The most sustainable approach to overcome iron deficiency in fruit crops is breeding for rootstocks with a higher capability to acquire iron (Fe) from the soil. The objective of this study was quantitative trait loci (QTL) and candidate gene analyses of rootstock-mediated low-Fe tolerance in terms of fruit yield and quality traits, including Fe fruit content, in a satsuma mandarin-grafted rootstock population derived from a cross between Citrus reshni (Cleopatra mandarin) and Poncirus trifoliata, under sufficient and low-Fe fertilization (15.3 vs 5.2 μM Fe, respectively). Iron reduction to one-third significantly decreased satsuma leaf chlorophyll concentration, fruit iron concentration, and the fruit/leaf iron proportion. Thirty-four QTLs were detected for 46 heritable traits. Eighteen of them were also found significant when testing each parental genome separately. Seven QTLs contributed to the fruit concentrations of Cu, Fe, K, Na, and S. QTLs involved in rootstock mediated tolerance to Fe deficiency and fruit quality traits distributed into five genomic regions whose gene contents (assuming collinearity with the C. clementina genome) were investigated for overrepresented molecular functions and biological processes, and putative functional candidates. Among them, a metal-NA-transporter YSL3 (Ciclev 10019170m), four phytochelatin synthases, an iron-chelate-transporter ATPase, and four basic/helix-loop helix genes coding for likely relevant transcription factors in Fe homeostasis under Fe deficiency were found as follows: bHLH3 (Ciclev10019816m), bHLH137.1 (Ciclev10031873m), bHLH123 (Ciclev10008228m), and ILR3 (Ciclev10009354m). Genes within three QTL regions supported a genetic connection between rootstock-mediated tolerance to Fe deficiency and biotic stresses in citrus.

克服水果作物中铁缺乏症的最可持续的方法是育种具有更高能力从土壤中获取铁（Fe）的砧木。这项研究的目的是定量分析了杂交后代的萨萨玛柑嫁接砧木群体中砧木介导的低铁耐性的定量性状位点（QTL）和候选基因分析，分析了其产量和品质性状，包括铁果含量，对砧木介导的低铁耐性在柑橘柑桔（Cleopatra普通话）和Poncirus trifoliata之间，在充分和低铁的施肥条件下（分别为15.3和5.2μMFe）。铁减少到三分之一会显着降低饱和状态叶片的叶绿素浓度，果实铁浓度和果实/叶铁比例。检测到34个QTL，共46个遗传性状。当分别测试每个亲本基因组时，还发现其中18个具有重要意义。七个QTL促进了果实中Cu，Fe，K，Na和S的浓度。参与砧木介导的对Fe缺乏和水果品质性状的QTL分布在五个基因组区域，其基因含量（假设与C. clementina共线性）基因组）进行了研究，以研究过度代表的分子功能和生物学过程以及假定的功能候选物。其中，发现了金属-NA-转运蛋白YSL3（Ciclev 10019170m），四个植物螯合酶合酶，一个铁螯合物-转运蛋白ATPase和四个基本/螺旋环螺旋基因，这些基因编码Fe缺乏下Fe稳态中可能的相关转录因子。如下所示：bHLH3（Ciclev10019816m），bHLH137.1（Ciclev10031873m），bHLH123（Ciclev10008228m）和ILR3（Ciclev10009354m）。三个QTL区域内的基因支持砧木介导的对铁缺乏的耐受性与柑橘的生物胁迫之间的遗传联系。