【摘要】 【目的】探明菌根对蒙古扁桃(Prunus mongolica)抗旱能力影响的分子机制。【方法】对生长45 d的菌根化蒙古扁桃与非菌根化蒙古扁桃进行非干旱胁迫和干旱胁迫处理,非干旱胁迫蒙古扁桃在处理期间每天补充水分;干旱胁迫处理蒙古扁桃从培育45 d开始停止浇水,模拟自然干旱胁迫,持续时间15 d。试验结束后,每个处理选12株进行叶长、叶宽、叶片脱落数及生物量的测定和统计;另选12株采用高通量测序方法进行转录组测序,并对其差异表达转录本进行GO和KEGG富集分析。【结果】干旱胁迫条件下,菌根化苗木底部的一些叶片会脱落,而非菌根化苗木叶片几乎不脱落;同时,菌根化苗木的地下生物量显著高于非菌根化苗木。通过高通量测序发现,4个处理文库共获得43 641个转录本;在P<0.001时,菌根化蒙古扁桃干旱胁迫(MD)与非干旱胁迫(MCK)处理相比,存在820个差异表达转录本;干旱胁迫条件下,菌根化苗木(MD)与非菌根化苗木(ND)相比,存在3 751个差异表达转录本;非干旱胁迫条件下,菌根化苗木(MCK)与非菌根化苗木(NCK)相比,存在2 315个差异表达转录本。GO富集分析发现,MD与ND处理文库间的细胞组分、分子功能和生化过程3类主要功能分类的差异表达转录本,较MD与MCK处理文库间均增加;MCK与NCK处理文库间差异转录本的分类结果同MD与ND处理文库间基本相同,只是在分子功能分类中多出通道调节活性这一功能。经KEGG富集分析发现,天线蛋白、类胡萝卜素生物合成途径、激素信号传导途径、N代谢途径、过氧化物酶体、植物昼夜节律和MAPK信号途径等与干旱胁迫存在密切联系。实时荧光定量PCR表明转录组测序数据可靠。【结论】菌根化处理可以提高蒙古扁桃的抗旱能力。更多还原

【Abstract】 【Objective】 This study aimed at exploring the molecular mechanism of mycorrhiza on drought resistance of Prunus mongolica.【Method】 The mycorrhizal P. mongolica and non-mycorrhizal P. mongolica almonds were treated with non-drought stress and drought stress for 45 days.The non-drought stress seedlings were replenished with water every day during the treatment to maintain the maximum water holding capacity(48.7%).The watering for seedlings in drought stress treatment were stopped 45 days after cultivation,and the natural drought stress was simulated for 15 days.After 60 days,twelve seedlings were selected from each treatment to measure and count leaf length,leaf width,leaf abscission number and biomass.Twelve seedlings were sequenced by high-throughput sequencing and their differentially expressed transcripts were analyzed by GO and KEGG enrichments.【Result】 Under drought stress,some leaves at the bottom of mycorrhizal seedlings fell off,while non-mycorrhizal seedlings barely fell off.The underground biomass of mycorrhizal seedlings was significantly higher than that of non-mycorrhizal seedlings.A total of 43 641 transcripts were obtained from the four processed libraries by high-throughput sequencing.At P<0.001,there were 820 differentially expressed transcripts in mycorrhizal P. mongolica under drought stress(MD) and non-drought stress(MCK) conditions.There were 3 751 differentially expressed transcripts compared to MD and non-mycorrhizal(ND) seedlings under drought stress.There were 2 315 differentially expressed transcripts in MCK and non-mycorrhizal seedlings(NCK) under non-drought stress conditions.GO enrichment analysis showed that the differential expression transcripts of the three major functional categories of cellular components,molecular functions and biological processes were increased between the MD and ND processing libraries compared to the MD and MCK processing libraries.The classification results of differential transcripts between MCK and NCK processing libraries were basically the same between MD and ND,but it only had a function of channel regulation activity in the molecular function classification.The KEGG enrichment analysis showed that antenna protein,carotenoid biosynthetic pathway,hormone signaling pathway,nitrogen metabolic pathway,peroxisomes,circadian rhythm-plant and MAPK signaling pathway were closely related to drought stress.Real time quantitative PCR showed that transcriptome sequencing data were reliable.【Conclusion】 Mycorrhiza can improve the drought resistance of P. mongolica.更多还原