Evaluation and utilization of <Emphasis Type="Italic">Aegilops</Emphasis> and wild <Emphasis Type="Italic">Triticum</Emphasis> species for enhancing iron and zinc content in wheat

Grains of 80 accessions of nine species of wild Triticum and Aegilops along with 15 semi-dwarf cultivars of bread and durum wheat grown over 2 years at Indian Institute of Technology, Roorkee, were analyzed for grain iron and zinc content. The bread and durum cultivars had very low content and little variability for both of these micronutrients. The related non-progenitor wild species with S, U and M genomes showed up to 3–4 folds higher iron and zinc content in their grains as compared to bread and durum wheat. For confirmation, two Ae. kotschyi Boiss. accessions were analyzed after ashing and were found to have more than 30% higher grain ash content than the wheat cultivars containing more than 75% higher iron and 60% higher zinc than that of wheat. There were highly significant differences for iron and zinc contents among various cultivars and wild relatives over both the years with very high broad sense heritability. There was a significantly high positive correlation between flag leaf iron and grain iron (r = 0.82) and flag leaf zinc and grain zinc (r = 0.92) content of the selected donors suggesting that the leaf analysis could be used for early selection for high iron and zinc content. ‘Chinese Spring’ (Ph ^I ) was used for inducing homoeologous chromosome pairing between Aegilops and wheat genomes and transferring these useful traits from the wild species to the elite wheat cultivars. A majority of the interspecific hybrids had higher leaf iron and zinc content than their wheat parents and equivalent or higher content than their Aegilops parents suggesting that the parental Aegilops donors possess a more efficient system for uptake and translocation of the micronutrients which could ultimately be utilized for wheat grain biofortification. Partially fertile to sterile BC₁ derivatives with variable chromosomes of Aegilops species had also higher leaf iron and zinc content confirming the possibility of transfer of required variability. Some of the fertile BC₁F₃ and BC₂F₂ derivatives had as high grain ash and grain ash iron and zinc content as that of the donor Aegilops parent. Further work on backcrossing, selfing, selection of fertile derivatives, leaf and grain analyses for iron and zinc for developing biofortified bread and durum wheat cultivars is in progress. Nidhi Rawat, Vijay K. Tiwari, and Neelam Singh have contributed equally to the work.     

Infection, immunity and the neuroendocrine response

The Central Nervous (CNS) and Immune Systems (IS) are the two major adaptive systems which respond rapidly to numerous challenges that are able to compromise health. The defensive response strictly linking innate to acquired immunity, works continuously to limit pathogen invasion and damage. The efficiency of the innate response is crucial for survival and for an optimum priming of acquired immunity. During infection, the immune response is modulated by an integrated neuro-immune network which potentiates innate immunity, controls potential harmful effects and also addresses metabolic and nutritional modifications supporting immune function. In the last decade much knowledge has been gained on the molecular signals that orchestrate this integrated adaptive response, with focus on the systemic mediators which have a crucial role in driving and controlling an efficient protective response. These mediators are also able to signal alterations and control pathway dysfunctions which may be involved in the persistence and/or overexpression of inflammation that may lead to tissue damage and to a negative metabolic impact, causing retarded growth.This review aims to describe some important signalling pathways which drive bidirectional communication between the Immune and Nervous Systems during infection. Particular emphasis is placed on pro-inflammatory cytokines, immunomodulator hormones such as Glucocorticoids (GCs), Growth hormone (GH), Insulin-like Growth Factor-1 (IGF-1), and Leptin, as well as nutritional factors such as Zinc (Zn).Finally, the review includes up-to-date information on this neuroimmune cross-talk in domestic animals. Data in domestic animal species are still limited, but there are several exciting areas of research, like the potential interaction pathways between mediators (i.e. cytokine-HPA regulation, IL-6-GCS-Zn, cytokines-GH/IGF-1, IL-6-GH-Leptin and thymus activity) that are or could be promising topics of future research in veterinary medicine.     

鹰嘴豆锌指蛋白基因ZF1的克隆及表达分析

利用一段从PEG胁迫的鹰嘴豆幼苗叶片所构建的cDNA文库中得到的EST序列,通过3¢RACE方法克隆到一个鹰嘴豆C₂H₂型锌指蛋白基因ZF1,该基因不含内含子,编码一条244个氨基酸残基的多肽,含有两个典型的Cys2/His2锌指结构。其氨基酸序列含有一个可能的核定位型号,农杆菌介导的洋葱表皮细胞GFP瞬时表达实验表明,ZF1蛋白位于细胞核内。半定量RT-PCR分析表明,ZF1在鹰嘴豆的根、茎、叶、花、幼荚和幼胚中均有表达,在茎和叶中表达较弱,为组成型转录因子。半定量RT-PCR和实时荧光定量PCR检测结果显示,ZF1不但受高温及干旱诱导,而且还受6-苄基腺嘌呤(6-BA)、脱落酸(ABA)、乙烯利(Et)、赤霉素(GA₃)、吲哚-3-乙酸(IAA)、茉莉酸甲酯(MeJA)、水杨酸(SA)和氧胁迫诱导。这些结果表明,ZF1基因可能作为一个核调控因子参与植物的生长代谢以及多种生物与非生物胁迫的应答。     

十和田近等基因系糙米锌含量QTL定位

以十和田为轮回亲本,丽粳2号为供体亲本培育出糙米锌含量近等基因系群体BC5F6为材料,从遍布水稻12条染色体上的600对引物中筛选到一个与糙米锌含量有关的SSR标记RM4608.根据其在水稻染色体上的位置,结合PCR扩增结果又发现了与糙米锌含量有关的4个SSR标记(RM19491,RM19489,RM6119和RM19487).用MAPMAKER3.0软件做出了这5个标记的连锁群,最后采用混合线性模型定位法找到了糙米锌含量的QTL位点.QTL分析结果显示:该位点位于6号染色体上RM4608和RM6119标记之间,贡献率为5%,为新发现的与糙米锌含量有关的微效基因位点,暂命名为qZINC-6.同时与糙米铬和镁含量有关的QTL位点也被发现,其中糙米铬含量QTL位于标记RM19489和RM19491之间,贡献率为9%,是一个主效基因;糙米镁含量QTL位于标记RM4608-RM6119之间,是一个微效基因,贡献率为4%.     

锌对根霉和酵母生长的影响

[目的]选出最适合根霉与酵母生长的锌浓度,为含锌根霉及酵母的生产提供理论依据。[方法]分别从4个酒曲厂的酒曲中分离纯化得到根霉和酵母菌种,用不同锌浓度的液体培养基培养,观测其菌落的生长情况并对其生物量进行统计分析。[结果]来自后山湾的酒曲的根霉生长最好,来自金子坝的酒曲的酵母生长最好。不同浓度锌时根霉与酵母生长的影响有较大的不同,当锌浓度在0-1mg／L范围内时,孢子长势较好,孢子数增加了1倍;当锌浓度超过5mg／L时,孢子数下降,且锌浓度越高孢子数越少。锌浓度为1mg/L时最适合两株菌生长。当锌浓度在0～1mg／L范围内时,菌落生长良好,1mg／L锌浓度的菌落重量为无锌菌落的两倍。[结论]低浓度锌促进根霉与酵母的生长,高浓度锌抑制其生长。     

不同氮磷锌施肥水平对盐碱地牧草生物产量的影响

［目的］优化氮磷锌肥配比施用量。［方法］选择苜蓿、草木樨、星星草、沙打旺、羊草等耐盐牧草,采用311-A最优回归设计,比较氮磷锌施肥水平。 ［结果］最高产草量16 534.10 kg/hm^2,相应的氮肥、磷肥、锌肥用量分别为116.55 、121.35 、31.20 kg/hm^2;最佳经济效益牧草产量16 233.90 kg/hm^2,相应的氮肥、磷肥、锌肥用量分别为116.40、121.20、30.90 kg/hm^2,纯收益为2 472.40元/hm^2。［结论］对牧草产量影响的顺序依次是磷肥、氮肥和锌肥。     

农田黑土铜、锌吸附解吸特性分析

研究了铜、锌在双城、海伦、方正农田黑土中的吸附解吸行为.3地土壤吸附Cu2+、Zn2+的量均随着平衡液中Cu2+、Zn2+质量浓度的增加而增大.双城、海伦、方正农田黑土对Cu2+的吸附解吸行为用Freundlich方程拟合最佳,吸附态Cu2+的解吸有明显滞后现象,而且3地土壤吸附态Cu2+的解吸率均较低.供试土壤对Zn2+的吸附行为用Freundlich方程拟合最佳,而对Zn2+的解吸行为用Langmuir方程拟合最佳.     

锌对黄瓜幼苗根系生长及保护酶活性的影响

为促进科学合理施用微量元素肥料、培育黄瓜壮苗,进一步提高黄瓜产量和品质,以‘新津春4号’黄瓜为材料,缺锌的1/2 Hoagland营养液为基础,设置4个不同浓度的ZnSO4?7H2O处理(0、0.1、0.2、0.4 mg/L)。通过营养液水培的方法,研究不同锌浓度对黄瓜幼苗根系生长及保护酶活性的影响。结果表明：（1）随着锌浓度的增加,黄瓜幼苗根系的总长度、平均直径、总面积、总体积、根尖数逐渐提高,Zn3(0.4 mg/L)时达到最大。（2）在Zn0(0 mg/L)到Zn2(0.2 mg/L)范围内,随着锌浓度的提高,POD、CAT活性升高,当锌浓度大于Zn2时,POD、CAT活性降低;SOD活性随着锌浓度的增加显著提高;丙二醛(MDA)含量随着锌浓度的增加显著降低。（3）综合考虑的黄瓜生长生理指标,黄瓜幼苗根系生长的最佳ZnSO4?7H2O浓度为0.2 mg/L的1/2 Hoagland营养液。     

叶面喷施微肥对冬小麦产量和品质的影响

为给小麦高产优质栽培中微肥施用提供参考,以冬小麦品种石新828为材料,研究了叶面喷施锌、铁、硒3种微肥对小麦产量、籽粒锌、铁、硒和蛋白质含量的影响。结果表明,3种微肥中只有喷硒增产作用显著(P<0.05),但喷锌、铁、硒分别显著增加了千粒重、穗数和穗粒数。3种微肥均能明显提高籽粒中相应的微量元素含量,但对籽粒蛋白质含量影响均不显著。     

弹簧垫圈断裂原因分析

通过宏观检验观察、化学成分分析、硬度测试、金相检验和断口分析等方法对弹簧垫圈的断裂原因进行分析。结果表明:该弹簧垫圈热处理时产生淬火裂纹,镀锌时氢原子在裂纹尖端偏聚,这两种因素的共同作用导致弹簧垫圈在装配预紧过程中发生脆性断裂。