Budding is an important grafting technique to asexually propagate pecan(Carya illinoinensis(Wangenh.)K.Koch).To determine factors that might hamper success-ful budding of the species,a representative easy-to-survive c...Budding is an important grafting technique to asexually propagate pecan(Carya illinoinensis(Wangenh.)K.Koch).To determine factors that might hamper success-ful budding of the species,a representative easy-to-survive cultivar‘Pawnee’and a typical difficult-to-survive culti-var‘Jinhua’were used for comprehensive analysis.Mor-phological observation showed that cells surrounding the secretory cells or sieve tube had collapsed in‘Jinhua’but not in‘Pawnee’during grafting.‘Jinhua’might suffer more hypoxia stress than‘Pawnee’as‘Jinhua’had higher catalase,superoxide dismutase,polyphenol oxidase,pyruvate decar-boxylase(PDC),alcohol dehydrogenase(ADH)activities during grafting and contained greater levels of hydrogen per-oxide 12 days after grafting(DAG).Transcriptions of PDC and ADH were also up-regulated significantly in‘Jinhua’whereas they were not significantly affected in‘Pawnee’.Phenylalanine ammonia-lyase activities of‘Jinhua’were consistently lower than that of‘Pawnee’.Initial phenol con-tents were similar between the two cultivars.Graft-promot-ing substances,including soluble sugar,soluble protein,and gibberellin(GA)were incompletely recovered in‘Jinhua’12 DAG while fully restored in‘Pawnee’.Increased levels of trans-zeatin riboside in‘Jinhua’were much smaller than in‘Pawnee’3 DAG.The contents of indole-3-acetic acid were similar,and the dynamics of abscisic acid were the same between the two genotypes.Results suggest that hypoxia stress and shortages of sugar,protein,GA,and cytokinin during the healing process might be key factors limiting successful budding of pecan.The degree of scion-rootstock compatibility and the content of phenols might be excluded as constraints for successful budding.展开更多
基金funded by the National Natural Science Foundation of China(3190134732001350)+1 种基金the Central Government Demonstration Project of Forestry Science and Technology(su[2022]TG11)the Key Research and Development Plan of Jiangxi Province(20223BBF61014).
文摘Budding is an important grafting technique to asexually propagate pecan(Carya illinoinensis(Wangenh.)K.Koch).To determine factors that might hamper success-ful budding of the species,a representative easy-to-survive cultivar‘Pawnee’and a typical difficult-to-survive culti-var‘Jinhua’were used for comprehensive analysis.Mor-phological observation showed that cells surrounding the secretory cells or sieve tube had collapsed in‘Jinhua’but not in‘Pawnee’during grafting.‘Jinhua’might suffer more hypoxia stress than‘Pawnee’as‘Jinhua’had higher catalase,superoxide dismutase,polyphenol oxidase,pyruvate decar-boxylase(PDC),alcohol dehydrogenase(ADH)activities during grafting and contained greater levels of hydrogen per-oxide 12 days after grafting(DAG).Transcriptions of PDC and ADH were also up-regulated significantly in‘Jinhua’whereas they were not significantly affected in‘Pawnee’.Phenylalanine ammonia-lyase activities of‘Jinhua’were consistently lower than that of‘Pawnee’.Initial phenol con-tents were similar between the two cultivars.Graft-promot-ing substances,including soluble sugar,soluble protein,and gibberellin(GA)were incompletely recovered in‘Jinhua’12 DAG while fully restored in‘Pawnee’.Increased levels of trans-zeatin riboside in‘Jinhua’were much smaller than in‘Pawnee’3 DAG.The contents of indole-3-acetic acid were similar,and the dynamics of abscisic acid were the same between the two genotypes.Results suggest that hypoxia stress and shortages of sugar,protein,GA,and cytokinin during the healing process might be key factors limiting successful budding of pecan.The degree of scion-rootstock compatibility and the content of phenols might be excluded as constraints for successful budding.