By pot experiment under artificially simulated water stress conditions, soluble protein content, MDA content and SOD, POD, CAT and APX activities in Malus sieversfi leaves were determined to reveal the response mechan...By pot experiment under artificially simulated water stress conditions, soluble protein content, MDA content and SOD, POD, CAT and APX activities in Malus sieversfi leaves were determined to reveal the response mechanism of M. sieversii to changes of relative soil water content. According to the results, with the decrease of relative soil water content, MDA content in M. sieversii leaves increased by mem- brane lipid peroxidation. Cells resist water stress-induced membrane lipid peroxidation and clear the increased reactive oxygen species by improving soluble protein content and SOD, POD, CAT and APX activities. However, various enzymes were involved in the response to water stress under different moisture conditions. In addition, the results indicated that M. sieversii had a good adaptability to higher relative soil water contents.展开更多
The authors tested the contents of ABA (abscisic acid), ZR (zeatin riboside), DHZR (dihydrozeatin riboside) and iPA (isopentenyl adenosine) in leafless and leafy apple trees (\%Red Fuji/Malus micromalus Makino\%) duri...The authors tested the contents of ABA (abscisic acid), ZR (zeatin riboside), DHZR (dihydrozeatin riboside) and iPA (isopentenyl adenosine) in leafless and leafy apple trees (\%Red Fuji/Malus micromalus Makino\%) during soil drought stress. ABA concentration in drought stressed leafless trees increased significantly compared to the controls. ABA both in roots and xylem rose steadily in the earlier drought stage, reaching a maximum of 1.46±0.35 nmol g\+\{ 1\}FW and 117 nmol l\+\{-1\} after the 8th day. Similar change patterns of ABA concentration was observed in the leafy trees during soil drought stress; ABA concentrations in roots and xylem sap increased and reached the maximum in the first three days; after 8th day , it decreased slightly, whereas leaf ABA concentration increased steadily in drought stressed plants throughout the duration of the experiment. Between drought stressed and control trees, no significant differences were observed in concentration of ZR and DHZR in both leafless and leafy trees; whereas iPA concentration of the drought stressed leafless and leafy plants decreased markedly in the later stage of drought. These results showed that endogenous ABA originated mainly from the roots in the earlier drought stage, and mainly from the leaves in the later drought stage. Total CTK showed no reduction in the earlier drought stage and decreased in the later drought stage.展开更多
在池栽条件下,研究了施氮量和花后土壤相对含水量对小麦氮代谢特性和子粒蛋白质含量的影响。结果表明,在同一施氮量下,旗叶和子粒硝酸还原酶(NR)和谷氨酰胺合成酶(GS)活性表现为花后土壤相对含水量(Soil relative water content,SRWC)在...在池栽条件下,研究了施氮量和花后土壤相对含水量对小麦氮代谢特性和子粒蛋白质含量的影响。结果表明,在同一施氮量下,旗叶和子粒硝酸还原酶(NR)和谷氨酰胺合成酶(GS)活性表现为花后土壤相对含水量(Soil relative water content,SRWC)在60%～70%时最高,过低(40%～50%)或过高(80%--90%)均降低NR和GS活性。旗叶蛋白酶活性随土壤相对含水量增加而降低;花后土壤相对含水量过低不利于叶片游离氨基酸含量的提高,过高则前期氨基酸合成少,后期向子粒转运不彻底。子粒游离氨基酸和蛋白质含量也随土壤相对含水量增加而降低;子粒蛋白质积累量以花后土壤相对含水量为60%～70%时最高,过高和过低均不利于子粒蛋白质积累。在同一土壤含水量下,旗叶和子粒NR和GS活性表现为随着施氮量的增加而升高,蛋白酶活性随着施氮量增加而降低;旗叶和子粒游离氨基酸含量、子粒蛋白质含量和积累量随施氮量增加而提高,但施氮量过多。蛋白质积累量增加幅度减小。试验表明,小麦生产中可以通过施用氮肥和控制花后土壤水分含量技术,调节植株氮代谢,提高子粒蛋白质含量。展开更多
Negative soil water balance （i.e., water input 〈 water output） can lead to soil desiccation and subsequently the occurrence of a dried soil layer （DSL）. The DSLs are generally studied at a specific sampling depth...Negative soil water balance （i.e., water input 〈 water output） can lead to soil desiccation and subsequently the occurrence of a dried soil layer （DSL）. The DSLs are generally studied at a specific sampling depth （e.g., 500 cm）, and the actual extent of DSLs remains unknown due to the challenge of collecting deep soil samples. To investigate the characteristics of actual DSLs under different ages of apple orchards and ascertain the optimal age of apple orchards for avoiding/controlling the formation of DSLs, soil samples were collected to a depth of 1800 cm under apple orchards of different ages in Changwu on the Loess Plateau of China. As the ages increased, soil water content （SWC） and mean SWC in DSLs showed an overall decreasing trend, whereas while DSL thickness and the quantity of water deficit （QWD） in DSLs demonstrated an increasing trend. The DSL was the thickest （1 600 cm） under the 17-yeax-old orchard, the forming velocity of DSL thickness was the highest at the apple tree growth stage of 9-17 years （168 cm year-l）, and the highest increasing velocity of QWD （-181 mm year-1） was also observed at this stage. The thickness of DSL was significantly correlated with growth age and root depth of apple trees （r 〉 0.88）, whereas the QWD and mean SWC in DSLs were found to have no correlation with them. The optimal age of apple orchards for avoiding/controlling the formation of DSLs was about 9 years. This information provided pertinent references for the management of deep water resources by controlling the growth age of plants. Key Words： deep soil, growth age, plant roots, soil desiccation, soil water content, soil-plant water relation.展开更多
基金Supported by Science and Technology Innovation Project of Ji'nan City "Identification of Stress-resistant Malus sieversii Germplasm Resources and Screening of Stressresistance Functional Genes"(201401125)~~
文摘By pot experiment under artificially simulated water stress conditions, soluble protein content, MDA content and SOD, POD, CAT and APX activities in Malus sieversfi leaves were determined to reveal the response mechanism of M. sieversii to changes of relative soil water content. According to the results, with the decrease of relative soil water content, MDA content in M. sieversii leaves increased by mem- brane lipid peroxidation. Cells resist water stress-induced membrane lipid peroxidation and clear the increased reactive oxygen species by improving soluble protein content and SOD, POD, CAT and APX activities. However, various enzymes were involved in the response to water stress under different moisture conditions. In addition, the results indicated that M. sieversii had a good adaptability to higher relative soil water contents.
文摘The authors tested the contents of ABA (abscisic acid), ZR (zeatin riboside), DHZR (dihydrozeatin riboside) and iPA (isopentenyl adenosine) in leafless and leafy apple trees (\%Red Fuji/Malus micromalus Makino\%) during soil drought stress. ABA concentration in drought stressed leafless trees increased significantly compared to the controls. ABA both in roots and xylem rose steadily in the earlier drought stage, reaching a maximum of 1.46±0.35 nmol g\+\{ 1\}FW and 117 nmol l\+\{-1\} after the 8th day. Similar change patterns of ABA concentration was observed in the leafy trees during soil drought stress; ABA concentrations in roots and xylem sap increased and reached the maximum in the first three days; after 8th day , it decreased slightly, whereas leaf ABA concentration increased steadily in drought stressed plants throughout the duration of the experiment. Between drought stressed and control trees, no significant differences were observed in concentration of ZR and DHZR in both leafless and leafy trees; whereas iPA concentration of the drought stressed leafless and leafy plants decreased markedly in the later stage of drought. These results showed that endogenous ABA originated mainly from the roots in the earlier drought stage, and mainly from the leaves in the later drought stage. Total CTK showed no reduction in the earlier drought stage and decreased in the later drought stage.
文摘在池栽条件下,研究了施氮量和花后土壤相对含水量对小麦氮代谢特性和子粒蛋白质含量的影响。结果表明,在同一施氮量下,旗叶和子粒硝酸还原酶(NR)和谷氨酰胺合成酶(GS)活性表现为花后土壤相对含水量(Soil relative water content,SRWC)在60%～70%时最高,过低(40%～50%)或过高(80%--90%)均降低NR和GS活性。旗叶蛋白酶活性随土壤相对含水量增加而降低;花后土壤相对含水量过低不利于叶片游离氨基酸含量的提高,过高则前期氨基酸合成少,后期向子粒转运不彻底。子粒游离氨基酸和蛋白质含量也随土壤相对含水量增加而降低;子粒蛋白质积累量以花后土壤相对含水量为60%～70%时最高,过高和过低均不利于子粒蛋白质积累。在同一土壤含水量下,旗叶和子粒NR和GS活性表现为随着施氮量的增加而升高,蛋白酶活性随着施氮量增加而降低;旗叶和子粒游离氨基酸含量、子粒蛋白质含量和积累量随施氮量增加而提高,但施氮量过多。蛋白质积累量增加幅度减小。试验表明,小麦生产中可以通过施用氮肥和控制花后土壤水分含量技术,调节植株氮代谢,提高子粒蛋白质含量。
基金supported by the National Natural Science Foundation of China (No. 41471189)the Youth Science and Technology New Star Foundation of Shaanxi Province, China (No. 2013KJXX-09)+1 种基金the CAS "Light of West China" Programthe Youth Innovation Promotion Association CAS
文摘Negative soil water balance （i.e., water input 〈 water output） can lead to soil desiccation and subsequently the occurrence of a dried soil layer （DSL）. The DSLs are generally studied at a specific sampling depth （e.g., 500 cm）, and the actual extent of DSLs remains unknown due to the challenge of collecting deep soil samples. To investigate the characteristics of actual DSLs under different ages of apple orchards and ascertain the optimal age of apple orchards for avoiding/controlling the formation of DSLs, soil samples were collected to a depth of 1800 cm under apple orchards of different ages in Changwu on the Loess Plateau of China. As the ages increased, soil water content （SWC） and mean SWC in DSLs showed an overall decreasing trend, whereas while DSL thickness and the quantity of water deficit （QWD） in DSLs demonstrated an increasing trend. The DSL was the thickest （1 600 cm） under the 17-yeax-old orchard, the forming velocity of DSL thickness was the highest at the apple tree growth stage of 9-17 years （168 cm year-l）, and the highest increasing velocity of QWD （-181 mm year-1） was also observed at this stage. The thickness of DSL was significantly correlated with growth age and root depth of apple trees （r 〉 0.88）, whereas the QWD and mean SWC in DSLs were found to have no correlation with them. The optimal age of apple orchards for avoiding/controlling the formation of DSLs was about 9 years. This information provided pertinent references for the management of deep water resources by controlling the growth age of plants. Key Words： deep soil, growth age, plant roots, soil desiccation, soil water content, soil-plant water relation.
