of the GSA. Therefore, the biochemical and molecular mechanism of MdFLP regulating the formation of GSA in adventitious roots of apple self-root stock will be analyzed, so as to provide theoretical basis and technical support for molecular design and breeding of apple self-root stock.