盐碱胁迫下GF677和毛桃根部显微观察和比较转录组分析

Scanning Electron Microscopy Observation and Comparative Transcriptome Analysis of Roots of GF677 and Maotao in Response to Saline-Alkali Stresses

土壤盐碱化已成为危害植物生长的重要因素之一。本研究中,我们对盐碱胁迫下两种桃树(GF677和毛桃)的根部分别进行细胞学观察和比较转录组分析。扫描电子显微镜结果表明GF677根部的根毛密度要显著多于毛桃根部。比较转录组分析显示在|log2 Ratio|≥1和Probability>0.8的阈值下共检测到1 379个基因差异表达,其中279个上调,1 100个下调。对差异表达基因进行Gene ontology(GO)聚类共得到27个小类显著富集。Pathway富集分析显示脯氨酸代谢、类黄酮代谢和氧化磷酸化代谢等通路在GF677中被显著激活,暗示了GF677可能通过提高渗透压和维持氧化还原平衡使植物体免受盐碱胁迫的危害。研究结果为耐盐碱基因挖掘以及桃树耐盐碱分子改良育种提供了理论依据。

Soil salinity is one of serious problems that harmful to plant growth around the world. In the present study, we analyzed the changed of roots of two peach clones （GF677 and Maotao） upon saline-alkali stresses by using cytological study and comparative transcriptome analysis. Scanning electron microscopy （SEM） observation showed that the density of root hair of GF677 was higher than that of Maotao. Comparative transcriptome analysis detected 1 379 genes with differential expression （including 279 up-regulation and I 100 down-regulation） under the limit rule with Ilog2 Ratio]〉l and probability〉0.8. Based on the results of Gene ontology （GO）, 27 functional groups were significantly enrichment. Pathway enrichment analysis showed that the biological pathways as ＂proline metabolism＂, ＂flavonoids metabolism＂, ＂oxidative phosphorylation metabolism＂ were notably activated in GF677, hinting that it is possible to protect GF677 against salt and alkali stresses by increasing osmotic pressure and maintaining redox balance. The results list here provided a theoretical basis for cloning saline-alkali tolerant genes and molecular breeding for improving salt tolerance in peach.