Identification of the HAK gene family reveals their critical response to potassium regulation during adventitious root formation in apple rootstock

Adventitious root formation is a bottleneck during vegetative proliferation.Potassium(K^(+))is an essential macronutrient for plants.K^(+)accumulation from the soil and its distribution to the different plant organs is mediated by K^(+)transporters named K^(+)transporter(KT),K^(+)uptake(KUP),or high-affinity K^(+)(HAK).This study aimed to identify members of the HAK gene family in apples and to characterize the effects of K^(+)supply on adventitious root formation and on the expression of HAK genes and the genes that putatively control auxin transport,signaling,and cell fate during adventitious root formation.In this study,34 HAK genes(MdHAKs)were identified in the apple(Malus×domestica‘Golden Delicious’)genome.A phylogenetic analysis divided MdHAKs into four clusters(Ⅰ,Ⅱ,Ⅲ,andⅣ),comprising 16,1,4,and 13 genes,respectively.The syntenic relationships revealed that 62.5%of the total MdHAK genes arise from genomic duplication events.Chromosome location,domain structure,motif analysis,and physico-chemical characteristics were subsequently investigated.Furthermore,the application of K^(+)indicated the emergence of adventitious roots at 8 d and produced more adventitious roots at 16 d than the K^(+)-free control(CK)treatment.In addition,various MdHAKs showed root-specific expression in B9 apple rootstock stem cuttings and enhanced expression during the initiation and emergence stages of adventitious root formation in response to K^(+)treatment.Additionally,K^(+)treatment enhanced the expression levels of MdPIN1,MdPIN2,and MdAUX1.Further data indicated that a higher expression of MdWOX11,MdLBD16,and MdLBD29 and of cell cycle-related genes contributed to the auxin-stimulated adventitious root formation in response to K^(+).

电/高锰酸钾/过一硫酸盐体系降解活性黄K-RN及其机理

印染废水中的有机染料处理在水处理技术中长久以来都是一大难题,电/高锰酸钾/过一硫酸盐体系(EC/PM/PMS体系)可以高效地降解活性黄K-RN等难降解有机污染物,但其降解机制还尚未明确,且锰类物质能否活化PMS产生活性物质以及PMS活化机理还需进一步探究。因此,本文研究了EC/PM/PMS体系在降解印染废水时活性物质的类别和产生途径,同时确定了锰类物质在其中的作用机理和PMS的活化过程。结果表明,EC/PM/PMS体系是一种包含自由基氧化和非自由基氧化的复合体系,体系中由PM还原生成五价锰、六价锰和无定形二氧化锰活化PMS。此外,明确了活性氧类自由基氧化是活性黄K-RN降解的主要路径,占比为95.3%,电极直接氧化占比2.1%,非自由基氧化占比仅为2.6%。

Effect of Potassium on Ultrastructure of Maize Stalk Pith and Young Root and Their Relation to Stalk Rot Resistance

To study the mechanism of potassium （K） application on improvement of maize resistance to stalk rot at cellular level, scanning electron microscope and transmission electron microscope were used to observe the effect of K on the ultrastructure of maize stalk pith tissue and young root tip cell influenced by K and pathogen. In K deficient treatment, parenchyma cells of stalk pith had abnormal structure, and the cell wall between upper and lower adjacent cell was damaged, resulting in the loss of connections between vascular cells and insufficient supporting capacity. However, an improved K nutrition helped to keep a quite tight arrangement of root cell with thick cell wall, and prevent the invasion of pathogen effectively. Moreover, K treated root cell had abundant golgi apparatus, which could excrete large amount of secretions to degrade mycelium. Papillary and highly electronic intensity dot were accumulated at the invading point to prevent the deveJopment of the mycelium. Improved K nutrition could increase the resistant ability of maize plant to stalk rot, through keeping cell structure stability, preventing the expansion of intracellular space to reduce the chances of pathogen invasions, and through reinforcing cell wall and formation of intercellular and intracellular material to restrict further development of pathogen in host cell.

Baeyer-Villiger oxidation of cyclic ketones utilizing potassium peroxydisulfate(K_2S_2O_8) or sodium perborate(NaBO_3) in acidic media

The efficient, green, facile, mild and straightforward conversion procedure for the oxidation of cyclic ketones to lactones at room temperature utilizing potassium peroxydisulfate （K2S2O8） in acidic media is satisfactory to high yields without using traditional chlorinated solvents is reported. This oxidative reagent is cheap and friendly environmental procedure for industrial purposes than use of organic peracids.

萝卜HAK/KUP/KT基因家族鉴定与表达特性分析

钾元素是植物生长发育过程中必需的主要矿质营养元素之一,对作物的产量和品质有决定性影响,细胞内K+含量水平在很大程度上受K+转运蛋白控制。通过生物信息学方法从全基因组水平鉴定出萝卜K^(+)转运蛋白HAK/KUP/KT基因家族成员,并对其基因结构、蛋白质特性、保守基序、染色体定位、启动子顺式作用元件、系统进化及表达特性等进行分析。结果表明,鉴定出的17个萝卜HAK/KUP/KT基因不均等地分布在萝卜6条染色体及Scaffold00840上,根据与拟南芥的同源关系将其命名为RsHAK1~RsHAK17;RsHAKs基因结构、保守基序、蛋白质理化特性等均具有高度保守性,启动子区域存在大量与环境因素、植物激素、逆境胁迫应答等有关的顺式作用元件;系统进化分析结果显示,17个RsHAKs基因聚为4个亚家族,全基因组复制事件是RsHAKs基因扩张的主要驱动力。转录组和qRT-PCR表达分析结果表明,除RsHAK5仅在萝卜根部表达外,其他RsHAKs在萝卜各器官及发育过程中均有特异性表达,且在高钾渗透胁迫下在叶片中相对表达量显著上调,RsHAK3、RsHAK9、RsHAK11和RsHAK12在根部呈现明显的缺钾诱导表达模式。研究结果为进一步全面解析HAK/KUP/KT基因在萝卜中的生物学功能以及提高萝卜栽培品质提供了一定理论依据。

20 Years Advances in Preparation of Potassium Salts from Potassic Rocks:A Review

Long-term research on key techniques of clean utilization of potassic rocks from over twenty localities has been performed to settle the shortage of soluble potassium resources in China. The results show that K-feldspar as the principal mineral enriched in potassium could be decomposed in the media of Ca（OH）_2, NaOH, KOH-H_2O solution via hydrothermal treatment, into tobermorite, hydroxylcancrinite, and kalsilite respectively. By further processing, these compounds are feasible for being as slow-release carrier of potassium nitrate, extracting alumina, and preparing farm-oriented fertilizers of potassium sulphate and nitrate. Correspondingly, the filtrate is KOH,（Na, K）_2SiO_3, and K_2SiO_3 solution, from which potassium carbonate, sulphate, nitrate, and phosphate could be easily fabricated. As NaO H and KOH are recycled in the processing chains by causticizing sodium and/or potassium metasilicate solutions, the hydrothermal alkaline techniques as developed in this research have several advantages as lower consumption of disposable mineral resources and energy, maximized utilization of potassic mineral resources, as well as clean productions etc. Based on the approaches presented in this paper, the technical system of efficiently utilizing insoluble potassium resources has been established. The hydrothermal alkaline methods are feasible to be industrialized on a large scale, thus resulting in decreasing imports of potash fertilizers, improving the pattern of potassium fertilizer consumption, and enhancing the supplying guarantee of potassium resource in China.

Preparation of Layered Potassium Titanate Whiskers with Large Length-diameter Ratio by KDC Method

Pure K2Ti4O9 whiskers were prepared by KDC（Kneading-Drying-Calcination） method with TiO2 and K2CO3 as raw materials. The influences of TiO2/K2CO3 molar ratio（RT/K）, calcination temperature（TC） and cooling process on phase composition and morphology of the whiskers were investigated by TG-DSC（thermo gravimetric-differential scanning calorimeter）, XRD（X-ray diffraction）, and SEM（scanning electron microscope）. Pure K2Ti4O9 potassium titanate whiskers with large length-diameter ratio（r）（over 250） can be obtained at RT/K = 2.9 and TC = 950 ℃.

Enhanced Loading of ^(40)K from Natural Abundance Potassium Source with a High Performance 2D^+ MOT

40K is one of the most important atomic species for ultra-cold atomic physics. Due to the extremely low con- centration （0.012%） of 40K in natural abundance of potassium, most experiments use 4-10% enriched potassium source, which have greatly suffered from the extremely low annual production and significant price hikes in recent years. Using naturally abundant potassium source, we capture 5.4 × 10 6 cold 40K atoms with the help of a high performance of two-dimensional magneto-optical trap （2D＋ MOT）, which is almost three orders of magnitude greater than previous results without the 2D＋ MOT. The number of the 40K atoms is sufficient for most ultra-cold 40K experiments, and our approach provides an ideal alternative for the field.

Solid–liquid Phase Equilibria in the Aqueous Ternary System Containing Lithium,Potassium,and Sulfate ions at 288.15 K

1 Introduction Salt lakes are widely distributed in the western of China,especially in the area of Qinghai-Xizang(Tibet)Plateau.A series of salt lakes in the Qaidam Basin,located in Qinghai Province,China,is famous for their abundance of lithium,potassium and boron resources(Zheng et al,1988;Deng et al,2012).It is well known that the

Potassium forms in calcareous soils as affected by clay minerals and soil development in Kohgiluyeh and Boyer-Ahmad Province,Southwest Iran

Potassium（K） is known as one of the essential nutrients for the growth of plant species. The relationship between K and clay minerals can be used to understand the K cycling, and assess the plant uptake and potential of soil K fertility. This study was conducted to analyze the K forms（soluble, exchangeable, non-exchangeable and structural） and the relationship of K forms with clay minerals of calcareous soils in Kohgiluyeh and Boyer-Ahmad Province, Southwest Iran. The climate is hotter and drier in the west and south of the province than in the east and north of the province. A total of 54 pedons were dug in the study area and 32 representative pedons were selected. The studied pedons were mostly located on calcareous deposits. The soils in the study area can be classified into 5 orders including Entisols, Inceptisols, Mollisols, Alfisols and Vertisols. The main soil clay minerals in the west and south of the study area were illite, chlorite and palygorskite, whereas they were smectite, vermiculite and illite in the north and east of the province. Due to large amount of smectite and high content of organic carbon in soil surface, the exchangeable K in surface soils was higher than that in subsurface soils. It seems that organic matter plays a more important role than smectite mineral in retaining exchangeable K in the studied soils. Non-exchangeable K exhibited close relationships with clay content, illite, vermiculite and smectite. Although the amount of illite was the same in almost all pedons, amounts of structural and non-exchangeable K were higher in humid regions than in arid and semi-arid regions. This difference may be related to the poor reservoir of K~＋ minerals like palygorskite and chlorite together with illite in arid and semi-arid regions. In humid areas, illite was accompanied by vermiculite and smectite as the K~＋ reservoir. Moreover, the mean cumulative non-exchangeable K released by CaCl_2 was higher than that released by oxalic acid, which may be due to the high buffering capacity resulting from high carbonates in soils.

磷酸钾镁水泥水化产物K型鸟粪石稳定性研究

磷酸钾镁水泥是一种凝结硬化快、黏结强度高且环境适应性广的新型胶凝材料,广泛应用于工程快速加固、快速修补和国防建设及有害物质固化等方面。K型鸟粪石是磷酸钾镁水泥主要水化产物,是强度的主要来源,K型鸟粪石的热稳定性对于磷酸钾镁水泥在面临各种复杂环境时更好发挥各项优势具有重要的影响。采用溶解-沉淀法合成高纯度的K型鸟粪石,利用X射线衍射(XRD)、热重分析(TG/DSC)、红外光谱分析(FTIR)等方法研究了温度对K型鸟粪石稳定性的影响规律。结果表明:经50~110℃低温加热后K型鸟粪石有不同程度的损失,50℃时损失较少,110℃时物相已完全被破坏。

钾长石混盐焙烧-浸出提钾过程研究

中国钾盐资源匮乏,而钾长石是一种重要的钾赋存形式。然而,钾长石的开发技术难度大、成本高,至今尚未实现工业化应用。为了解决钾长石开发利用过程中钾提取温度高、浸出率低等问题,该研究选取了贵州铜仁地区钾长石矿为研究对象,探究了钾长石-硫酸钠-碳酸钙混盐的焙烧-浸出过程,考察了钾长石-硫酸钠-碳酸钙的焙烧配比、焙烧温度、焙烧时间、浸取剂浓度等因素对钾长石中钾元素浸出率的影响。实验结果显示,在焙烧体系均匀混合、焙烧温度为800~900℃、焙烧时间为1 h、m(钾长石)∶m(硫酸钠)∶m(碳酸钙)为(1∶1∶6)^(1∶1∶8)条件下,以质量分数为5%NaOH溶液作为浸取液,钾的浸出率可高达99.79%。该研究提供了一条提高钾长石资源利用效率、解决钾盐资源供应问题的新途径,并为相关工业生产提供了有力的技术支持。

我国籽实和饲草燕麦土壤钾素丰缺指标与推荐施钾量初步研究

为了给我国燕麦测土施钾提供科学依据,本研究采用“零散实验数据整合法”和“养分平衡-地力差减法新应用公式”,开展了我国燕麦土壤钾素丰缺指标与推荐施钾量研究。结果表明,我国燕麦土壤速效钾第1~3级丰缺指标依次为≥258、117~258和<117mg/kg,全钾第1~4级丰缺指标依次为≥31、21~31、11~21和<11 g/kg。当钾肥当季利用率40%~60%时,目标产量1.5~6.0t/hm^(2)籽实燕麦第1~4级土壤推荐施钾量分别为0、10~60、20~120和30~180kg/hm^(2);目标产量4.5~15t/hm^(2)饲草燕麦第1~4级土壤推荐施钾量依次为0、18~90、36~180和54~270kg/hm^(2)。本研究初步建立了我国籽实和饲草燕麦土壤钾素丰缺指标推荐施肥系统,为我国燕麦测土施钾奠定了科学基础。

缙云山森林土壤速效K的分布特征及其与物种多样性的关系

The distribution characteristics of soil available K and its correlations with plant species diversity in the forest ecosystem of Mt.Jinyun are studied in this paper.The results are as follows:①Except for shrub-grassland,the content of available K in soil profiles under different communities has an evident gradient,i.e.,A(humus horizon)>B(deposited horizon)>C(parent material horizon).②The content of available K in A and B horizons gradually increases along the successional direction,i.e.,shrub-grassland<Pinus massoniana pure forest<P.massoniana-Symplocos setchuensis mixed forest<evergreen broadleaved forest.This law does not exist in the C horizons.③Different degrees of correlations exist between the content of soil available K and plant species diversity.The correlation between species diversities of trees and grasses and the content of available K in A and B horizons is the most significant.

硝态N累积与菠菜有机N形成及P、K吸收的关系

在低N(0.3g·kg-1土)和高N(0.6g·kg-1土)2个水平下,采用土壤盆栽试验,研究了30个菠菜品种硝态N累积情况及其与植株生长,有机N形成,P、K吸收的关系。结果表明:施N水平低时,30个菠菜品种的硝态N含量与生长量、有机N总量和P、K吸收量之间均无显著的相关关系;高N时,菠菜品种间硝态N含量表现出显著的差异,硝态N含量最高与最低相差242mg·kg-1,与生长量、有机N总量和P、K吸收量之间亦呈极显著正相关关系。

基于LS-SVM建模方法近红外光谱检测土壤速效N和速效K的研究

应用可见/短波近红外光谱(Vis/SW-NIRS)测量土壤速效氮(N)和速效钾(K)含量。光谱预处理包括标准正态变换(SNV),多元散射校正(MSC)和Savitzky Golay平滑结合一阶导数,以消除系统噪声和外部干扰,分别应用偏最小二乘(PLS)和最小二乘支持向量机(LS-SVM)方法建立校正模型。最小二乘支持向量机(LS-SVM)输入分别包括主成分分析得到的主成分(PCs)和PLSR建模得到的潜在变量(LVs)和由PLSR模型回归系数得到有效波长(EWs)。结果表明,三种输入的LS-SVM模型都优于PLS模型,其中EWs-LS-SVM模型最佳,速效氮(N)的相关系数(R2)和预测均方误差RMSEP分别0.82和17.2,速效钾(K)为0.72和15.0。结果表明,利用可见光和短波近红外光谱(Vis/SW-近红外光谱)(325～1 075nm)的LS-SVM的结合,可以作为一个精确的土壤理化性质的测定方法。

盐胁迫下调控玉米胞内Na^(+)/K^(+)比稳定的主要机制与措施

土壤盐渍化显著抑制玉米生长,降低产量。随着盐渍化土壤面积的不断增加,提高玉米耐盐性是育种工作者面临的重要课题。盐害产生的主要变化是Na^(+)富集造成的离子毒害,Na^(+)不断积累导致K^(+)含量呈减少趋势,Na^(+)/K^(+)比是衡量盐害程度的重要指标,维持适宜Na^(+)/K^(+)比是缓解盐胁迫的关键。本文综述了盐胁迫对玉米生长发育的影响、玉米响应盐胁迫的生理生化和分子机制以及玉米维持低Na^(+)/K^(+)比的信号转导与应答机制,这可为后续玉米响应盐胁迫分子机制的深入研究提供支撑。

水液相下两性α丙氨酸K+配合物旋光异构的理论研究

采用密度泛函理论的M06-2X方法,结合自洽反应场理论的SMD模型方法,研究了水液相下两性S型α丙氨酸与一价钾离子配合物(S-α-Ala·K^(+))的旋光异构.反应通道研究发现:S-α-Ala·K^(+)旋光异构反应有a、b和c 3个通道,a是质子只以羰基氧为桥迁移;b是α氢迁移到羰基氧后,质子再从质子化氨基向α碳迁移;c是质子从质子化氨基迁移到羰基氧后,再以氨基氮为桥迁移.势能面计算表明:隐性溶剂效应下,c通道具有优势,决速步能垒是241.7 kJ·mol^(-1);a和b通道为劣势通道,具有共同的决速步能垒261.3 kJ·mol^(-1).显性溶剂效应下,a、b和c 3个通道的决速步能垒基本相同,大约在136.6至142.0 kJ·mol^(-1)之间.结果表明:水液相下S-α-Ala·K^(+)的旋光异构反应进行的极其缓慢,生命体利用S-α-Ala·K^(+)同补K^(+)和丙氨酸具有较好的安全性.

甲醛-酸性铬蓝K-溴酸钾体系催化动力学光度法测定痕量甲醛

基于在硫酸介质中,痕量甲醛对溴酸钾氧化酸性铬蓝K褪色反应有催化作用,且催化褪色程度与溶液中甲醛量在一定范围内成正比,建立了测定痕量甲醛的动力学光度法。讨论了反应介质、试剂用量、反应温度、反应时间及共存离子的影响,建立了最佳反应条件。测定催化反应的表现活化能为1·78kJ/mol。在选定的条件下,方法的线性范围为0·0041～0·20μg/mL,检出限为4·6×10-10g/mL。利用此法测定了废水和空气中的痕量甲醛,RSD小于2·50%(n=5),回收率在98%～99%之间。

钌(Ⅲ)催化溴酸钾氧化酸性铬蓝K动力学光度法测定痕量钌(Ⅲ)(英文)

在100℃，0．16mol／LH3PO4介质中，痕量钌（Ⅲ）催化KBrO3氧化酸性铬蓝K（ACBK）发生褪色反应，于524nm处测定吸光度降低值以监控ACBK的催化反应过程，基于此原理建立了测定痕量钌（Ⅲ）的动力学光度法。该方法对钌（Ⅲ）的检出限为5．03×10^-3νg／L，校准曲线的线性范围为0～0．80vg／L，低于10倍钌（Ⅲ）浓度的共存离子不干扰测定。方法成功应用于矿石和冶金产品中痕量钌（Ⅲ）的测定，相对标准偏差（RSD）为2．8％～4．0％，加标回收率为99．0％～103．0％。