title: Effects of grafting with pumpkin rootstock on carbohydrate metabolism in cucumber seedlings under Ca(NO3)2 stress.
abstract: This study investigated the effects of grafting on the carbohydrate status and the enzymes of carbohydrate metabolism in self-grafted and grafted cucumber seedlings using the salt-tolerant pumpkin rootstock 'Qingzhen 1' (Cucurbita maxima × Cucurbita moschata) under 80 mM Ca(NO3)2 stress for 6 d. The growth of self-grafted seedlings was significantly inhibited after the treatment of Ca(NO3)2 stress, whereas the inhibition of growth was alleviated in pumpkin rootstock-grafted seedlings. Ca(NO3)2 stress increased the contents of the total soluble sugar, sucrose and fructose, but decreased the starch content in rootstock-grafted leaves. However, compared with self-grafted plants, rootstock-grafted seedlings were observed with a higher content of sucrose and total soluble sugar (TSS) under salt stress. Rootstock-grafted seedlings exhibited higher activities of acid invertase (AI), neutral invertase (NI) and phosphate sucrose synthase (SPS) of sucrose metabolism in leaves than that of self-grafted seedlings under salinity. Moreover, the activities of fructokinase (FK), hexokinase (HK), phosphofructokinase (PFK) and pyruvate kinase (PK) of glycolysis were maintained at a higher level in leaves of rootstock-grafted seedlings after Ca(NO3)2 stress. Additionally, rootstock-grafting decrease the high percentage enhancement of key enzymes gene expression in glycolysis in the scion leaves of cucumber seedlings induced by salt stress. These results suggest that the rootstock-grafting improved salt tolerance, which might play a role in elevated sucrose metabolism and a glycolytic pathway regulated by the pumpkin rootstock.
authors.affiliation: College of Horticulture, Nanjing Agricultural University, Key Laboratory of Southern Vegetables Genetic Improvement of Ministry of Agriculture, Nanjing 210095, PR China. Electronic address: 2012104051@njau.edu.cn.
authors.forename: Wen-wen
authors.initials: WW
authors.lastname: Xing
authors.affiliation: College of Horticulture, Nanjing Agricultural University, Key Laboratory of Southern Vegetables Genetic Improvement of Ministry of Agriculture, Nanjing 210095, PR China. Electronic address: 1136431291@qq.com.
authors.forename: Lin
authors.initials: L
authors.lastname: Li
authors.affiliation: College of Horticulture, Nanjing Agricultural University, Key Laboratory of Southern Vegetables Genetic Improvement of Ministry of Agriculture, Nanjing 210095, PR China. Electronic address: 2011104058@njau.edu.cn.
authors.forename: Pan
authors.initials: P
authors.lastname: Gao
authors.affiliation: College of Horticulture, Nanjing Agricultural University, Key Laboratory of Southern Vegetables Genetic Improvement of Ministry of Agriculture, Nanjing 210095, PR China. Electronic address: 2012804143@njau.edu.cn.
authors.forename: He
authors.initials: H
authors.lastname: Li
authors.affiliation: College of Horticulture, Nanjing Agricultural University, Key Laboratory of Southern Vegetables Genetic Improvement of Ministry of Agriculture, Nanjing 210095, PR China. Electronic address: 2012104050@njau.edu.cn.
authors.forename: Qiao-sai
authors.initials: QS
authors.lastname: Shao
authors.affiliation: College of Horticulture, Nanjing Agricultural University, Key Laboratory of Southern Vegetables Genetic Improvement of Ministry of Agriculture, Nanjing 210095, PR China. Electronic address: shusheng@njau.edu.cn.
authors.forename: Sheng
authors.initials: S
authors.lastname: Shu
authors.affiliation: College of Horticulture, Nanjing Agricultural University, Key Laboratory of Southern Vegetables Genetic Improvement of Ministry of Agriculture, Nanjing 210095, PR China; Facility Horticulture Institute, Nanjing Agricultural University, Suqian 223800, Jiangsu Province, PR China. Electronic address: jinsun@njau.edu.cn.
authors.forename: Jin
authors.initials: J
authors.lastname: Sun
authors.affiliation: College of Horticulture, Nanjing Agricultural University, Key Laboratory of Southern Vegetables Genetic Improvement of Ministry of Agriculture, Nanjing 210095, PR China; Facility Horticulture Institute, Nanjing Agricultural University, Suqian 223800, Jiangsu Province, PR China. Electronic address: srguo@njau.edu.cn.
authors.forename: Shi-rong
authors.initials: SR
authors.lastname: Guo
mesh_terms: D017610:Calcium Compounds / Q000494:pharmacology*; D050260:Carbohydrate Metabolism / Q000187:drug effects*; D028464:Cucurbita / Q000737:chemistry*; D009566:Nitrates / Q000494:pharmacology*; D018517:Plant Roots / Q000737:chemistry*; D036226:Seedlings / Q000378:metabolism*; D013312:Stress, Physiological / Q000187:drug effects*
chemical_list: D017610:Calcium Compounds; D009566:Nitrates; C059948:calcium nitrate
keywords: Ca(NO(3))(2) stress; Carbohydrate metabolism; Cucumber; Rootstock grafting; Transcript