The genetic architecture of zinc and iron content in maize grains as revealed by QTL mapping and meta-analysis

Micronutrient malnutrition, especially zinc (Zn) and iron (Fe) deficiency in diets, has aroused worldwide attention. Biofortification of food crops has been considered as a promising approach for alleviating this deficiency. Quantitative trait locus (QTL) analysis was performed to dissect the genetic mechanism of Zn and Fe content in maize grains using a total of 218 F_2:3 families derived from a cross between inbred lines 178 and P53. Meta-analysis was used to integrate genetic maps and detect Meta-QTL (MQTL) across several independent QTL researches for traits related to Zn or Fe content. Five significant QTLs and 10 MQTLs were detected. Two informative genomic regions, bins 2.07 and 2.08, showed a great importance for Zn and Fe content QTLs. The correlation between Zn and Fe level in maize grains was proposed by MQTLs as 8 of the 10 involved both traits. The results of this study suggest that QTL mapping and meta-analysis is an effective approach to understand the genetic basis of Zn and Fe accumulation in maize grains.     

Cu2+和Zn2+胁迫对玉米幼苗生理特性的影响

研究在Cu2+和Zn2+的胁迫下,玉米幼苗一些生理指标的变化,结果表明:在Cu2+和Zn2+的胁迫下,玉米幼苗生长发育受到抑制,较高浓度的Cu2+和Zn2+显示较高的毒性.在Cu2+和Zn2+的处理下,玉米幼苗的叶绿素、可溶性蛋白质、过氧化物酶(POD)、脯氨酸的含量下降,叶片中铜、锌、丙二醛(MDA)的含量增加.同时,Cu2+和Zn2+浓度的高低对玉米的生理特性的影响不同,且玉米幼苗对Cu2+的胁迫更为敏感.     

公路沿线水稻植株的重金属污染研究

以盆栽水稻为研究对象,通过重金属含量的测定,研究公路沿线环境中重金属对水稻植株不同组织的污染程度.结果表明:Pb、Zn、Cu、Cd在水稻中均表现出距离上的显著积累特征,其中盆栽水稻籽粒中的Pb含量超过规定值93.8～196.3倍,若食用对人体危害极大.因此,在实际的农业生产过程中,应尽量避免在距离公路较近的区域种植水稻等被人类直接食用的农作物.     

Dynamics of some mineral nutrients and heavy metals in decomposing forest litter

The dynamics of three major mineral nutrients (K, Ca, Mg) and six heavy metals (Fe, Mn, Zn, Cu, Pb and Cd) were studied in decomposing natural, unpolluted litter in two forest types: Scots pine needle litter in a pure Scots pine forest and oak‐hornbeam leaf litter in a mixed oak‐hornbeam stand. Of the mineral nutrients, only K in the oak‐hornbeam system showed a significant decrease in concentration during the course of litter decomposition. For Ca and Mg in both systems and for K in the Scots pine system no clear relation between concentration and accumulated litter‐mass loss was observed. On the other hand, for Fe, Zn, Pb and Cd at both sites, as well as for Mn in the oak‐hornbeam stand and Cu in the Scots pine stand highly significant positive relations were found between heavy metal concentrations and accumulated mass loss. A decrease in concentration was noted only in the case of Mn in the Scots pine system. No clear pattern was found for Cu in the oak‐hornbeam stand. Concentrations of heavy metals in the decomposing litter reached levels at or above those reported to retard decomposition in other studies. At the oak‐hornbeam stand increased also the absolute amounts of Fe, Zn, Pb and Cd.     

氮、磷、锌肥对纤维亚麻产量的效应

采用“311-B”最优回归设计,通过亚麻田间试验取得的产量数据,建立亚麻N、P、Zn肥的肥料效应函数,解析了各因素对亚麻产量的效应,提出高产纤维亚麻的施肥配方。     

吸附动力学及其机制分析

以竹炭粉和壳聚糖为原料，制备竹炭/壳聚糖复合吸附剂，进行扫描电镜（吸收光谱SEM）、红外吸收（FTIR）、X-射线衍射（XRD）等图谱表征，并进行Zn²⁺吸附试验。结果表明：①壳聚糖较好地负载在竹炭上，凸凹不平明显，蜂窝增强；复合吸附剂对Zn²⁺的吸附率在80 min后达到93%。②竹炭/壳聚糖复合吸附剂对Zn²⁺吸附过程的动力学表明，吸附过程符合多孔结构的吸附特征，方程拟合结果更符合二级动力学模型。③Zn²⁺吸附前后的红外吸收图谱表明，与竹炭/壳聚糖复合吸附剂吸附配位主要发生在—NH2中的氮原子、—OH和C＝O中氧原子上。图9参11     

不同品种杞柳对高锌胁迫的忍耐与积累研究

采用营养液培养实验方法,研究了高浓度Zn对3个杞柳品种"微山湖","大红头"、"一枝笔"生长,耐性及Zn吸收积累的影响.结果表明,Zn对杞柳生长的影响与品种、植物部位以及介质中Zn浓度有关,低Zn(100 μmol·L-1)、高Zn(1 000 μmol·L-1)均不同程度降低了3个杞柳品种的生长参数,低Zn显著减少了"微山湖"、"大红头"的根长及"大红头"根生物量,高Zn显著降低了3个品种株高、根长、生物量等生长参数;3个品种对Zn吸收与积累存在一定差异,地上部Zn含量随介质中Zn浓度升高而降低,根系中Zn含量随Zn浓度升高而增加,Zn在根中含量高于地上部,低Zn时3个品种地上部Zn含量为1477.58～1 583.19 μg·g-1,平均1 530.29 μg·g-1;位移系数(TF)随Zn浓度升高而降低,低Zn时"微山湖"、"一枝笔"位移系数高于"大红头"而接近1;迁移总量随Zn处理浓度增加而降低,3个品种迁移总量为2 332.58～3 871.41 μg,平均3 266.27μg,迁移总量比大于1;耐性指数(TI)随营养液中Zn浓度增加而降低,低Zn时3个品种耐性指数均大于0.5.以上结果表明,高Zn严重干扰了3个杞柳品种的生长,3个品种对低Zn有较强的耐性及积累能力,显示出具有修复≤100 μmol·L-1Zn潜力.     

钾及钾锌配施对夏玉米生长发育和产量的影响

试验采用裂区设计,研究了不同施钾量的条件下,钾及钾锌配施对夏玉米生长发育及产量的影响。结果表明:单施钾肥增产553.0～2292.0kg/hm2,配施钾锌肥可增产1062～2692.5kg/hm2。经回归分析,单施和配施的最佳施肥量(K2O)分别为275.8kg/hm2和283.5kg/hm2。与单施钾肥相比,配施更能有效的促进夏玉米生长发育,增加次生根数,降低秃尖,改善穗部性状,提高抗病能力。     

黄土高原潜在缺锌区施用纳米氧化锌（ZnO NPs）对冬小麦生长及籽粒品质的影响

为研究纳米氧化锌的施用方式对冬小麦生长及籽粒品质的影响,本研究在黄土高原潜在缺锌地区进行田间微区试验,使用传统的七水硫酸锌(ZnSO_4·7H_2O)和新型的纳米氧化锌(ZnO NPs)作为锌肥,设置对照(CK)、喷施硫酸锌(FZn)、土施ZnO NPs(SZnO)、喷施ZnO NPs(FZnO)和土喷结合ZnO NPs(SFZnO)五个处理。结果表明,不同处理对于冬小麦产量及其构成因素和籽粒品质(淀粉、可溶性糖和谷蛋白)未造成显著影响。ZnO NPs处理相比CK,在两季均显著提高了冬小麦的籽粒锌含量。对比硫酸锌处理,FZnO和SFZnO比FZn处理的籽粒锌含量在第一年分别提高了36%和45%,在第二年分别提高了12%和24%。拔节期叶片扫描表明FZn处理与CK的叶片结构没有差异,FZnO处理观察到颗粒表面附着,能谱仪扫描确定FZnO处理的锌含量显著高于FZn处理和CK。五个不同处理结果表明,小麦施用ZnO NPs比施硫酸锌有较显著的增锌效果,不同施用方式以土喷结合处理增锌效果最佳,籽粒锌含量达到37 mg·kg~(-1),单独喷施处理的锌转移吸收效率最高。施用ZnO NPs对小麦生长、籽粒品质以及叶片生理结构没有产生不良影响,ZnO NPs可作为新型锌肥应用于农业研究。     

不同施肥模式下玉米-土壤系统磷锌的动态变化

[目的]研究不同施肥模式下玉米-土壤系统磷锌的动态变化规律,为制定合理的玉米高产施肥模式提供理论依据。[方法]采用田间试验法,研究不同施肥模式下玉米干物质积累、产量及磷锌的动态变化规律。[结果]随着生育期的延长,各处理玉米干物质和磷锌积累量均呈＂S＂型变化;不同施肥模式中,各生育时期高产田的土壤速效磷较常规田和低产田分别提高6.2%~15.2%和41.6%~87.0%;成熟期植株干物重分别提高8.3%和25.4%,植株磷累积量分别增加14.6%和43.5%,植株锌累积量分别增加40.2%和74.0%。[结论]高产田中有机无机肥合理配施,玉米增产效果显著,产量达12 286.7 kg/hm2。