土壤pH对琯溪蜜柚叶片枝条和果实的影响

Effects of soil pH on leaf branch and fruit of Citrus grandis (L.) Osbeck. cv. Guanximiyou

探讨土壤pH对琯溪蜜柚枝条、叶片和果实粒化的影响,为琯溪蜜柚科学种植和可持续发展提供理论支持。选取不同土壤pH但立地条件和果树长势较为均匀的4组琯溪蜜柚果园(土壤pH分别为5.15、4.76、4.73和4.49),对琯溪蜜柚叶片和枝稍进行Illumina HiSeq 4000高通量转录组测序分析,筛选出差异基因进行KEGG富集代谢通路分析,并测定相关指标。结果表明:较低土壤pH(4.76、4.73和4.49)加重了琯溪蜜柚果实的粒化,影响了琯溪蜜柚叶片和枝条MAPK信号转导、植物激素信号转导通路;土壤pH显著影响枝条的次生代谢、半乳酸代谢等途径;对信号转导通路中丝裂原活化蛋白激酶激酶激酶18、蛋白磷酸酶2C、脱落酸不敏感蛋白5、CML46钙结合蛋白、生长素应答蛋白IAA1和内切几丁质酶等相关基因进行PCR荧光定量分析,验证了转录组数据的可靠性;土壤pH影响了叶片和果实中脱落酸含量,也影响枝条中生长素含量。本研究表明,果园较低土壤pH加重琯溪蜜柚果实的粒化,影响了果实、叶片和枝条中部分植物激素含量,影响了与植物激素信号相关转导通路中基因的表达。

Exploring the effects of soil pH on the branches,leaves,and juice sac granulation in fruits of Citrus grandis(L.)Osbeck.cv.Guanximiyou provides theoretical support for its scientific cultivation and sustainable development.We carried out an experiment in four Guanximiyou orchards that showcased a uniformity in geographical conditions and tree growth but differed in soil pH(soil pH values were 5.15,4.76,4.73 and 4.49,respectively).Illumina HiSeq 4000 highthroughput transcriptome sequencing analysis was performed on the leaves and branches of Guanximiyou,with the aim of isolating differential genes for KEGG enrichment metabolic pathway analysis and identifying associated indicators.The findings showed that a lower soil pH(4.76,4.73 and 4.49)exacerbated the granularity of Guanximiyou and affected the MAPK signal transduction and plant hormone signal transduction pathways in leaves and branches.Furthermore,soil pH significantly influenced secondary and lactic acid metabolic pathways in branches.Concurrently,a PCR fluorescent quantitative analysis of pertinent genes in signal transduction pathways,such as MAP Kinase Kinase Kinase 18,Protein Phosphatase 2C,Abscisic Acid Insensitive Protein 5,CML46 Calcium Binding Protein,Auxin Response Protein IAA1,and EndoChitinase,was conducted to validate the reliability of the transcriptome data.Soil pH was found to influence the quantities of abscisic acid in leaves and fruits,and the amount of auxin in branches.We conclude that lower soil pH exacerbates the granularity of Guanximiyou,influences the quantities of hormones in fruits,leaves and branches and the expression of genes involved in plant hormone signaling transduction pathways.