螯合-缓冲营养液中不同磷锌配比对小麦苗期磷-锌关系的影响

采用螯合-缓冲营养液培养方法对小麦进行了苗期培养试验,在3个磷水平(0、0.6 mmol·L-1、3.0mmol·L-1)和3个锌水平(0、3μmol·L-1、30 μmol·L-1)的完全组合下对小麦苗期的磷-锌关系进行了研究,以期为提高小麦籽粒锌的生物有效性提供理论依据.结果表明,与正常磷锌供应比较,磷锌的缺乏与过量均不利于小麦生长,缺磷比过量供磷的抑制程度更大,而过量供锌比缺锌的影响更为强烈,缺磷和过量供锌主要影响小麦幼苗的分蘖和地上部干物质的积累.过量供磷时,小麦根部存在明显的磷-锌拮抗,抑制了根部对锌的吸收,但磷的供应却提高了锌在小麦植株体内向地上部的转运;缺锌时,小麦叶片会积累大量磷,而供锌后则会抑制磷在小麦植株体内向地上部的转运.在小麦苗期,磷、锌均处于正常水平时其交互作用有利于锌的吸收和向地上部转运,但抑制了磷向叶部的转运.此外,磷、锌的缺乏均降低了叶绿素SPAD值,而磷的正常供应和锌的供应促进了叶绿素的合成.缺磷胁迫时小麦叶片的SOD和POD活性较高,而CAT活性较低;锌缺乏和过量时叶片SOD活性较低,而缺锌时POD和CAT活性较高,供锌后二者活性降低.总之,磷-锌拮抗作用主要发生在小麦根部,但在其他器官内也会发生;且不仅在二者配比不合理时发生,即使在配比合理时也会发生.     

磷锌配施对石灰性土壤磷锌有效性及小麦对其吸收分配的影响

针对磷锌在土壤-植物系统中复杂的交互作用,本文采用盆栽试验,研究了磷锌配施对石灰性土壤中磷锌有效性及小麦对其吸收分配的影响。结果表明,施锌明显增加了土壤中DTPA提取态锌含量,土壤中DTPA提取态锌含量随着施磷水平的提高逐渐增加;施磷明显增加了土壤中速效磷含量,在相同施磷水平下,土壤中速效磷含量随施锌量的增加而增加;施锌提高了小麦茎叶和籽粒锌含量,且在各施锌背景下随施磷量的增加明显地降低了小麦茎叶中锌含量,但提高了籽粒中锌含量。施磷提高了小麦茎叶和籽粒磷含量。在低磷水平(不施磷和施21.82 mg kg-1)时,施锌对茎叶中磷含量的提高作用明显,且随施锌浓度的提高而提高,但籽粒中磷含量逐渐降低;而在高磷水平(174.56 mg kg-1)下,施锌则降低了小麦植株茎叶中磷含量,而籽粒中磷含量却随施锌水平的提高而提高。因此,石灰性土壤中施磷肥提高了土壤中锌的有效性,而锌也提高了磷的有效性,同时发现施磷降低了小麦茎叶中锌含量,促进了锌元素从植株向籽粒的运输,增加了小麦籽粒中锌含量,但是在低磷条件下,施锌提高了茎叶磷含量,却降低了籽粒磷含量,而在高磷条件下,施锌降低了茎叶磷含量,提高了籽粒含量。     

螯合–缓冲营养液培养条件下添加外源锌对小麦幼苗生长和TaZIPs基因表达的影响

[目的]研究外源供锌对小麦幼苗根系发育、光合作用、金属离子平衡以及锌铁转运蛋白ZIP基因的表达,以期深入了解小麦的锌营养作用机理.[方法]采用水培试验方法,供试材料为冬小麦'百农207',试验共设置了5个锌(Zn)浓度处理:0?(Zn0)、0.05?(Zn0.05)、0.25?(Zn0.25)、1.0?(Zn1.0)和...     

施用磷和锌对植株体中锌营养及代谢的影响

A solution culture experiment was conducted to investigate the growth,the accumulation and translocation of Zn,and the metabolic changes of 24 days old plants of corn and wheat with the varied suply of phosphorus(0,0.12,0.6 and 3.0mmol L^-1)and zinc (0.1 and 2.0umol L^-1) under controlled environmental conditions.The results showed the highest dry matter production of both corn and wheat under the moder ate combination of phosphorus(0.6mmol L^-1) and zinc(2.0 umolL^-1) as compared with other imbalance applications of phosphorus and zinc.Excessive P supply significantly inhibited the translocation of Zn from roots of corn to the aboveground part,thus decreasing the content of Zn in the shoots.Application of 3.0 mmolL^-1 P could also reduce the water-soluble Zn in plant tissues,leading to an increase in the cell plasma membrane permeability,a decrease in the dehydrogenase activity in roots and the activity of nitrate reductase in leaves,and a decline in the uptake of nitrate by plants.A similar decrease occurred in superoxide dismutase(SOD) and plasma membrane adenosine triphosphatase(ATPase)activity in Zn-deficient plants.But,with increasing P supply the activity of ATP ase in both corn and wheat increased and reached the maximum at the P-supplying level of 3.0 mmolL^-1.Similar to the effect of high P supply.no or low P(0.12mmolL^-1) supply could be detrimental to dry matter production and physiological functioning of the plants.Corn plants showed a more significant response to the imbalance supply of P and Zn than wheat plants.The possible physiological and biochemical mechanism of phosphorus-zinc antagonistic interaction in corn and wheat might be attributed to decrease in physiological availability and activation of Zn.     

磷锌施用量对苗期玉米吸收ZnCuMn的影响

在温室条件下，以石灰性褐土和玉米为试验材料，研究了汪同Ｐ，Ｚｎ施用量对玉米苗期吸收Ｚｎ，Ｃｕ和Ｍｎ的影响，结果表明，农作物对营养元素的吸收是有平衡要求的，相互促进，相互制约，满足作物对大量元素供给，是发挥微量营养元素作用的前提，而过量的微量元素，则有可能成为有害因子危害作物的正常生长发育。     

低锌旱地施锌方式对小麦产量和锌利用的影响

西北地区是我国典型的旱地低锌区。本文选择黄土高原中部两个典型地点,通过田间试验,在两个施氮水平下,研究了不施锌、 土施锌、 叶喷锌和土施+叶喷锌4种方式对冬小麦产量、 锌的吸收和累积以及锌肥利用效率的影响。结果表明,不同施锌方式对小麦产量均无显著影响,但均提高了小麦子粒锌含量,提高幅度因施锌方式而异。与不施锌相比,叶喷和土施+叶喷锌肥可使小麦子粒锌含量提高40%左右,平均达到 40 mg/kg;单独土施锌肥虽使土壤有效锌提高3倍左右,但子粒锌含量无显著变化。叶喷锌肥的锌利用效率远高于土施和土施+叶喷处理,每公顷喷施1 kg锌可使小麦子粒锌含量提高6.70~13.04 mg/kg;子粒锌利用率为6.02%~9.40%, 达到土施锌肥的80倍左右;总锌利用率为19.78%~30.91%,是土施锌肥的132~221倍。施氮水平对小麦产量及锌肥利用效率均无显著影响。可见,在旱地低锌区,与土施锌相比,叶喷是更加经济有效、 环境友好的锌肥施用方式,是提高小麦锌营养品质切实可行的措施。     

小麦/玉米苗期磷累积量对介质供磷水平反应的差异

小麦和玉米苗期是磷素营养的关键期和敏感期,研究两种作物苗期对介质供磷反应,可为合理施用磷肥提供参考.试验设缺磷对照、低磷胁迫、中等磷胁迫和正常供磷(P2O5含量分别为0、0.05 mmol·L-1、0.3 mmol·L-1和0.5 mmol·L-1) 4种磷水平,选取小麦"小偃22号"、"兰考4号"和玉米"屯玉65号"、"户单4号"为指标作物,用营养液培养法研究小麦、玉米苗期磷累积量对介质不同供磷水平的反应差异.结果表明,不同介质供磷水平下,两种作物苗期磷累积量显著不同且因作物类型、基因型、器官及测定时期不同而异.总体而言,介质供磷后,苗期早期生长阶段(出苗后25 d以前),小麦的介质最佳供磷水平较玉米高;苗期后期(出苗后40～50 d),小麦和玉米最佳供磷水平一致.如果以低磷胁迫作为对比进行分析,玉米苗期整株磷累积量对介质供磷的敏感性比小麦强;从不同基因型来看:"兰考4号"对介质供磷的敏感性强于"小偃22号","屯玉65号"和"户单4号"基本一致.缺磷条件下小麦较玉米磷效率高,供磷条件下玉米较小麦高;但不同基因型间规律性较差.     

施锌对小麦开花后氮、磷、钾、锌积累和运转的影响

为明确大田条件下施锌对小麦地上部器官氮、磷、钾、锌的积累量和转移量的影响,2001～2002年开展了田间试验。试验以专用强筋小麦(8901-11)和普通小麦(4185)两个冬小麦品种为材料,包括4个施锌水平(分别为施ZnSO4.7H2O.0、11.25、22.5和33.75.kg/hm2)。结果表明,各器官中Zn的含量变化在4.14～54.18.mg/kg,刚开花时及灌浆前期的含量以子粒>穗壳>叶片>茎秆,至接近成熟时则以子粒>叶片>穗壳>茎秆。每生产100.kg小麦子粒需要吸收Zn的范围在4.40～5.20.g之间。小麦成熟时吸收的Zn约为N或K2O的1/800～1/700,为P2O5的1/500～1/300。施锌后小麦各器官氮、磷、钾、锌的积累量及开花后向子粒的运转量增加,但施锌过多,这些营养元素的吸收、积累和运转反而受到抑制。4185开花前吸收氮和磷的能力较强,而8901-11开花后吸收氮和磷的能力较强;而吸收钾和锌的能力与吸收氮和磷的情况相反。8901-11氮、磷、钾、锌的积累量基本随施锌量增加而提高,以施硫酸锌22.5～33.75.kg/hm2的积累量最高;而4185以施硫酸锌11.25.kg/hm2的积累量最高。因此,在施用大量元素的基础上,普通小麦以施硫酸锌11.25.kg/hm2为宜,而强筋小麦以施硫酸锌22.5～33.75.kg/hm2为宜。     

玉米、小麦细胞磷、锌营养及交互作用的研究

采用溶液培养研究玉米、小麦在不同磷、锌浓度下细胞磷、锌营养及交互作用。结果表明,随着外界磷浓度（０,０．１２,０．６,３．０ｍｍｏｌ／Ｌ）的提高,玉米、小麦根系和叶片细胞壁、细胞质和液泡中磷含量也随之增高,但细胞壁和液泡中磷的含量高于细胞质中的含量。介质中磷浓度的提高使根细胞壁中锌的含量增加,但高磷（３．０ｍｍｏｌ／Ｌ）处理使细胞质、液泡中锌的含量下降。高磷处理抑制了两种作物的锌由根系向地上部的转运,同时叶片中大部分锌被结合在细胞壁中,因而叶细胞中的细胞质和液泡处于相对的低锌状态。与足量锌（２．０ｍｏｌ／Ｌ）供应比较,低锌（０．１ｍｏｌ／Ｌ）处理使玉米、小麦根系和叶细胞壁、细胞质和液泡中磷的浓度增高。低锌和过量磷的供给抑制了植株的生长,最终使干物质的积累下降。     

长期施用磷肥对冬小麦根际磷、锌有效性及其作物磷锌营养的影响

以中国农业大学昌平试验站长期定位试验为基础,研究了长期施用磷肥对冬小麦根际磷锌有效性及其对作物磷锌营养的影响。结果表明,长期施用磷肥[P2O5,135.kg/(hm2.a)]导致土壤有效磷含量逐年提高;对根际和非根际土壤有效锌含量没有显著影响,但是根际土壤有效锌含量显著高于非根际土壤;长期施用磷肥冬小麦抽穗期植株锌含量显著低于不施磷处理;无论拔节期和抽穗期,植株含磷量和植株磷锌比(P/Zn)都随着施磷量的增加而显著增加。长期施用磷肥处理(P1和P2)在显著提高了冬小麦子粒含磷量的同时,显著降低了其含锌量;冬小麦子粒磷锌比(P/Zn)随着施磷量的增加也显著增加,子粒含磷量与含锌量呈极显著的负线性相关关系。     

Zinc nutrition effect on the tolerance of wheat genotypes to Fusarium root-rot disease in a solution culture experiment

Abstract

Zinc (Zn) nutrition and plant genotype are two factors that may affect the tolerance of wheat to root-rot diseases. The aim of the present study was to determine the effect of Zn on shoot yield, root permeability and infection by Fusarium solani in six wheat genotypes with different Zn efficiency. A greenhouse (solution culture) experiment was carried out in which five bread wheat genotypes (Triticum aestivum L. cvs Rushan, Kavir, Cross, Pishtaz and Falat) and one durum wheat genotype (Triticum durum L. cv. Yav79), which are common in Zn-deficient soils of Iran and were exposed to two levels of Zn (0 and 1?μmol?L^–1?Zn?kg^?1, as ZnSO₄.7H₂O) and two F. solani infection levels (0 and 10⁶?spore?mL^?1). Zinc deficiency significantly decreased shoot dry matter in five of the genotypes (Yav79, Kavir, Rushan, Cross and Falat), but had no effect on shoot growth in Pishtaz. Infection with F. solani significantly decreased the shoot dry matter in Yav79, but did not affect the shoot dry weight of the other wheat genotypes. Root membrane permeability was lower in the Zn treatments than in the Zn-free treatments. Zinc deficiency caused a decrease in root reactive sulfhydryl (SH) groups, particularly in the Cross genotype. Root sulfhydryl groups decreased with Fusarium infection. Zinc application sharply increased the Zn content and decreased the Mn content of the shoots. Application of Zn had a positive effect on the tolerance of wheat to F. solani root rot. The relationship between Zn nutrition and disease tolerance suggests that Zn deficiency should be treated before evaluating the cost-effectiveness of fungicides. No correlation was found between the Zn efficiency of the wheat genotypes and Fusarium root-rot disease severity in this solution culture experiment.     

Genotypic variation for nitrogen uptake and assimilation using hydroponic culture technique in wheat

Hydroponic culture technique is an alternative way of studying nitrogen metabolism. In this study, the response of six wheat genotypes (PBW 621, PBW 636, GLU 1356, BW 8989, GLU 700, and PBW 343) with respect to nitrogen-metabolizing enzymes in relation to accumulation of soluble proteins and amino acids at two concentrations of nitrogen (2 and 6 mM) was studied. Activities of nitrate reductase (NR) and glutamine synthetase as well as soluble proteins, amino acids, and nitrogen content increased in all six genotypes with increasing concentration of nitrogen in roots as well as shoots. Shoots maintained higher activities of NR and glutamine synthetase; apparently contents of soluble protein, amino acid, and nitrogen were also higher. The upregulation of NR and glutamine synthetase activities with increased concentration of nitrogen possibly contributes to higher nitrogen assimilation efficiency of three genotypes (PBW 621, PBW 636, and GLU 1356) compared to other genotypes.     

Nitrogen and phosphorus use efficiency of 43 wheat alien chromosome addition lines evaluated by hydroponic culture

Wild relatives of wheat may possess useful traits or genes for efficient use of nitrogen (N) or phosphorus (P). Forty-three wheat addition lines with alien chromosomes from Leymus, Agropyron, Hordeum, Psathyrostachys, Aegilops, and Secale cereale, along with their common parent Chinese Spring (CS) were cultured by hydroponics, and their phenotypic variation, N/P uptake and utilization efficiency were investigated at seedling stage. The phenotypic variation showed that N deficiency decreased plant height, shoot dry weight, and total dry weight, while increased root length, number of leaves, SPAD value, and root to shoot ratio (R/S); while P deficiency decreased all the measured traits except root dry weight and R/S. Aegilops longissima 2S and Aegilops searsii 4SS addition lines were identified as both N- and P-efficient germplasm, of which Ae. longissima 2S addition line showed significant increased N and P uptake efficiency than CS under all treatments.     

离体培养下锌对春小麦子粒形成及干物质积累的影响

采用离体穗培养技术研究了锌对春小麦后期生长及产量的影响。结果表明,在Zn2+浓度为6.mmol/L的处理小麦的生长发育状况最好,其旗叶内叶绿素含量、倒一节长度、穗粒数、结实率、千粒重以及穗的干重与对照相比差异均达到显著或极显著水平;倒二节长度和小花数与对照的差异不显著。低锌和锌过量(Zn2+浓度为0.3和300mmol/L)条件下,小麦的生长发育受阻,各项性状指标均低于对照,不利于产量的提高;而且锌过量不但降低产量还造成锌肥的浪费和环境污染。     

Phosphorus-induced zinc deficiency in wheat pot-grown on noncalcareous and calcareous soils of different properties

High levels of phosphorus (P) often induce zinc (Zn) deficiency in plants grown on Zn-poor soils. We investigated P-induced Zn deficiency in durum wheat (Triticum durum L. ‘Carpio’) grown on 16 noncalcareous and 31 calcareous soils differing in levels of available (Olsen) P and available (diethylenetriaminepentaacetic acid (DTPA)-extractable) Zn using micropots. A completely randomized factorial design with two levels of P (0 and 40 mg P kg^?1 soil) and Zn (0 and 3 mg Zn kg^?1 soil), i.e. four treatments (‘control’, + P, + Zn, and + PZn), were used. Grain yield of control plants depended mainly on the Olsen P level. Phosphorus had a negative effect on yield in 6 soils with Olsen P/Zn_DTPA > 25, and Zn a positive one in 5 soils with Olsen P/Zn_DTPA > 50; and the + PZn treatment generally resulted in the highest yield. Grain Zn concentration of control plants was negatively correlated with growth and Olsen P. Calcareous soils were less sensitive to P-induced Zn deficiency than noncalcareous soils because phosphate is sorbed by calcite rather than being co-adsorbed with Zn on the Fe oxides. Co-application of P and Zn to soil at low and application of Zn at high Olsen P ensured both maximum yield and grain Zn bioavailability.     

水磷互作对黑垆土春小麦生长及产量的影响

在温室条件下进行了黑垆土水磷互作对春小麦生长及产量影响的研究。结果表明,水分和磷素对春小麦苗期与抽穗期内株高和叶面积皆有一定影响,但交互作用的表现不同;适宜的水分与磷素配合既满足了春小麦物质生产过程中对水分和营养元素的需求,又促进了春小麦生长发育,提高了生物产量、经济产量及水分生产效率,从而可以达到以水促磷和以磷促水的目的;而缺水高磷组合或高水低磷组合均不利于春小麦生长发育,其产量与水分生产效率也较低。     

不同形态无机磷对两种磷效率小麦根际特征的影响

以磷高效型小麦小偃54和磷低效型小麦京411为材料的砂培试验,通过测定植株生物量及吸磷量、根系形态特征、根际pH、磷酸酶活性,研究不同形态无机磷WP(KH2PO4),Al-P(AlPO4)和Fe-P(FePO4)对两种磷效率小麦根际特征的影响.结果表明,在WP处理下,两种磷效率小麦的地上部吸磷量、总吸磷量和磷吸收效率均显著高于其它处理,而其根冠比和磷利用效率却低于其他处理.除了根部吸磷量,小偃54的生物量和吸磷量有高于京411的趋势.除了WP处理,其他处理的小偃54的根冠比和地下吸磷量均高于京411.所有处理的小偃54的根长和根体积均显著高于京411,且不施磷条件(PO)下更为明显,小偃54根系长度是京411的1.6倍;此外,小偃54根系磷酸酶活性均比京411弱.除Al-P外,小偃54的根际酸化能力较京411强.由此可见,磷胁迫条件下,磷高效小麦根系形态特征改变是根际磷活化的主要机理之一,且受磷水平、磷形态及其溶解性的影响.