A total of nine soybean (Glycine max (L.) Merr.) cultivars were divided into three yield levels which were planted under the same environmental condition. The net photosynthetic rate was measured by LI-6400 portab...A total of nine soybean (Glycine max (L.) Merr.) cultivars were divided into three yield levels which were planted under the same environmental condition. The net photosynthetic rate was measured by LI-6400 portable photosynthesis system. The chlorophyll content and specific leaf weight were measured with regular methods. The results showed that the specific leaf weight, chlorophyll content and net photosynthetic rate of high yield varieties were higher than those of low yield varieties. The yield had a significantly positive correlation with the net photosynthetic rate. With the improvement of modem technology, the net photosynthetic rate could be measured quickly and exactly. Hence, net photosynthetic rate could be used as an effective index in the selection of high yield soybean.展开更多
Increasing leaf photosynthesis per area(A) is of great importance to achieve yield further improvement. The aim of this study was to exploit varietal difference in A and its correlation with specific leaf weight(SL...Increasing leaf photosynthesis per area(A) is of great importance to achieve yield further improvement. The aim of this study was to exploit varietal difference in A and its correlation with specific leaf weight(SLW). Twelve rice cultivars, including 6 indica and 6 japonica varieties, were pot-grown under two N treatments, low N(LN) and sufficient N(SN). Leaf photosynthesis and related parameters were measured at tillering stage. Compared with LN treatment, A, stomatal conductance(g_s), mesophyll conductance(g_m), leaf N content(N_(area)), and chlorophyll content were significantly improved under SN treatment, while SLW and photosynthetic N use efficiency(PNUE) were generally decreased. Varietal difference in A was positively related to both g_s and g_m, but not related to N_(area). This resulted in a low PNUE in high N_(area) leaves. Varietal difference in PNUE was generally negatively related to SLW. Response of PNUE to N supply varied among different rice cultivars, and interestingly, the decrease in PNUE under SN was negatively related to the decrease in SLW. With a higher N_(area), japonica rice cultivars did not show a higher A than indica rice cultivars because of possession of high-SLW leaves. Therefore, varietal difference in A was not related to N_(area), and SLW can substantially interfere with the correlation between A and N_(area). These findings may provide useful information for rice breeders to maximize A and PNUE, rather than over reliance on N_(area) as an indicator of photosynthetic performance.展开更多
Faced with the scarcity of water resources and irrational fertilizer use,it is critical to supply plants with water and fertilizer in a coordinated pattern to improve yield with high water use efficiency(WUE).One such...Faced with the scarcity of water resources and irrational fertilizer use,it is critical to supply plants with water and fertilizer in a coordinated pattern to improve yield with high water use efficiency(WUE).One such method,alternate partial root-zone irrigation(APRI),has been practiced worldwide,but there is limited information on the performance of different irrigation regimes and nitrogen(N)rates under APRI.The objectives of this study were to investigate the effects of varying irrigation regimes and N rates on shoot growth,grain yield and WUE of maize(Zea mays L.)grown under APRI in the Hexi Corridor area of Northwest China in 2014 and 2015.The three N rates were 100,200 and 300 kg N ha–1,designated N1,N2 and N3,respectively.The three irrigation regimes of 45–50%,60–65%and 75–80%field capacity(FC)throughout the maize growing season,designated W1,W2 and W3,respectively,were applied in combination with each N rate.The results showed that W2 and W3 significantly increased the plant height,stem diameter,crop growth rate,chlorophyll SPAD value,net photosynthetic rate(Pn),biomass,grain yield,ears per ha,kernels per cob,1000-kernel weight,harvest index,evapotranspiration and leaf area index(LAI)compared to W1 at each N rate.The N2 and N3 treatments increased those parameters compared to N1 in each irrigation treatment.Increasing the N rate from the N2 to N3 resulted in increased biomass and grain yield under W3 while it had no impact on those under the W1 and W2 treatments.The W3 N3 and W2 N2 and W2 N3 treatments achieved the greatest and the second-greatest biomass and grain yield,respectively.Increasing the N rate significantly enhanced the maximum LAI(LAI at the silking stage)and Pn under W3,suggesting that the interaction of irrigation and fertilizer N management can effectively improve leaf growth and development,and consequently provide high biomass and grain yield of maize.The W2 N2,W2 N3 and W3 N3 treatments attained the greatest WUE among all the treatments.Thus,either 60–65%FC coupled with 200–300 kg N ha–1 or 75–80%FC coupled with 300 kg N ha–1 is proposed as a better pattern of irrigation and nitrogen application with positive regulative effects on grain yield and WUE of maize under APRI in the Hexi Corridor area of Northwest China and other regions with similar environments.These results can provide a basis for indepth understanding of the mechanisms of grain yield and WUE to supply levels of water and nitrogen.展开更多
Aims Ecological systems,especially soils,have been recently recognized as an important source of atmospheric nitric oxide(No).However,the study on the contribution of plants to atmospheric No budget is significantly l...Aims Ecological systems,especially soils,have been recently recognized as an important source of atmospheric nitric oxide(No).However,the study on the contribution of plants to atmospheric No budget is significantly lagged.The specific objectives of this study are to reveal the phylogenetic variation in No emission potential existing in various plant species and find out the possible leaf traits affecting No emission potential.Methods We measured No emission potential,leaf N and C content,C:N ratio,specific leaf area,net photosynthetic rate(Pn)and estimated photosynthetic N use efficiency(PNuE)of 88 plant species.Further investigation of the relationships between No emission potential and leaf traits were performed by simple linear regression analysis and pair-wise correlation coefficients analysis.Important Findingsmajor results are as follows:(1)No emission from plant species exhibited large variations,ranging from 0 to 41.7 nmol m^(−2) h^(−1),and the species frequency distributions of No emission potential could be fitted to a log-normal curve.(2)among 88 species,No emission potential was the highest in Podocarpus macrophyllus,but lowest in Zanthoxylum nitidum and Vernicia montana.(3)No emission potential has strong correlation to leaf N content,Pn and PNuE.The variations in No emission potential among diverse plant species may be closely related to leaf N level and net photosynthetic ability.展开更多
common maize synthetic rate( Photosynthetic characteristics were probed by sweet maize, waxy maize, high starch maize and The results revealed that leaf area index (LAI), chlorophyll a content, chlorophyll b cont...common maize synthetic rate( Photosynthetic characteristics were probed by sweet maize, waxy maize, high starch maize and The results revealed that leaf area index (LAI), chlorophyll a content, chlorophyll b content,photo-PR) showed single peak curve at the whole growth stage. The stages of peak were different according to different varieties. NEAUS4 had the lowest peak and while SIDAN 19 had the highest among all stages. Ratio of chlorophyll a to b was low at seedling stage, reached the peak atjointing stage and then declined. SIDAN 19 had the lower level at the last stages.展开更多
明确吉林省不同年代玉米品种产量、叶片氮含量与光合特性对不同氮素用量的响应趋势,对东北地区玉米高产品种选育具有重要的实践意义。本研究以20世纪70年代年以来吉林省大面积推广应用的6个代表性品种为研究对象(1970s:吉单101、中单2号...明确吉林省不同年代玉米品种产量、叶片氮含量与光合特性对不同氮素用量的响应趋势,对东北地区玉米高产品种选育具有重要的实践意义。本研究以20世纪70年代年以来吉林省大面积推广应用的6个代表性品种为研究对象(1970s:吉单101、中单2号;1990s:四单19、吉单159;2010s:先玉335和农华101),在大田条件下共设置4个氮素水平(0、125、250和375 kg hm^(–2)),分析了氮素施用量对不同年代玉米品种产量、叶片氮含量及光合特征参数等的影响。结果表明,所有氮水平下玉米籽粒产量均随品种更替而提高,现代品种在较高氮水平下(≥250 kg hm^(–2))产量优势更明显,各处理产量的提高主要是单穗粒数和粒重同时增加的结果。当施氮量不高于250 kg hm^(–2)时,各年代玉米品种穗位叶净光合速率(Pn)均随施氮量增加而提高,现代品种显著高于老品种,当施氮量为375kghm^(–2)时Pn均显著降低,降低幅度表现为老品种高于现代品种。而吐丝至蜡熟期,Pn降低幅度随施氮量增加和品种更替而减小。玉米光补偿点、暗呼吸速率在不同时期均表现为2010s最高、1990s次之、1970s最低,其中2010s品种的光补偿点比1990s、1970s品种平均分别提高9.72%、27.84%,暗呼吸速率平均提高7.82%、32.98%。各年代品种比叶重(specific leafweight,SLW)随施氮量增加而提高,同一施氮量下SLW表现为随品种更替而降低。不同品种叶片单位面积氮含量(Narea)均随施氮量增加而提高,不施氮处理老品种显著降低,施氮处理品种间无显著差异。相关分析表明,Pn与SLW呈显著正相关关系,而Pn与Narea之间关系可用二次曲线方程拟合,Pn随Narea增加出现转折的Narea值为1.57g m–2。不同年代品种的光合氮利用效率(PNUE)均随施氮量增加而降低,而较高氮水平下(≥250 kg hm^(–2))PNUE随品种更替而显著提高。综上,在较高氮水平下现代玉米品种比老品种显著增产主要归因于其Pn和PNUE的提高,而Pn和PNUE的提高又与比叶重(SLM)、叶片N含量(Nmass、Narea)等性状密切相关,推荐在玉米品种选育过程中参考。展开更多
Variations in plant traits are indicative of plant adaptations to forest environments,and studying their relationships with tree growth provides valuable insights into forest regeneration.The spatial arrangement of pl...Variations in plant traits are indicative of plant adaptations to forest environments,and studying their relationships with tree growth provides valuable insights into forest regeneration.The spatial arrangement of plant seeds within the forest litter or soil critically infuences the variations of root-leaf traits,thereby affecting the adaptive strategies of emerging seedlings.However,our current understanding of the impacts of individual root-leaf traits on seedling growth in different relative position,and whether these traits together affect growth,remains limited.This study focuses on the dominant tree species,Castanopsis kawakamii,within the Sanming C.kawakamii Nature Reserve of China.The present experiment aimed to examine the variations in root-leaf traits of seedling,focus on the relative positions of seeds within different layers:beneath or above the litter layer,or within the bare soil layer(without litter).Our fndings provided evidence supporting a coordinated relationship between root and leaf traits,wherein leaf traits varied in conjunction with root traits in the relative positions of seeds.Specifcally,we observed that seedlings exhibited higher values for specifc leaf area and average root diameter,while displaying lower root tissue density.The mixed model explained 86.1%of the variation in root-leaf traits,surpassing the variation explained by the relative positions.Furthermore,soil nitrogen acted as a mediator,regulating the relationship between seedling growth and root-leaf traits,specifcally leaf dry matter content and root tissue density.Therefore,future studies should consider artifcially manipulating tree species diversity based on root-leaf traits characteristics to promote forest recovery.展开更多
基金Supported by the National Natural Science Foundation of China (30871547)Foundation of Department of Education of Jilin Province (2006041)Scientific Research Foundation of Jilin Agricultural University (2009028)
文摘A total of nine soybean (Glycine max (L.) Merr.) cultivars were divided into three yield levels which were planted under the same environmental condition. The net photosynthetic rate was measured by LI-6400 portable photosynthesis system. The chlorophyll content and specific leaf weight were measured with regular methods. The results showed that the specific leaf weight, chlorophyll content and net photosynthetic rate of high yield varieties were higher than those of low yield varieties. The yield had a significantly positive correlation with the net photosynthetic rate. With the improvement of modem technology, the net photosynthetic rate could be measured quickly and exactly. Hence, net photosynthetic rate could be used as an effective index in the selection of high yield soybean.
基金supported by the National Natural Science Foundation of China(31301840)the National Excellent Doctoral Dissertation of China(201465)+2 种基金the Program for Changjiang Scholars and Innovative Research Team in University of China(IRT1247)the Natural Science Foundation of Hubei Province,China(2013CFB201)the Fundamental Research Funds for the Central Universities,China(2013PY107)
文摘Increasing leaf photosynthesis per area(A) is of great importance to achieve yield further improvement. The aim of this study was to exploit varietal difference in A and its correlation with specific leaf weight(SLW). Twelve rice cultivars, including 6 indica and 6 japonica varieties, were pot-grown under two N treatments, low N(LN) and sufficient N(SN). Leaf photosynthesis and related parameters were measured at tillering stage. Compared with LN treatment, A, stomatal conductance(g_s), mesophyll conductance(g_m), leaf N content(N_(area)), and chlorophyll content were significantly improved under SN treatment, while SLW and photosynthetic N use efficiency(PNUE) were generally decreased. Varietal difference in A was positively related to both g_s and g_m, but not related to N_(area). This resulted in a low PNUE in high N_(area) leaves. Varietal difference in PNUE was generally negatively related to SLW. Response of PNUE to N supply varied among different rice cultivars, and interestingly, the decrease in PNUE under SN was negatively related to the decrease in SLW. With a higher N_(area), japonica rice cultivars did not show a higher A than indica rice cultivars because of possession of high-SLW leaves. Therefore, varietal difference in A was not related to N_(area), and SLW can substantially interfere with the correlation between A and N_(area). These findings may provide useful information for rice breeders to maximize A and PNUE, rather than over reliance on N_(area) as an indicator of photosynthetic performance.
基金The study was funded by the National Natural Science Foundation of China(51809006 and 51079124).
文摘Faced with the scarcity of water resources and irrational fertilizer use,it is critical to supply plants with water and fertilizer in a coordinated pattern to improve yield with high water use efficiency(WUE).One such method,alternate partial root-zone irrigation(APRI),has been practiced worldwide,but there is limited information on the performance of different irrigation regimes and nitrogen(N)rates under APRI.The objectives of this study were to investigate the effects of varying irrigation regimes and N rates on shoot growth,grain yield and WUE of maize(Zea mays L.)grown under APRI in the Hexi Corridor area of Northwest China in 2014 and 2015.The three N rates were 100,200 and 300 kg N ha–1,designated N1,N2 and N3,respectively.The three irrigation regimes of 45–50%,60–65%and 75–80%field capacity(FC)throughout the maize growing season,designated W1,W2 and W3,respectively,were applied in combination with each N rate.The results showed that W2 and W3 significantly increased the plant height,stem diameter,crop growth rate,chlorophyll SPAD value,net photosynthetic rate(Pn),biomass,grain yield,ears per ha,kernels per cob,1000-kernel weight,harvest index,evapotranspiration and leaf area index(LAI)compared to W1 at each N rate.The N2 and N3 treatments increased those parameters compared to N1 in each irrigation treatment.Increasing the N rate from the N2 to N3 resulted in increased biomass and grain yield under W3 while it had no impact on those under the W1 and W2 treatments.The W3 N3 and W2 N2 and W2 N3 treatments achieved the greatest and the second-greatest biomass and grain yield,respectively.Increasing the N rate significantly enhanced the maximum LAI(LAI at the silking stage)and Pn under W3,suggesting that the interaction of irrigation and fertilizer N management can effectively improve leaf growth and development,and consequently provide high biomass and grain yield of maize.The W2 N2,W2 N3 and W3 N3 treatments attained the greatest WUE among all the treatments.Thus,either 60–65%FC coupled with 200–300 kg N ha–1 or 75–80%FC coupled with 300 kg N ha–1 is proposed as a better pattern of irrigation and nitrogen application with positive regulative effects on grain yield and WUE of maize under APRI in the Hexi Corridor area of Northwest China and other regions with similar environments.These results can provide a basis for indepth understanding of the mechanisms of grain yield and WUE to supply levels of water and nitrogen.
基金This study was financially supported by the Natural Science Foundation of China(NSFC)(31300505,31260057,30930076,30670317)Research Fund of State Key Laboratory of Soil and Sustainable Agriculture,Nanjing Institute of Soil Science,Chinese Academy of Science(Y412201449)+1 种基金China Postdoctoral Science Foundation(2012M521278)the Scholarship Award for Excellent Doctoral Student granted by the Chinese Ministry of Education.
文摘Aims Ecological systems,especially soils,have been recently recognized as an important source of atmospheric nitric oxide(No).However,the study on the contribution of plants to atmospheric No budget is significantly lagged.The specific objectives of this study are to reveal the phylogenetic variation in No emission potential existing in various plant species and find out the possible leaf traits affecting No emission potential.Methods We measured No emission potential,leaf N and C content,C:N ratio,specific leaf area,net photosynthetic rate(Pn)and estimated photosynthetic N use efficiency(PNuE)of 88 plant species.Further investigation of the relationships between No emission potential and leaf traits were performed by simple linear regression analysis and pair-wise correlation coefficients analysis.Important Findingsmajor results are as follows:(1)No emission from plant species exhibited large variations,ranging from 0 to 41.7 nmol m^(−2) h^(−1),and the species frequency distributions of No emission potential could be fitted to a log-normal curve.(2)among 88 species,No emission potential was the highest in Podocarpus macrophyllus,but lowest in Zanthoxylum nitidum and Vernicia montana.(3)No emission potential has strong correlation to leaf N content,Pn and PNuE.The variations in No emission potential among diverse plant species may be closely related to leaf N level and net photosynthetic ability.
文摘common maize synthetic rate( Photosynthetic characteristics were probed by sweet maize, waxy maize, high starch maize and The results revealed that leaf area index (LAI), chlorophyll a content, chlorophyll b content,photo-PR) showed single peak curve at the whole growth stage. The stages of peak were different according to different varieties. NEAUS4 had the lowest peak and while SIDAN 19 had the highest among all stages. Ratio of chlorophyll a to b was low at seedling stage, reached the peak atjointing stage and then declined. SIDAN 19 had the lower level at the last stages.
文摘明确吉林省不同年代玉米品种产量、叶片氮含量与光合特性对不同氮素用量的响应趋势,对东北地区玉米高产品种选育具有重要的实践意义。本研究以20世纪70年代年以来吉林省大面积推广应用的6个代表性品种为研究对象(1970s:吉单101、中单2号;1990s:四单19、吉单159;2010s:先玉335和农华101),在大田条件下共设置4个氮素水平(0、125、250和375 kg hm^(–2)),分析了氮素施用量对不同年代玉米品种产量、叶片氮含量及光合特征参数等的影响。结果表明,所有氮水平下玉米籽粒产量均随品种更替而提高,现代品种在较高氮水平下(≥250 kg hm^(–2))产量优势更明显,各处理产量的提高主要是单穗粒数和粒重同时增加的结果。当施氮量不高于250 kg hm^(–2)时,各年代玉米品种穗位叶净光合速率(Pn)均随施氮量增加而提高,现代品种显著高于老品种,当施氮量为375kghm^(–2)时Pn均显著降低,降低幅度表现为老品种高于现代品种。而吐丝至蜡熟期,Pn降低幅度随施氮量增加和品种更替而减小。玉米光补偿点、暗呼吸速率在不同时期均表现为2010s最高、1990s次之、1970s最低,其中2010s品种的光补偿点比1990s、1970s品种平均分别提高9.72%、27.84%,暗呼吸速率平均提高7.82%、32.98%。各年代品种比叶重(specific leafweight,SLW)随施氮量增加而提高,同一施氮量下SLW表现为随品种更替而降低。不同品种叶片单位面积氮含量(Narea)均随施氮量增加而提高,不施氮处理老品种显著降低,施氮处理品种间无显著差异。相关分析表明,Pn与SLW呈显著正相关关系,而Pn与Narea之间关系可用二次曲线方程拟合,Pn随Narea增加出现转折的Narea值为1.57g m–2。不同年代品种的光合氮利用效率(PNUE)均随施氮量增加而降低,而较高氮水平下(≥250 kg hm^(–2))PNUE随品种更替而显著提高。综上,在较高氮水平下现代玉米品种比老品种显著增产主要归因于其Pn和PNUE的提高,而Pn和PNUE的提高又与比叶重(SLM)、叶片N含量(Nmass、Narea)等性状密切相关,推荐在玉米品种选育过程中参考。
基金sponsored by National Natural Science Foundation of China(NSFC)(31700550,31770678)Fujian Province Forestry and Technology Project of China(2022FKJ21)Forestry Peak Discipline Construction Project of Fujian Agriculture and Forestry University of China(72202200205).
文摘Variations in plant traits are indicative of plant adaptations to forest environments,and studying their relationships with tree growth provides valuable insights into forest regeneration.The spatial arrangement of plant seeds within the forest litter or soil critically infuences the variations of root-leaf traits,thereby affecting the adaptive strategies of emerging seedlings.However,our current understanding of the impacts of individual root-leaf traits on seedling growth in different relative position,and whether these traits together affect growth,remains limited.This study focuses on the dominant tree species,Castanopsis kawakamii,within the Sanming C.kawakamii Nature Reserve of China.The present experiment aimed to examine the variations in root-leaf traits of seedling,focus on the relative positions of seeds within different layers:beneath or above the litter layer,or within the bare soil layer(without litter).Our fndings provided evidence supporting a coordinated relationship between root and leaf traits,wherein leaf traits varied in conjunction with root traits in the relative positions of seeds.Specifcally,we observed that seedlings exhibited higher values for specifc leaf area and average root diameter,while displaying lower root tissue density.The mixed model explained 86.1%of the variation in root-leaf traits,surpassing the variation explained by the relative positions.Furthermore,soil nitrogen acted as a mediator,regulating the relationship between seedling growth and root-leaf traits,specifcally leaf dry matter content and root tissue density.Therefore,future studies should consider artifcially manipulating tree species diversity based on root-leaf traits characteristics to promote forest recovery.