磷是植物必需营养元素之一,以多种方式影响作物氮吸收、利用。花生属于豆科作物,氮素营养来源包括土壤、肥料和根瘤固氮。本研究以山东省主推品种花育22号(大花生)和花育20号(小花生)为材料,设置5个施磷(P2O5)水平(0、45、90、135和180 ...磷是植物必需营养元素之一,以多种方式影响作物氮吸收、利用。花生属于豆科作物,氮素营养来源包括土壤、肥料和根瘤固氮。本研究以山东省主推品种花育22号(大花生)和花育20号(小花生)为材料,设置5个施磷(P2O5)水平(0、45、90、135和180 kg hm^-2),利用15N示踪技术,进行了2年桶栽试验。结果表明,施磷提高了两花生品种肥料氮、土壤氮及根瘤固氮积累量,其中根瘤固氮积累量的增幅大于土壤氮和肥料氮,年份和品种间表现基本一致;随施磷量增加,根瘤数量、鲜重及根瘤固氮积累比例呈增加趋势,土壤氮、肥料氮积累比例呈降低趋势;施磷量在45~90 kg hm^-2范围内,氮肥利用效率、荚果氮素利用效率及产量均呈增加趋势,施磷量超过90 kg hm 2,上述三指标呈降低趋势或不再增加;磷肥农学效率随施磷量增加而降低;根瘤固氮积累量与荚果产量、植株全氮积累量呈极显著正相关,与土壤氮、肥料氮积累比例及氮素荚果利用效率呈极显著负相关。根瘤固氮积累比例与土壤氮和肥料氮积累量、供氮比例及氮肥利用率呈极显著负相关。综上,施磷能增加花生根瘤固氮供氮量及供氮比例,降低对肥料氮和土壤氮的依赖,但过量施磷不利于氮、磷效率和产量的提高。45~90 kg hm^-2(P2O5)为花生适宜施磷量。展开更多
为明确花生单粒精播适宜的氮肥水平和种植密度,本研究于2018年和2019年以‘花育22’为供试花生品种,设置3个氮肥水平(0 kg hm^-2,N0;60 kg hm^-2,N1;120 kg hm^-2,N2),3个种植密度(7.93万株hm^-2,D1;15.86万株hm^-2,D2;23.79万株hm^-2,D...为明确花生单粒精播适宜的氮肥水平和种植密度,本研究于2018年和2019年以‘花育22’为供试花生品种,设置3个氮肥水平(0 kg hm^-2,N0;60 kg hm^-2,N1;120 kg hm^-2,N2),3个种植密度(7.93万株hm^-2,D1;15.86万株hm^-2,D2;23.79万株hm^-2,D3),采用二因素裂区试验设计,研究氮肥、密度及其互作对单粒精播花生根系形态、植株性状及产量的影响。氮肥对花生根长、根表面积、根体积、根干重的影响不显著,而密度的影响显著。单株根长、根表面积、根体积及根系干重随密度的增加而降低,D1显著高于D2和D3,D2、D3处理间差异不显著;单位面积根长、根表面积、根体积及根系干重随密度的增加而增加,D1显著低于D2和D3,D2、D3处理间差异不显著。氮肥和密度互作对2019年收获期单位面积根长、根表面积的影响显著,与D1相比,N1处理下D3的增幅显著高于N0和N2处理。氮肥及氮肥与密度互作对植株性状的影响存在年度和时期间的差异,主茎叶片数、侧枝数和主茎第一节间粗随密度增加有降低趋势。氮肥对荚果产量的影响不显著,荚果产量随密度的增加呈增加的趋势。产量与根体积、根干重、主茎叶片数、主茎高及侧枝长呈显著正相关。综上所述,在本试验条件下,花生单粒精播适宜的氮肥(N)水平为60 kg hm-2,种植密度为18.8万株hm-2。展开更多
施氮对豆科作物土壤固氮菌的影响机理尚不明确。深入研究施氮对花生土壤固氮菌的影响,对花生田高效施氮和农业可持续发展具有重要意义。本研究以结瘤(花育22)和不结瘤(BL)花生为材料,设置N0(不施氮,0 kg hm^(-2))、N60(减量施氮,60 kg h...施氮对豆科作物土壤固氮菌的影响机理尚不明确。深入研究施氮对花生土壤固氮菌的影响,对花生田高效施氮和农业可持续发展具有重要意义。本研究以结瘤(花育22)和不结瘤(BL)花生为材料,设置N0(不施氮,0 kg hm^(-2))、N60(减量施氮,60 kg hm^(-2))、N120(常量施氮,120 kg hm^(-2))和N180(过量施氮,180 kg hm^(-2))4个施氮水平,探讨不同施氮水平对不同结瘤特性花生土壤固氮菌的影响。采用实时荧光定量PCR和高通量测序技术,以nifH基因为标靶,分析土壤固氮菌丰度、多样性和群落组成。结果表明:(1)施氮显著提高土壤氮组分含量,N120结瘤花生土壤中微生物量氮和可溶性有机氮显著高于不结瘤花生。不结瘤花生荚果产量随施氮水平呈线性增加,而结瘤花生产量不受施氮影响。(2)施氮条件下,不结瘤花生土壤nifH拷贝数显著降低,而结瘤花生土壤nifH拷贝数随施氮水平增加先降低后增加。(3)施氮对不结瘤花生土壤固氮菌多样性先抑制后促进,而施氮对结瘤花生土壤固氮菌多样性呈先促进后抑制的模式,并在N120达到最大值。(4)施氮显著改变不结瘤花生土壤固氮菌群落组成,不同施氮水平优势属分别为nonrank_Bacteria(N0)、unclassified_Cyanobacteria(N60)、nonrank_Bacteria(N120)和Skermanella(N180),硝态氮是影响处理间土壤固氮菌群落组成差异的唯一显著因素;结瘤花生土壤各施氮水平固氮菌群落组成相似,除N120外,均以unclassified_Proteobacteria和Skermanella占优。不结瘤与结瘤花生土壤固氮菌对施氮水平截然不同的响应可能是由于二者分别受到不同氮源的影响(肥料氮vs.根瘤固氮)。本研究中120 kg hm^(-2)是对土壤固氮和花生生产最优的施氮水平。展开更多
Rational application of different forms of nitrogen（N） fertilizer for peanut（Arachis hypogaea L.） requires tracking the N supplied sources which are commonly not available in the differences among the three source...Rational application of different forms of nitrogen（N） fertilizer for peanut（Arachis hypogaea L.） requires tracking the N supplied sources which are commonly not available in the differences among the three sources：root nodule,soil and fertilizer.In this study,two kinds of peanut plants（nodulated variety（Huayu 22） and non-nodulated variety（NN-1）） were choosed and four kinds of N fertilizers：urea-N（CONH_2-N）,ammonium-N（NH_4~＋-N）,nitrate-N（NO_3^--N） and NH_4~＋ ＋NO_3^--N labeled by^（15）N isotope were applied in the field barrel experiment in Chengyang Experimental Station,Shandong Province,China,to determine the N supplied sources and N use efficiency over peanut growing stages.The results showed that intensities and amounts of N supply from the three sources were all higher at middle growing stages（pegging phase and podding phase）.The accumulated amounts of N supply from root nodule,soil and fertilizer over the growing stages were 8.3,5.3 and 3.8g m^（-2） in CONH_2-N treatment,which are all significantly higher than in the other three treatments.At seedling phase,soil supplied the most N for peanut growth,then root nodule controlled the N supply at pegging phase and podding phase,but soil mainly provided N again at the last stage（pod filling phase）.For the whole growing stages,root nodule supplied the most N（47.8 and 43.0%） in CONH_2-N and NH_4~＋-N treatments,whereas soil supplied the most N（41.7 and 40.9%） in NH_4~＋ ＋NO_3^--N and NO_3^--N treatments.The N use efficiency was higher at pegging phase and podding phase,while accumulated N use efficiency over the growing stages was higher in CONH_2-N treatment（42.2%） than in other three treatments（30.4%in NH_4~＋-N treatment,29.4%in NO_3^--N treatment,29.4%in NH_4~＋ ＋NO_3^--N treatment）.In peanut growing field,application of CONH_2-N is a better way to increase the supply of N from root nodule and improve the N use efficiency.展开更多
Electron structure of three series of alloy heterojunctions(GaAs)_(x)(Ge_(2))_(1-x)/Ge,(AlAs)_(x)(Ge2)_(1-x)/Ge and Al_(x)G_(1-x)As/Ge are calculated by linear muffin-tin orbital method with atomic-sphere approximatio...Electron structure of three series of alloy heterojunctions(GaAs)_(x)(Ge_(2))_(1-x)/Ge,(AlAs)_(x)(Ge2)_(1-x)/Ge and Al_(x)G_(1-x)As/Ge are calculated by linear muffin-tin orbital method with atomic-sphere approximation using the average-bond-energy theory in conjunction with a cluster expansion method.The results indicate the variations ofΔE_(v)(x)at heterojunctions(GeAs)_(x)(Ge2)_(1-x)/Ge and(AlAs)_(x)(Ge2)_(1-x)/Ge are nonlinear,which are very different from that of Al_(x)Ga_(1-x)As/Ge.展开更多
The electronic structure of InAs_(0.25)P_(0.75)/InP strained quantum wires grown on InP(001)oriented substrates is studied within the framework of effective-mass envelope-function theory.At theΓpoint,the electron and...The electronic structure of InAs_(0.25)P_(0.75)/InP strained quantum wires grown on InP(001)oriented substrates is studied within the framework of effective-mass envelope-function theory.At theΓpoint,the electron and valence subband energy levels with and without spin-split-off band,and the absorption spectra are calculated.The effects of strain and spin-split-off band on valence energy levels are presented.The results show that the uppermost valence subband is almost unaffected by the strain induced coupling between the heavy-and light-hole bands and the spin-split-off bands while the other subbands are more markedly affected in the InAs0.25P0.75/InP strained quantum wires.展开更多
文摘磷是植物必需营养元素之一,以多种方式影响作物氮吸收、利用。花生属于豆科作物,氮素营养来源包括土壤、肥料和根瘤固氮。本研究以山东省主推品种花育22号(大花生)和花育20号(小花生)为材料,设置5个施磷(P2O5)水平(0、45、90、135和180 kg hm^-2),利用15N示踪技术,进行了2年桶栽试验。结果表明,施磷提高了两花生品种肥料氮、土壤氮及根瘤固氮积累量,其中根瘤固氮积累量的增幅大于土壤氮和肥料氮,年份和品种间表现基本一致;随施磷量增加,根瘤数量、鲜重及根瘤固氮积累比例呈增加趋势,土壤氮、肥料氮积累比例呈降低趋势;施磷量在45~90 kg hm^-2范围内,氮肥利用效率、荚果氮素利用效率及产量均呈增加趋势,施磷量超过90 kg hm 2,上述三指标呈降低趋势或不再增加;磷肥农学效率随施磷量增加而降低;根瘤固氮积累量与荚果产量、植株全氮积累量呈极显著正相关,与土壤氮、肥料氮积累比例及氮素荚果利用效率呈极显著负相关。根瘤固氮积累比例与土壤氮和肥料氮积累量、供氮比例及氮肥利用率呈极显著负相关。综上,施磷能增加花生根瘤固氮供氮量及供氮比例,降低对肥料氮和土壤氮的依赖,但过量施磷不利于氮、磷效率和产量的提高。45~90 kg hm^-2(P2O5)为花生适宜施磷量。
文摘为明确花生单粒精播适宜的氮肥水平和种植密度,本研究于2018年和2019年以‘花育22’为供试花生品种,设置3个氮肥水平(0 kg hm^-2,N0;60 kg hm^-2,N1;120 kg hm^-2,N2),3个种植密度(7.93万株hm^-2,D1;15.86万株hm^-2,D2;23.79万株hm^-2,D3),采用二因素裂区试验设计,研究氮肥、密度及其互作对单粒精播花生根系形态、植株性状及产量的影响。氮肥对花生根长、根表面积、根体积、根干重的影响不显著,而密度的影响显著。单株根长、根表面积、根体积及根系干重随密度的增加而降低,D1显著高于D2和D3,D2、D3处理间差异不显著;单位面积根长、根表面积、根体积及根系干重随密度的增加而增加,D1显著低于D2和D3,D2、D3处理间差异不显著。氮肥和密度互作对2019年收获期单位面积根长、根表面积的影响显著,与D1相比,N1处理下D3的增幅显著高于N0和N2处理。氮肥及氮肥与密度互作对植株性状的影响存在年度和时期间的差异,主茎叶片数、侧枝数和主茎第一节间粗随密度增加有降低趋势。氮肥对荚果产量的影响不显著,荚果产量随密度的增加呈增加的趋势。产量与根体积、根干重、主茎叶片数、主茎高及侧枝长呈显著正相关。综上所述,在本试验条件下,花生单粒精播适宜的氮肥(N)水平为60 kg hm-2,种植密度为18.8万株hm-2。
文摘施氮对豆科作物土壤固氮菌的影响机理尚不明确。深入研究施氮对花生土壤固氮菌的影响,对花生田高效施氮和农业可持续发展具有重要意义。本研究以结瘤(花育22)和不结瘤(BL)花生为材料,设置N0(不施氮,0 kg hm^(-2))、N60(减量施氮,60 kg hm^(-2))、N120(常量施氮,120 kg hm^(-2))和N180(过量施氮,180 kg hm^(-2))4个施氮水平,探讨不同施氮水平对不同结瘤特性花生土壤固氮菌的影响。采用实时荧光定量PCR和高通量测序技术,以nifH基因为标靶,分析土壤固氮菌丰度、多样性和群落组成。结果表明:(1)施氮显著提高土壤氮组分含量,N120结瘤花生土壤中微生物量氮和可溶性有机氮显著高于不结瘤花生。不结瘤花生荚果产量随施氮水平呈线性增加,而结瘤花生产量不受施氮影响。(2)施氮条件下,不结瘤花生土壤nifH拷贝数显著降低,而结瘤花生土壤nifH拷贝数随施氮水平增加先降低后增加。(3)施氮对不结瘤花生土壤固氮菌多样性先抑制后促进,而施氮对结瘤花生土壤固氮菌多样性呈先促进后抑制的模式,并在N120达到最大值。(4)施氮显著改变不结瘤花生土壤固氮菌群落组成,不同施氮水平优势属分别为nonrank_Bacteria(N0)、unclassified_Cyanobacteria(N60)、nonrank_Bacteria(N120)和Skermanella(N180),硝态氮是影响处理间土壤固氮菌群落组成差异的唯一显著因素;结瘤花生土壤各施氮水平固氮菌群落组成相似,除N120外,均以unclassified_Proteobacteria和Skermanella占优。不结瘤与结瘤花生土壤固氮菌对施氮水平截然不同的响应可能是由于二者分别受到不同氮源的影响(肥料氮vs.根瘤固氮)。本研究中120 kg hm^(-2)是对土壤固氮和花生生产最优的施氮水平。
基金supported by the Youth Scientific Research Foundation of Shandong Academy of Agricultural Sciences, China(2014QNM27)the Applying Basic Research Project of Qingdao,Shandong Province,China(14-2-4-90-jch)+3 种基金the Modern Agricultural Industry Technology System,China (SDAIT-05-021-04)the National Key Technology R&D Program of China(2014BAD11B04)the Key Innovation of Science and Technology Project of Shandong Academy of Agricultural Sciences,China(2014CXZ06-22014CXZ11-2)
文摘Rational application of different forms of nitrogen（N） fertilizer for peanut（Arachis hypogaea L.） requires tracking the N supplied sources which are commonly not available in the differences among the three sources：root nodule,soil and fertilizer.In this study,two kinds of peanut plants（nodulated variety（Huayu 22） and non-nodulated variety（NN-1）） were choosed and four kinds of N fertilizers：urea-N（CONH_2-N）,ammonium-N（NH_4~＋-N）,nitrate-N（NO_3^--N） and NH_4~＋ ＋NO_3^--N labeled by^（15）N isotope were applied in the field barrel experiment in Chengyang Experimental Station,Shandong Province,China,to determine the N supplied sources and N use efficiency over peanut growing stages.The results showed that intensities and amounts of N supply from the three sources were all higher at middle growing stages（pegging phase and podding phase）.The accumulated amounts of N supply from root nodule,soil and fertilizer over the growing stages were 8.3,5.3 and 3.8g m^（-2） in CONH_2-N treatment,which are all significantly higher than in the other three treatments.At seedling phase,soil supplied the most N for peanut growth,then root nodule controlled the N supply at pegging phase and podding phase,but soil mainly provided N again at the last stage（pod filling phase）.For the whole growing stages,root nodule supplied the most N（47.8 and 43.0%） in CONH_2-N and NH_4~＋-N treatments,whereas soil supplied the most N（41.7 and 40.9%） in NH_4~＋ ＋NO_3^--N and NO_3^--N treatments.The N use efficiency was higher at pegging phase and podding phase,while accumulated N use efficiency over the growing stages was higher in CONH_2-N treatment（42.2%） than in other three treatments（30.4%in NH_4~＋-N treatment,29.4%in NO_3^--N treatment,29.4%in NH_4~＋ ＋NO_3^--N treatment）.In peanut growing field,application of CONH_2-N is a better way to increase the supply of N from root nodule and improve the N use efficiency.
基金Supported by the National Natural Science Foundation of China under Grant No.19574041the Natural Science Foundation of Fujian Province(F96005),the Special Doctoral Research Foundation of the Chinese State Commission of Education,and the Industrial Department of Xiamen Photo-Electron Company,。
文摘Electron structure of three series of alloy heterojunctions(GaAs)_(x)(Ge_(2))_(1-x)/Ge,(AlAs)_(x)(Ge2)_(1-x)/Ge and Al_(x)G_(1-x)As/Ge are calculated by linear muffin-tin orbital method with atomic-sphere approximation using the average-bond-energy theory in conjunction with a cluster expansion method.The results indicate the variations ofΔE_(v)(x)at heterojunctions(GeAs)_(x)(Ge2)_(1-x)/Ge and(AlAs)_(x)(Ge2)_(1-x)/Ge are nonlinear,which are very different from that of Al_(x)Ga_(1-x)As/Ge.
基金Supported by the National Natural Science Foundation of China under Grant No.19574041the Xiamen Photoelectron Company.
文摘The electronic structure of InAs_(0.25)P_(0.75)/InP strained quantum wires grown on InP(001)oriented substrates is studied within the framework of effective-mass envelope-function theory.At theΓpoint,the electron and valence subband energy levels with and without spin-split-off band,and the absorption spectra are calculated.The effects of strain and spin-split-off band on valence energy levels are presented.The results show that the uppermost valence subband is almost unaffected by the strain induced coupling between the heavy-and light-hole bands and the spin-split-off bands while the other subbands are more markedly affected in the InAs0.25P0.75/InP strained quantum wires.
