以紫斑牡丹(Paeonia rockii T.Hong et Li J.J.)休眠地下芽为材料,对同一时期打破休眠的地下芽在3种不同培养基上的发育状况、不同时间低温处理后在同一培养基上的发育,以及不同时期休眠地下芽在同一培养条件下的发育进行了比较研究。...以紫斑牡丹(Paeonia rockii T.Hong et Li J.J.)休眠地下芽为材料,对同一时期打破休眠的地下芽在3种不同培养基上的发育状况、不同时间低温处理后在同一培养基上的发育,以及不同时期休眠地下芽在同一培养条件下的发育进行了比较研究。结果表明:MS+BA 1mg/L+NAA0.5mg/L+2,4-D0.5mg/L最有利于打破休眠的地下芽发育;不同低温处理对休眠地下芽的萌发率及发育速率作用明显不同,其中,720h的低温处理效果最佳;彻底打破休眠的不同时期地下芽在同一培养条件下发育速率基本一致。展开更多
Bud dormancy is a complex physiological process of perennial woody plants living in temperate regions,and it can be affected by various phytohormones.Cytokinin oxidase/dehydrogenases(CKXs)are a group of enzymes essent...Bud dormancy is a complex physiological process of perennial woody plants living in temperate regions,and it can be affected by various phytohormones.Cytokinin oxidase/dehydrogenases(CKXs)are a group of enzymes essential for maintaining cytokinin homeostasis,yet a comprehensive analysis of these enzymes in peach remains lacking.Here,a total of 51 CKX members from different species,including six from peach,eleven from apple,nine from poplar,seven from Arabidopsis,eight from strawberry,and ten from rice,were identified using the Simple HMM Search tool of TBtools and a BLASTP program and classified into four groups using phylogenetic analysis.Conserved motif and gene structure analysis of these 51 CKX members showed that 10 conserved motifs were identified,and each CKX gene contained at least two introns.Cis-element analysis of PpCKXs showed that all PpCKX genes have light-responsive elements and at least one hormone-responsive element.The changed relative expression levels of six PpCKX genes in peach buds from endodormancy to bud-break were observed by qRT-PCR.Among them,the expression trend of PpCKX6 was almost opposite that of PpEBB1,a positive bud-break regulator in woody plants,around the bud-break stage.Y1H,EMSA,and dual-luciferase assays indicated that PpEBB1negatively regulated PpCKX6 through direct binding to a GCC box-like element located in the promoter region of PpCKX6.In addition,a transient assay showed that overexpression of PpCKX6 delayed the bud-break of peach.These results indicate that the PpCKX genes play an essential role in the dormancy-regrowth process,and Pp CKX6may act downstream of PpEBB1 directly to regulate the bud-break process,which further improves the hormoneregulatory network of dormancy-regrowth of woody plants,and provides new insights for molecular breeding and genetic engineering of peach.展开更多
文摘以紫斑牡丹(Paeonia rockii T.Hong et Li J.J.)休眠地下芽为材料,对同一时期打破休眠的地下芽在3种不同培养基上的发育状况、不同时间低温处理后在同一培养基上的发育,以及不同时期休眠地下芽在同一培养条件下的发育进行了比较研究。结果表明:MS+BA 1mg/L+NAA0.5mg/L+2,4-D0.5mg/L最有利于打破休眠的地下芽发育;不同低温处理对休眠地下芽的萌发率及发育速率作用明显不同,其中,720h的低温处理效果最佳;彻底打破休眠的不同时期地下芽在同一培养条件下发育速率基本一致。
基金supported by the National Natural Science Foundation of China(32302509)the Weifang University Doctoral Research Launch Fund,China(2022BS18)the National Natural Science Foundation of China(32072518)。
文摘Bud dormancy is a complex physiological process of perennial woody plants living in temperate regions,and it can be affected by various phytohormones.Cytokinin oxidase/dehydrogenases(CKXs)are a group of enzymes essential for maintaining cytokinin homeostasis,yet a comprehensive analysis of these enzymes in peach remains lacking.Here,a total of 51 CKX members from different species,including six from peach,eleven from apple,nine from poplar,seven from Arabidopsis,eight from strawberry,and ten from rice,were identified using the Simple HMM Search tool of TBtools and a BLASTP program and classified into four groups using phylogenetic analysis.Conserved motif and gene structure analysis of these 51 CKX members showed that 10 conserved motifs were identified,and each CKX gene contained at least two introns.Cis-element analysis of PpCKXs showed that all PpCKX genes have light-responsive elements and at least one hormone-responsive element.The changed relative expression levels of six PpCKX genes in peach buds from endodormancy to bud-break were observed by qRT-PCR.Among them,the expression trend of PpCKX6 was almost opposite that of PpEBB1,a positive bud-break regulator in woody plants,around the bud-break stage.Y1H,EMSA,and dual-luciferase assays indicated that PpEBB1negatively regulated PpCKX6 through direct binding to a GCC box-like element located in the promoter region of PpCKX6.In addition,a transient assay showed that overexpression of PpCKX6 delayed the bud-break of peach.These results indicate that the PpCKX genes play an essential role in the dormancy-regrowth process,and Pp CKX6may act downstream of PpEBB1 directly to regulate the bud-break process,which further improves the hormoneregulatory network of dormancy-regrowth of woody plants,and provides new insights for molecular breeding and genetic engineering of peach.
