Polyploids exhibit different phenotypes compared to those of diploids in plants, and the important role of polyploids in tree breeding has been widely recognized. The transcriptomes detected by RNA-seq in the Populus triploid by doubling the chromosomes of the female gamete, in the triploid by doubling the chromosomes of somatic cells and the diploid with the parent were compared to reveal the patterns of gene expression of tetraploid leaves and their influence on growth. The results showed that the high expression of GATA and PORA in tetraploid leaves was the reason for the higher chlorophyll content in the leaves than in diploid and triploid leaves. The 11-day-old tetraploid leaves began to enter the aging stage. Compared with that in the diploid, GRF was significantly upregulated, while the amylase genes were downregulated. Compared with those in the triploid, 3 STN7 genes that regulate photosynthetic genes and PGSIP genes which are related to starch synthesis, were significantly downregulated in the tetraploid, and the auxin receptor protein TIR1 was also significantly downregulated. In the tetraploid, auxin-regulating genes such as GH3 and AUX/IAA as well as genes involved in the regulation of leaf senescence, SAG genes and SRG genes were significantly up-regulated, resulting in a decrease in the auxin content. In senescent leaves, CHLD, CHLI1, and CHLM in the early stage of chlorophyll synthesis all began to downregulate their expressions, leading to the downregulation of LHC genes and a decrease in their photosynthetic efficiency, which led to the downregulation of carbon fixation-related genes such as SS genes, thus affecting carbon synthesis and fixation. This finally led to the slow growth of tetraploid plants. These data represent the transcriptome characteristics of tetraploid, and they can be used as a resource for further research on polyploids and provide a reference for further understanding of the function of polyploid vegetative growth-related genes.

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四倍体胡杨叶片基因差异表达的研究

与植物中的二倍体相比，多倍体表现出不同的表型，并且多倍体在树木育种中的重要作用已得到广泛认可。比较了三倍体毛白杨通过雌性配子的染色体，三倍体中体细胞和双倍体的染色体与亲本的RNA-seq检测的转录组，从而揭示了四倍体叶片的基因表达模式及其对增长的影响。结果表明，四倍体叶片中GATA和PORA的高表达是叶片中叶绿素含量高于二倍体和三倍体叶片的原因。11天大的四倍体叶片开始进入衰老阶段。与二倍体相比GRF被显着上调，而淀粉酶基因被下调。与三倍体相比，在四倍体中调节与淀粉合成有关的光合作用基因和PGSIP基因的3个STN7基因被显着下调，而生长素受体蛋白TIR1也被显着下调。在四倍体中，生长素调节基因如GH3和AUX / IAA以及参与叶片衰老调节的基因，SAG基因和SRG基因被显着上调，导致生长素含量降低。在衰老的叶片中，CHLD，CHLI1，叶绿素合成早期的CHLM和CHLM都开始下调它们的表达，导致LHC基因的下调和它们的光合效率降低，从而导致碳固定相关基因（例如SS基因）的下调，从而影响了碳。合成和固定。最终导致四倍体植物生长缓慢。这些数据代表了四倍体的转录组特征，可作为进一步研究多倍体的资源，并为进一步了解多倍体与营养生长相关的基因的功能提供参考。