棉花幼苗钾吸收的系统反馈调节初步研究

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王晔, 田晓莉. 棉花幼苗钾吸收的系统反馈调节初步研究. 作物学报, 2013, 39(10): 1843-1848
[WANG Ye, TIAN Xiao-Li. Systemic Feedback Regulation of K⁺ Uptake in Cotton at Seedling Stage . Acta Agronomica Sinica, 2013, 39(10): 1843-1848] 复制到剪切板

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棉花幼苗钾吸收的系统反馈调节初步研究

王晔, 田晓莉^*

中国农业大学作物化学控制研究中心 / 植物生理学与生物化学国家重点实验室, 北京 100193

^*通讯作者(Corresponding author): 田晓莉, E-mail:tianxl@cau.edu.cn, Tel: 010-62732039

收稿日期:2013-06-09

基金:本研究由中央高校基本科研业务费专项(2013BH023), 国家自然科学基金项目(31271629)和中国博士后科学基金项目(2013M530776)资助。

摘要

以中棉所41和辽棉17为材料, 采用单接穗双砧木嫁接的方法构建分根体系, 在营养液培养条件下研究棉花幼苗钾吸收的系统反馈调节。分根处理6 d后, 高钾侧(2.50 mmol L^-1)根系(Sp.+K)的吸收能力受到低钾侧(0.01 mmol L^-1) K⁺需求信号的诱导, 吸收动力学参数I_max(最大吸收速率)与整根高钾对照(C.+K)相比增加了79%~92%; 低钾侧根系(Sp.-K)的I_max则受到高钾侧K⁺供应信号的抑制, 与整根低钾对照(C.-K)相比下降了27%~40%。中棉所41分根处理3 d后去除低钾侧根系, 保留的高钾侧根系失去K⁺需求信号的诱导, 其I_max下降。棉花幼苗K⁺吸收的这种反馈调节与地上部和根系的K⁺含量关系不大。

关键词: 棉花; 分根; 钾吸收; 反馈调节

Systemic Feedback Regulation of K⁺ Uptake in Cotton at Seedling Stage

WANG Ye, TIAN Xiao-Li^*

State Key Laboratory of Plant Physiology and Biochemistry / Center of Crop Chemical Control, China Agricultural University, Beijing 100193, China

Abstract

This hydroponic split-root experiment was conducted to elucidate the long-distance systemic regulation of K⁺ uptake in cotton (Gossypium hirsutumL.) seedlings with two cotton cultivars CCRI41 and Liaomian17 as materials. Inverted Y grafting (one scion/two rootstocks, hypocotyl-to-hypocotyl) was used to establish split-root plants. The K⁺-uptake characteristics of cotton seedlings were measured by depletion method and described by kinetic parameters,I_max (the maximum rate of uptake),K_m (the external concentration at which the uptake rate is 0.5I_max) andC_min (the external concentration at which no net flux occurs). In relative to the sufficient K⁺ control (both root halves supplied with 2.50 mmol L^-1K⁺), the root half supplied with 2.50 mmol L^-1K⁺ for six days showed 79% to 92% moreI_max owing to the induction of K⁺-demand signal derived from the root half starved with K⁺. Compared with the K⁺ starvation control (both root halves supplied with 0.01 mmol L^-1K⁺),I_max of root half supplied with 0.01 mmol L^-1K⁺ for six days decreased by 27% to 40% due to the suppression of K⁺-supply signal initiated by the root half grown in sufficient K⁺. When the root half starved with K⁺ in CCRI41 was removed after three days of split-root treatment, the remained root half incessantly supplied with 2.50 mmol L^-1K⁺ for six days had lessI_maxrelative to the whole split-root plants, which is likely attributed to the loss of K⁺-demand signal from the other root half during last three days. This systemic feedback regulation of K⁺ uptake in cotton seedlings was independent of K⁺ content of either root or shoot.

Keyword: Cotton; Split-root; K uptake; Systemic regulation

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引言

土壤中矿质养分的有效性处于波动状态, 植物不仅以高效的感应系统(局部信号)感知外部养分浓度的变化, 还以内部系统信号报告各器官的养分状态, 从而精细调节养分的运输和代谢, 使根系的吸收能力与植株需求相匹配^[1,2]。系统信号包括根-冠和冠-根两种长距离信号, 分别传递根系感受到的养分变化信息和地上部的养分需求信息, 冠-根信号又称反馈信号。近20余年来, 养分吸收的局部调节研究在细胞水平和分子水平上取得较快进展^[3,4,5], 但对长距离系统调节仍所知甚少^[6,7]。

K⁺是植物必需的大量营养元素之一, 占植物干重的2%~10%^[8], 在酶的活化、膜运输、阴离子中和及渗透调节等方面发挥重要作用^[9], 并显著影响光合作用和同化产物运输等生理过程, 最终导致植物生长和发育的变化^[10]。棉花属于喜钾作物^[11], 但其根系在耕层和表层土壤的分布比较稀疏^[12,13], 因而对缺钾比较敏感^[14]。K⁺供应不足时棉花发生一系列生理异常^[15], 产量和品质也受到较大影响^[16]。

关于植物K⁺吸收的研究起步较早, 在20世纪90年代之前形成了两种相反的意见。一种认为根系组织的K⁺浓度([K⁺])对K⁺吸收起主要调节作用^[17], 另一种认为地上部是影响K⁺吸收的主要因素^[18,19]。20世纪90年代后, K⁺吸收研究集中在K⁺通道和运输载体的鉴定及细胞水平调控网络的揭示上^[5], 仅有个别报道涉及长距离调控^[20]。本文采用分根和去根等方法研究了棉花K⁺吸收的长距离系统反馈调节现象, 一方面为明确K⁺吸收的系统调节提供试验证据, 另一方面为制定适宜栽培措施缓解棉花的缺钾问题提供理论依据。

1 材料与方法

1.1 试验材料及处理

供试品种中棉所41和辽棉17种子分别由中国农业科学院棉花研究所和辽宁省农业科学院经济作物研究所提供。试验于中国农业大学光照培养室进行, 光照强度为600 μmol cm^-2 s^-1, 光照/黑暗时间为12 h/12 h, 昼/夜温度为(30±2)℃/(22±2)℃, 相对湿度为70%~80%。种子经9%双氧水消毒15~20 min后用流水清洗数遍, 在去离子水中浸种12 h, 露白后播种于不含K⁺的沙床, 出苗2 d后转移至K⁺浓度为2.50 mmol L^-1的1/2改良Hoagland营养液中^[21]。

采用“单接穗双砧木”自身嫁接法^[21]构建分根植株(图1), 嫁接位点位于下胚轴。砧木和接穗在上述营养液中培养5 d, 至第1片真叶出现时嫁接, 嫁接苗在高湿(相对湿度75%左右)、弱光(80 μmol cm^-2 s^-1)环境下缓苗7 d, 后移至600 μmol cm^-2 s^-1光强下培养。

1.2 试验设计

选择生长一致的嫁接棉株, 将2个砧木分别放入相邻的2个用锡箔纸包裹的300 mL玻璃管中(图1), 在2.50 mmol L^-1 K⁺营养液中培养至三叶期开始分根处理。高钾侧(Split-root +K, 简写为Sp.+K)K⁺浓度为2.50 mmol L^-1, 低钾侧(Split-root -K, 简写为Sp.-K)K⁺浓度为0.01 mmol L^-1, 并分别设高钾对照(Control +K, 简写为C.+K, 两侧K⁺浓度均为2.5 mmol L^-1)和缺钾对照(Control -K, 简写为C.-K, 两侧K⁺浓度均为0.01 mmol L^-1), 处理6 d后取样。

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	图1 单接穗双砧木分根系统Fig. 1 Split-root plant of one scion/two rootstocks

此外, 中棉所41在分根处理的基础上开展去根试验, 即在分根处理3 d后剪除Sp.-K侧根系, Sp.+K侧则正常供K⁺, 继续培养3 d后取样, 该处理表示为Remove the split-root-K, 简写为Re.Sp.-K。每处理重复3次, 每天更换一次营养液, 24 h通气。

1.3 取样及测定

1.3.1 干重和钾含量用去离子水反复冲洗根系, 然后将植株在嫁接位点处分为接穗和2个砧木共三部分, 置105℃鼓风干燥箱杀青15 min, 在80℃下烘至恒重后记录重量。将烘干样品研成粉末, 用1 mol L^-1 HCl振荡浸提8 h, 采用原子吸收分光光度计(SpectAA-50/55, Varian, Australia)测定滤液的钾浓度。

1.3.2 K⁺吸收动力学参数测定将各处理植株先在含0.2 mmol L^-1 CaSO₄、pH为5.7的饥饿液中饥饿24 h(每12 h换一次饥饿液), 然后用去离子水冲洗根系, 将2个砧木分别移入用锡箔纸包裹并盛有250 mL耗竭液的2个相邻玻璃瓶中(图1), 每瓶2株, 重复3次。耗竭液起始K⁺浓度为0.25 mmol L^-1, 分别于5、15、25、40、70、100、130、160、190、250、310、370、490、610、670、730、850、970、1150、1330、1690和1930 min取耗竭液, 每次吸取1 mL, 同时补充1 mL原始耗竭液。测定各次所取耗竭液的K⁺浓度, 绘制K⁺耗竭曲线。根据蒋廷惠等^[22]的方法计算K⁺最大吸收速率( I_max)、根系对离子的亲和常数( K_m)和吸收速率为零时的外界钾离子浓度( C_min)。

1.4 数据统计

各试验均独立重复3次以上, 各次结果趋势一致, 文中所用数据为其中具有代表性的一次。用SAS统计软件(V8, SAS Institute Inc., Cary, USA)的ANOVA法进行差异显著性分析( P=0.05), 用Duncan’s法进行多重比较。

2 结果与分析

2.1 干物重和钾含量

表1结果显示, 两品种C. -K的生长及钾含量显著低于C.+K, 其中中棉所41地上部干重和钾含量分别降低40%和14%, 根系干重和钾含量分别降低24%和20%; 辽棉17地上部干重和钾含量分别降低33%和8.5%, 根系干重和钾含量分别降低21%和18%。两品种Sp.+K-K的地上部干重和钾含量显著高于C.-K(辽棉17钾含量除外), 与C.+K相比有降低趋势但差异不显著(中棉所41钾含量除外), 说明局部根系供K⁺在短时间内(6 d)基本可满足棉株正常生长的需要。两品种Sp.+K侧的根系干重和钾含量低于C.+K, Sp.-K侧的根系干重和钾含量高于C.-K, Sp.+K侧有高于Sp.-K侧的趋势, 但这些差异均不显著。

中棉所41分根处理3 d后去除Sp.-K侧根系(Re.Sp.-K), 继续培养3 d, 发现地上部干重和钾含量较Sp.+K-K有所增加, 但差异未达显著水平; 保留的高钾侧根系[Sp.+K (Re.Sp.-K)]的干重和钾含量也较Sp.+K增加, 其中干重差异达到显著水平, 与C.+K基本相当。

表1 棉花分根幼苗(两侧均等或非均等供K⁺)地上部和根系的干重及钾含量 Table 1 Dry weight and K⁺ concentration of both shoot and root of cotton split-root seedlings

表2 棉花分根幼苗(两侧均等或非均等供K⁺)的K⁺吸收动力学参数 Table 2 Kinetic parameter of K⁺-uptake in cotton split-root seedlings

2.2 根系K⁺吸收动力学参数

从表2可以看出, 低钾对照(C.-K)的根系吸K⁺能力显著高于高钾对照(C.+K)。中棉所41和辽棉17 C.-K的 I_max较C.+K分别高2.9倍和2.4倍, K_m较后者分别低51%和33%, C_min仅相当于后者的8%和26%。分根处理6 d后, 中棉所41和辽棉17 Sp.+K侧根系的 I_max与C.+K相比分别显著提高92%和79%, Sp. -K侧根系的 I_max与C.-K相比则分别降低26%和40%; 两品种Sp.-K侧的 I_max均高于Sp.+K侧, 但差异不显著。Sp.+K侧根系的 K_m和 C_min与C.+K相比显著降低了17%~29%和38%~49%, Sp.-K侧根系的 K_m和 C_min与C.-K相比显著增加了34%~41%和216%~531%; 两侧的 K_m和 C_min无显著差异。

中棉所41分根处理3 d后去除Sp.-K侧根系, 保留的Sp.+K侧根系[Sp.+K(Re.Sp.-K)]的吸K⁺能力在继续培养3 d后较Sp.+K (不去除Sp.-K侧根系)下降, 基本恢复到C.+K的水平, 其中 I_max虽然仍较C.+K高50%但差异不显著, K_m和 C_min则与C.+K相当。

3 讨论

绝大多数研究证明, 矿质养分吸收的长距离反馈调节现象普遍存在。拟南芥分根植株一侧根系处于NO₃^-饥饿状态时, 另一侧根系(供应NO₃^-)的NO₃^-内流速率和At NRT2.1 (编码高亲和NO₃^-运输载体)转录丰度上调^[23]。将分根试验与转录谱检测相结合, 发现蒺藜苜蓿NO₃^-和NH₄⁺的吸收及根瘤N₂的固定均受到系统反馈调节, 且每一种N源都有其特异的系统调控网络^[24]。植株对Pi的需求通过供Pi部分根系得到满足后, 缺Pi部分根系Pi转运蛋白的表达不再受低Pi诱导^[25,26,27]。植物的部分根系处于缺Fe条件下时, 可诱导另一部分供Fe根系的Fe(III)还原酶活性和/或质子分泌增强^[28,29,30]。

Claassen和Barber^[18]及Drew和Saker^[19]的早期分根试验证明, K⁺吸收能力也受到地上部的反馈调节。分根处理10 d, 玉米幼苗供K⁺部分根系的K⁺内流速率较整根供K⁺增加2.6倍^[18]; 大麦分根处理3~4 d, 供K⁺部分根系⁴²K和⁸⁶Rb的吸收速率较整根供K⁺提高近一倍^[19]。但近期的胡椒分根试验表明, 处理3 d后缺K⁺侧根系的高亲和K⁺吸收与供K⁺侧的K⁺状况无关, 提示地上部调节高亲和K⁺吸收的可能性不大^[20]。本试验棉花幼苗分根处理6 d, 高K⁺侧根系(Sp.+K)的 I_max在低K⁺侧(Sp.-K)发出的缺K⁺信号诱导下较高钾对照(C.+K)增加79%~92%; Sp.-K侧根系的 I_max在高K⁺侧(Sp.+K)发出的供K⁺信号作用下较低钾对照(C.-K)降低26%~40%; 分根处理3 d后去除缺钾感应器官Sp.-K侧根系, 再经过3 d后Sp.+K侧根系的 I_max虽然仍高于C.+K但差异不显著, K_m和 C_min则恢复到C.+K的水平。这些结果为棉花幼苗K⁺吸收的反馈调节提供了可靠的证据, 支持早期的研究结果^[18,19]。

最近, Ruffel等^[31]的拟南芥分根试验显示, 植物至少存在两种遗传上独立的系统信号, 分别报告植株的N供应和N需求状况。分根处理供N侧的侧根长度大于高N对照, 他们认为这是长距离N-需求信号(由缺N侧发出)和局部NO₃^-供应共同作用的结果; 分根处理缺N侧的侧根长度小于缺N对照, 则可能与供N侧发出的N-供应信号(抑制信号)有关。本试验结果表明, 分根处理Sp.+K根系的 I_max较C.+K增加了79%~92%, 而Sp.-K根系的 I_max较C.-K仅下降27%~40%。我们推测, Sp.-K侧根系发出的K⁺-需求信号较强, 因而Sp.+K侧根系的吸收速率得到较大提升; 来自Sp.+K侧的K⁺-供应信号较弱, 所以Sp.-K侧根系的 I_max变化较小。与 I_max相反, 分根处理Sp.+K侧 K_m和 C_min与C.+K的差异小于Sp.-K侧根系与C.-K的差异(Sp.+K侧的 K_m和 C_min值较C.+K分别下降17%~29%和38%~49%, 而Sp.-K侧根系的 K_m和 C_min值较C.-K分别增加34%~41%和216%~ 528%), 提示棉花根系K⁺通道/运输载体的数量与亲和性可能受不同系统信号的调节。

由于不同物种根系中的[K⁺]与K⁺内流速率呈相反关系, 早期研究认为根系细胞[K⁺](可能是细胞质中的[K⁺])对K⁺内流进行负反馈变构调节^{[17,32,33,34,35]}。Claassen和Barber^[18]的结果则相反, 他们将分根试验与K⁺浓度梯度试验、K⁺饥饿不同时间试验的数据综合起来计算, 发现地上部[K⁺]较根系[K⁺]与K⁺最大吸收速率( I_max)的关系更为密切, R²达到0.74。然而, 此后细胞水平和分子水平上的研究既未明确根系细胞中的K⁺在调控K⁺通道/运输载体表达中有何作用^[5], 也未进一步揭示地上部K⁺调控根系吸收能力的生理机制。本试验中棉所41分根处理Sp.+K侧的 I_max较C.+K提高92%, 但该侧根系和地上部的[K⁺]较后者仅分别降低10%和6%; 辽棉17分根处理Sp.+K侧的 I_max较C.+K提高79%, 但该侧根系和地上部的[K⁺]与后者基本相当。这些结果表明, 根系和地上部的K⁺未直接参与K⁺吸收的调控。

与局部供N和供Pi不同, 根系在局部供K⁺条件下不发生明显的补偿生长^[36,37,38]。与此一致, 本试验分根处理Sp.+K侧根系的干重低于或显著低于C.+K两侧的平均值, 与Sp.-K侧根系基本相当, 未表现出补偿生长现象。De Jager^[39]和Ma等^[40]的结果则相反, 他们发现局部供K⁺对根系生长的刺激效应分别与局部供NO₃^-和Pi相当, 但前提是缺K⁺部分完全不供K⁺或长时间分根处理后地上部的[K⁺]明显降至最适状态以下。本试验分根处理Sp.-K侧的供K⁺浓度为0.01 mmol L^-1, 处理结束时(持续6 d)地上部的[K⁺]与C.-K均处于较高水平(30 mg g^-1左右)。如果延长棉花幼苗分根处理时间, 或将Sp.-K侧的供K⁺浓度降为0, Sp.+K侧根系是否会出现补偿生长则未可知。

4 结论

分根处理后高钾侧(2.50 mmol L^-1)根系受到低钾侧(0.01 mmol L^-1) K⁺需求信号的诱导其 I_max较高钾对照增加, 低钾侧根系则受到高钾侧K⁺供应信号的抑制其 I_max较低钾对照降低; 去除低钾侧根系, 保留的高钾侧根系因失去K⁺需求信号的诱导其 I_max较完整分根植株有所下降。根系和地上部组织的[K⁺]与K⁺吸收的这种系统反馈调节没有直接关系。

The authors have declared that no competing interests exist.

作者已声明无竞争性利益关系。

参考文献

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[1]	Alvarez J M, Vidal E A, Gutierrez R A. . Integration of local and systemic signaling pathways for plant N responses. Curr Opin Plant Biol, 2012, 15: 185-191 [本文引用:1] [JCR: 9.272]
[2]	Lough T J, Lucas W J. . Integrative plant biology: role of phloem long-distance macromolecular trafficking. Annu Rev Plant Biol, 2006, 57: 203-232 [本文引用:1] [JCR: 25.962]
[3]	Ho C H, Lin S H, Hu H C, Tsay Y F. . CHL1 functions as a nitrate sensor in plants. Cell, 2009, 138: 1184-1194 [本文引用:1] [JCR: 32.403]
[4]	Chiou T J, Lin S I. . Signaling network in sensing phosphate availability in plants. Annu Rev Plant Biol, 2011, 62: 185-206 [本文引用:1] [JCR: 25.962]
[5]	Wang Y, Wu W H. . Potassium transport and signaling in higher plants. Annu Rev Plant Biol, 2013, 64: 4. 1-4. 26 [本文引用:3] [JCR: 25.962]
[6]	Schmidt W, Michalke W, Schikora A. . Proton pumping by tomato roots: effect of Fe deficiency and hormones on the activity and distribution of plasma membrane H⁺-ATPase in thizodermal cells. Plant Cell Environ, 2003, 26: 361-370 [本文引用:1] [JCR: 5.215]
[7]	Liu T Y, Chang C Y, Lin T J. . The long-distance signaling of mineral macro-nutrients. Curr Opin Plant Biol, 2009, 12: 312-319 [本文引用:1] [JCR: 9.272]
[8]	Leigh R A, Wyn Jones R G. . A hypothesis relating critical potassium concentrations for growth to the distribution and functions of this ion in the plant cell. New Phytol, 1984, 97: 1-13 [本文引用:1] [JCR: 6.645]
[9]	Clarkson D T, Hanson J B. . The mineral nutrition of higher plants. Annu Rev Plant Physiol, 1980, 31: 239-298 [本文引用:1]
[10]	Maathuis F J M. . Physiological functions of mineral macronutrients. Curr Opin Plant Biol, 2009, 12: 250-258 [本文引用:1] [JCR: 9.272]
[11]	Kerby T A, Adams F. . Potassium nutrition of cotton Gossypium hirsutum. In: Munson R D ed. Potassium in Agriculture International Symposium. Atlanta GA USA, 1985. pp843-860 [本文引用:1]
[12]	Gerik T J, Morrison J E, Chichester F W. . Effects of controlled-traffic on soil physical properties and crop rooting. Agron J, 1987, 79: 434-438 [本文引用:1] [JCR: 1.794]
[13]	Brouder S M, Cassman K G. . Cotton root and shoot response to localized supply of nitrate, phosphate and potassium: split-pot studies with nutrient solution and vermiculitic soil. Plant Soil, 1994, 161: 179-193 [本文引用:1] [JCR: 2.733]
[14]	Cope J T. . Effects of 50 years of fertilization with phosphorus and potassium on soil test levels and yields at six locations. Soil Sci Soc Am J, 1981, 45: 342-347 [本文引用:1] [JCR: 1.979]
[15]	Dong H-Z(董合忠), Li W-J(李维江), Tang W(唐薇), Zhang D-M(张冬梅). . Research progress in physiological premature senescence in cotton. Cotton Sci(棉花学报), 2005, 17: 56-60 (in Chinese with English abstract) [本文引用:1] [CJCR: 1.4495]
[16]	Pettigrew W T, Meredith Jr W R. . Dry matter production, nutrient uptake, and growth of cotton as affected by potassium fertilization. J Plant Nutr, 1997, 20: 531-548 [本文引用:1] [JCR: 0.641]
[17]	Siddiqi M Y, Glass A D M. . Regulation of K⁺ influx in barley: Evidence for a direct control of influx by K⁺ concentration of root cells. J Exp Bot, 1987, 38: 935-947 [本文引用:2] [JCR: 5.364]
[18]	Claassen N, Barber S A. . Potassium influx characteristics of corn roots and interaction with N, P, Ca, and Mg influx. Agron J, 1977, 69: 860-864 [本文引用:5] [JCR: 1.794]
[19]	Drew M C, Saker L R. . Uptake and long-distance transport of phosphate, potassium and chloride in relation to internal ion concentrations in barley: evidence of non-allosteric regulation. Planta, 1984, 160: 500-507 [本文引用:4] [JCR: 3.0]
[20]	Martinez-Cordero M A, Martinez V, Rubio F. . High-affinity K⁺ uptake in pepper plants. J Exp Bot, 2005, 56: 1553-1562 [本文引用:2] [JCR: 5.364]
[21]	Li B(李博), Wang C-X(王春霞), Zhang Z-Y(张志勇), Duan L-S(段留生), Li Z-H(李召虎), Tian X-L(田晓莉). . Three types of grafting techniques available for research of root-shoot communication in cotton (Gossypium hirsutum) seedlings under low- potassium condition. Acta Agron Sin(作物学报), 2009, 35(2): 363-369 (in Chinese with English abstract) [本文引用:2] [CJCR: 1.8267]
[22]	Jiang T-H(蒋廷惠), Zheng S-J(郑绍建), Shi J-Q(石锦芹), Hu A-T(胡霭堂), Shi R-H(史瑞和), Xu M(徐茂). . Several considerations in kinetic research on nutrients uptake by plants. Plant Nutr Fert Sci(植物营养与肥料学报), 1995, 1(2): 11-17 (in Chinese with English abstract) [本文引用:1] [CJCR: 1.4752]
[23]	Gansel X, Munos S, Tillard P, Gojon A. . Differential regulation of the NO₃^- and NH₄⁺ transporter genes AtNRT2. 1 and AtMR1. 1 in Arabidopsis: relation with long-distance and local controls by N status of the plant. Plant J, 2001, 26: 143-155 [本文引用:1] [JCR: 6.16]
[24]	Ruffel S, Freixes S, Balzergue S, Tillard P, Jeudy C, Martin- Magniette M L, van der Merwe M J, Kakar K, Gouzy J, Fernie A R, Udvardi M, Salon C, Gojon A, Lepetit M. . Systemic signaling of the plant nitrogen status triggers specific transcriptome responses depending on the nitrogen source in Medicago truncatula. Plant Physiol, 2008, 146: 2020-2035 [本文引用:1] [JCR: 6.535]
[25]	Liu C, Muchhal U S, Uthappa M, Kononowicz A K, Raghothama K G. . Tomato phosphate transporter gene are differentially regulated in plant tissues by phosphorus. Plant Physiol, 1998, 116: 91-99 [本文引用:1] [JCR: 6.535]
[26]	Chiou T J, Liu H, Harrison M J. . The spatial expression patterns of a phosphate transporter (MtPT1) from Medicago truncatula indicate a role in phosphate transport at the root/soil interface. Plant J, 2001, 25: 281-293 [本文引用:1] [JCR: 6.16]
[27]	Smith F W, Mudge S R, Rae A L, Glassop D. . Phosphate transport in plants. Plant Soil, 2003, 248: 71-83 [本文引用:1] [JCR: 2.733]
[28]	Schmidt W, Boomgaarden B, Ahrens V. . Reduction of root iron in Plantagolanceolata during recovery from Fe deficiency. Physiol Plantarum, 1996, 98: 587-593 [本文引用:1] [JCR: 3.112]
[29]	Schikora A, Schmidt W. . Iron stress-induced changes in root epidermal cell fate are regulated independently from physiological responses to low iron availability. Plant Physiol, 2001, 125: 1679-1687 [本文引用:1] [JCR: 6.535]
[30]	Wu T, Zhang H T, Wang Y, Jia W S, Xu X F, Zhang X Z, Han Z H. . Induction of root Fe (III) reductase activity and proton extrusion by iron deficiency is mediated by auxin-based systemic signalling in Malusxiaojinensis. J Exp Bot, 2012, 63: 859-870 [本文引用:1] [JCR: 5.364]
[31]	Ruffel S, Krouk G, Ristova D, Shasha D, Birnbaum K D, Coruzzi G M. . Nitrogen economics of root foraging: Transitive closure of the nitrate-cytokinin relay and distinct systemic signaling for N supply vs. demand . Proc Natl Acad Sci USA, 2011, 108: 18524-18529 [本文引用:1] [JCR: 9.737]
[32]	Glass A D M. . The regulation of potassium absorption of barley roots. Plant Physiol, 1975, 56: 377-380 [本文引用:1] [JCR: 6.535]
[33]	Glass A D M. . Regulation of potassium absorption in barley roots: an allosteric model. Plant Physiol, 1976, 58: 33-37 [本文引用:1] [JCR: 6.535]
[34]	Jensen P, Pettersson S. . Nutrient uptake in roots of scotch pine (Pinussylvestris). In: Persson T ed. Ecological Bulletins No. 32, Structure and Function of Northern Coniferous Forests: an Ecosystem Study, 1980. pp229-237 [本文引用:1]
[35]	Jensen P. . Control of K⁺(Rb⁺) influx and transport with changed internal K⁺ concentration and age in 2 varieties of barley. Physiol Plant, 1980, 49: 291-295 [本文引用:1] [JCR: 6.535]
[36]	Drew M C. . Comparison of the effects of a localized supply of phosphate, nitrate, ammonium and potassium on the growth of the seminal root system, and the shoot, in barley. New Phytol, 1975, 75: 479-490 [本文引用:1] [JCR: 6.645]
[37]	Wiersum L K. . Influence of water-content of sand on rate of uptake of Rubidium-86. Nature, 1958, 181: 106-107 [本文引用:1] [JCR: 36.28]
[38]	Brouder S M, Cassman K G. . Root development of two cotton cultivars in relation to potassium uptake and plant growth in a vermiculite soil. Field Crops Res, 1990, 23: 187-203 [本文引用:1] [JCR: 2.474]
[39]	De Jager A. . Effects of localized supply of acid phosphate nitrate sulfate calcium and potassium on the production and distribution of dry matter in young maize (Zea mays) plants. Neth J Agric Sci, 1982, 30: 193-204 [本文引用:1]
[40]	Ma Q F, Rengel Z, Bowden B. . Heterogeneous distribution of phosphorus and potassium in soil influences wheat growth and nutrient uptake. Plant Soil, 2007, 291: 301-309 [本文引用:1] [JCR: 2.733]

2012

9.272

0.0

Curr. Opin. Plant Biol.. 2012, 15(2):185-91 DOI:10.1016/j.pbi.2012.03.009

Integration of local and systemic signaling pathways for plant N responses.

Alvarez JM, Vidal EA, Gutiérrez RA

FONDAP Center for Genome Regulation, Millennium Nucleus Center for Plant Functional Genomics, Departamento de Genética Molecular y Microbiología, Pontificia Universidad Católica de Chile, Alameda 340, Santiago, Chile.

Nitrogen (N) is an essential macronutrient and a signal that has profound impacts on plant growth and development. In order to cope with changing N regimes in the soil, plants have developed complex regulatory mechanisms that involve short-range and long-range signaling pathways. These pathways act at the cellular and whole plant scale to coordinate plant N metabolism, growth and development according to external and internal N status. Although molecular components of local and systemic N signaling have been identified and characterized, an integrated view of how plants coordinate and organize the N response is still lacking. In this review, we discuss recent advances toward understanding the mechanisms of local and systemic N responses and provide an integrated model for how these responses are orchestrated.

PMID: 22480431

... 引言土壤中矿质养分的有效性处于波动状态, 植物不仅以高效的感应系统(局部信号)感知外部养分浓度的变化, 还以内部系统信号报告各器官的养分状态, 从而精细调节养分的运输和代谢, 使根系的吸收能力与植株需求相匹配^[1,2] ...

2006

25.962

0.0

Annu Rev Plant Biol. 2006, 57:203-32

Integrative plant biology: role of phloem long-distance macromolecular trafficking.

Lough TJ, Lucas WJ

Agrigenesis Biosciences, Auckland, New Zealand. T.Lough@agrigenesis.co.nz

Recent studies have revealed the operation of a long-distance communication network operating within the vascular system of higher plants. The evolutionary development of this network reflects the need to communicate environmental inputs, sensed by mature organs, to meristematic regions of the plant. One consequence of such a long-distance signaling system is that newly forming organs can develop properties optimized for the environment into which they will emerge, mature, and function. The phloem translocation stream of the angiosperms contains, in addition to photosynthate and other small molecules, a variety of macromolecules, including mRNA, small RNA, and proteins. This review highlights recent progress in the characterization of phloem-mediated transport of macromolecules as components of an integrated long-distance signaling network. Attention is focused on the role played by these proteins and RNA species in coordination of developmental programs and the plant's response to both environmental cues and pathogen challenge. Finally, the importance of developing phloem transcriptome and proteomic databases is discussed within the context of advances in plant systems biology.

PMID: 16669761

2009

32.403

0.0

... 近20余年来, 养分吸收的局部调节研究在细胞水平和分子水平上取得较快进展^[3,4,5], 但对长距离系统调节仍所知甚少^[6,7] ...

2011

25.962

0.0

Annu Rev Plant Biol. 2011, 62:185-206 DOI:10.1146/annurev-arplant-042110-103849

Signaling network in sensing phosphate availability in plants.

Chiou TJ, Lin SI

Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan. tjchiou@gate.sinica.edu.tw

Plants acquire phosphorus in the form of phosphate (Pi), the concentration of which is often limited for plant uptake. Plants have developed diverse responses to conserve and remobilize internal Pi and to enhance Pi acquisition to secure them against Pi deficiency. These responses are achieved by the coordination of an elaborate signaling network comprising local and systemic machineries. Recent advances have revealed several important components involved in this network. Pi functions as a signal to report its own availability. miR399 and sugars act as systemic signals to regulate responses occurring in roots. Hormones also play crucial roles in modulating gene expression and in altering root system architecture. Transcription factors function as a hub to perceive the signals and to elicit steady outputs. In this review, we outline the current knowledge on this subject and present hypotheses pertaining to other potential signals and to the organization and coordination of signaling.

PMID: 21370979

... 近20余年来, 养分吸收的局部调节研究在细胞水平和分子水平上取得较快进展^[3,4,5], 但对长距离系统调节仍所知甚少^[6,7] ...

2013

25.962

0.0

... 近20余年来, 养分吸收的局部调节研究在细胞水平和分子水平上取得较快进展^[3,4,5], 但对长距离系统调节仍所知甚少^[6,7] ...

... 20世纪90年代后, K⁺吸收研究集中在K⁺通道和运输载体的鉴定及细胞水平调控网络的揭示上^[5], 仅有个别报道涉及长距离调控^[20] ...

... 然而, 此后细胞水平和分子水平上的研究既未明确根系细胞中的K⁺在调控K⁺通道/运输载体表达中有何作用^[5], 也未进一步揭示地上部K⁺调控根系吸收能力的生理机制 ...

2003

5.215

0.0

... 近20余年来, 养分吸收的局部调节研究在细胞水平和分子水平上取得较快进展^[3,4,5], 但对长距离系统调节仍所知甚少^[6,7] ...

2009

9.272

0.0

Curr Opin Plant Biol. 2009, 12(3):312 - 319 DOI:10.1016/j.pbi.2009.04.004

The long-distance signaling of mineral macronutrients

In response to varying nutrient availability in soil, plants display a high degree of physiological and developmental plasticity that relies on both local and systemic signaling pathways to coordinate the expression of genes involved in adaptive responses. The integration of these responses at the whole-plant level requires long-distance signaling mechanisms communicating the information between the two indispensable organs, the shoot and the root, which respectively provide photosynthates and mineral nutrients. Although such long-distance signaling is not well understood at the molecular level, several molecules, including hormones, sugars, and nutrients themselves or their metabolites, have been suggested to function as the systemic signals. Moreover, recent discoveries of the phloem-mobile microRNA399s as key components mediating the plant responses to phosphorus stress reveal a novel biological role of small RNA in the long-distance signaling of nutrient status.

... 近20余年来, 养分吸收的局部调节研究在细胞水平和分子水平上取得较快进展^[3,4,5], 但对长距离系统调节仍所知甚少^[6,7] ...

1984

6.645

0.0

... K⁺是植物必需的大量营养元素之一, 占植物干重的2%~10%^[8], 在酶的活化、膜运输、阴离子中和及渗透调节等方面发挥重要作用^[9], 并显著影响光合作用和同化产物运输等生理过程, 最终导致植物生长和发育的变化^[10] ...

1980

0.0

2009

9.272

0.0

Curr Opin Plant Biol. 2009, 12(3):250 - 258 DOI:10.1016/j.pbi.2009.04.003

Physiological functions of mineral macronutrients

Plants require calcium, magnesium, nitrogen, phosphorous, potassium and sulfur in relatively large amounts (>0.1% of dry mass) and each of these so-called macronutrients is essential for a plant to complete its life cycle. Normally, these minerals are taken up by plant roots from the soil solution in ionic form with the metals Ca²⁺, Mg²⁺ and K⁺ present as free cations, P and S as their oxyanions phosphate (PO₄³⁻) and sulfate (SO₄²⁻) and N as anionic nitrate (NO₃⁻) or cation ammonium (NH₄⁺).

Recently, important progress has been made in identifying transport and regulatory mechanisms for macronutrients and the mechanisms of uptake and distribution. These and the main physiological roles of each nutrient will be discussed.

1985

0.0

... 棉花属于喜钾作物^[11], 但其根系在耕层和表层土壤的分布比较稀疏^[12,13], 因而对缺钾比较敏感^[14] ...

1987

1.794

0.0

... 棉花属于喜钾作物^[11], 但其根系在耕层和表层土壤的分布比较稀疏^[12,13], 因而对缺钾比较敏感^[14] ...

1994

2.733

0.0

... 棉花属于喜钾作物^[11], 但其根系在耕层和表层土壤的分布比较稀疏^[12,13], 因而对缺钾比较敏感^[14] ...

1981

1.979

0.0

... 棉花属于喜钾作物^[11], 但其根系在耕层和表层土壤的分布比较稀疏^[12,13], 因而对缺钾比较敏感^[14] ...

2005

0.0

1.4495

... K⁺供应不足时棉花发生一系列生理异常^[15], 产量和品质也受到较大影响^[16] ...

1997

0.641

0.0

... K⁺供应不足时棉花发生一系列生理异常^[15], 产量和品质也受到较大影响^[16] ...

1987

5.364

0.0

... 一种认为根系组织的K⁺浓度([K⁺])对K⁺吸收起主要调节作用^[17], 另一种认为地上部是影响K⁺吸收的主要因素^[18,19] ...

... 由于不同物种根系中的[K⁺]与K⁺内流速率呈相反关系, 早期研究认为根系细胞[K⁺](可能是细胞质中的[K⁺])对K⁺内流进行负反馈变构调节^{[17,32,33,34,35]} ...

1977

1.794

0.0

... 一种认为根系组织的K⁺浓度([K⁺])对K⁺吸收起主要调节作用^[17], 另一种认为地上部是影响K⁺吸收的主要因素^[18,19] ...

... Claassen和Barber^[18]及Drew和Saker^[19]的早期分根试验证明, K⁺吸收能力也受到地上部的反馈调节 ...

... 6倍^[18] ...

... 这些结果为棉花幼苗K⁺吸收的反馈调节提供了可靠的证据, 支持早期的研究结果^[18,19] ...

... Claassen和Barber^[18]的结果则相反, 他们将分根试验与K⁺浓度梯度试验、K⁺饥饿不同时间试验的数据综合起来计算, 发现地上部[K⁺]较根系[K⁺]与K⁺最大吸收速率(I_max)的关系更为密切, R²达到0 ...

1984

3.0

0.0

... 一种认为根系组织的K⁺浓度([K⁺])对K⁺吸收起主要调节作用^[17], 另一种认为地上部是影响K⁺吸收的主要因素^[18,19] ...

... Claassen和Barber^[18]及Drew和Saker^[19]的早期分根试验证明, K⁺吸收能力也受到地上部的反馈调节 ...

... 大麦分根处理3~4 d, 供K⁺部分根系⁴²K和⁸⁶Rb的吸收速率较整根供K⁺提高近一倍^[19] ...

... 这些结果为棉花幼苗K⁺吸收的反馈调节提供了可靠的证据, 支持早期的研究结果^[18,19] ...

2005

5.364

0.0

J. Exp. Bot.. 2005, 56(416):1553-62

High-affinity K+ uptake in pepper plants.

Martínez-Cordero MA, Martínez V, Rubio F

Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura-CSIC, Apartado de Correos 164, E-30100 Murcia, Spain.

High-affinity K+ uptake is an essential process for plant nutrition under K+-limiting conditions. The results presented here demonstrate that pepper (Capsicum annuum) plants grown in the absence of NH4+ and starved of K+ show an NH4+-sensitive high-affinity K+ uptake that allows plant roots to deplete external K+ to values below 1 microM. When plants are grown in the presence of NH4+, high-affinity K+ uptake is not inhibited by NH4+. Although NH4+-grown plants deplete external K+ below 1 microM in the absence of NH4+, when 1 mM NH4+ is present they do not deplete external K+ below 10 microM. A K+ transporter of the HAK family, CaHAK1, is very likely mediating the NH4+-sensitive component of the high-affinity K+ uptake in pepper roots. CaHAK1 is strongly induced in the roots that show the NH4+-sensitive high-affinity K+ uptake and its induction is reduced in K+-starved plants grown in the presence of NH4+. The NH4+-insensitive K+ uptake may be mediated by an AKT1-like K+ channel.

PMID: 15809279

... 20世纪90年代后, K⁺吸收研究集中在K⁺通道和运输载体的鉴定及细胞水平调控网络的揭示上^[5], 仅有个别报道涉及长距离调控^[20] ...

... 但近期的胡椒分根试验表明, 处理3 d后缺K⁺侧根系的高亲和K⁺吸收与供K⁺侧的K⁺状况无关, 提示地上部调节高亲和K⁺吸收的可能性不大^[20] ...

2009

0.0

1.8267

Acta Agron Sin. 2009, 35(2):363 - 369 DOI:10.3724/SP.J.1006.2009.00363

Three Types of Grafting Techniques Available for Research of Root-Shoot Communication in Cotton(Gossypium hirsutum) Seedlings under Low-Potassium Condition

适用于低钾条件下棉花苗期根冠通讯研究的三种嫁接方法

LI Bo¹,WANG Chun-Xia¹,ZHANG Zhi-Yong^1,2,DUAN Liu-Sheng¹,LI Zhao-Hu¹,TIAN Xiao-Li^1,*

李博¹;王春霞¹;张志勇^1,2;段留生¹;李召虎¹;田晓莉^1,*

1Center of Crop Chemical Control/Key Laboratory of Crop Cultivation and Farming System/State Key Laboratory of National Plant Physiology and Biochemistry,China Agricultural University Beijing 100193,China;2School of Life Science & Technology, Henan Institute of Science and Technology,Xinxiang 453003,China

Grafting have been widely used to limit the effects of soil and vascular diseases,to increase yield and fruit quality, to induce resistance against low and high temperatures, to enhance nutrient uptake and to study the shoot-root relationship. Up to now, the main objectives of cotton grafts are to propagate somatic regeneratedplants, transgenic plants and rare germplasm materials etc., and almost not come down to the research on long-distance signaling in plant. Recently, premature senescence caused by low potassium (K) has become one of the constraints for high yield and fine quality in cotton production.Before using grafting as a tool to investigate the shoot-root communication during this course, applicable grafting methods should be developed firstly.Therefore, we established normal (one scion and one rootstock), Y-type (two scions and one rootstock) and A-type (one scion and two rootstocks) grafting techniques with cotton seedlings (before one-leaf stage) grown in hydroponic condition. The effects of K⁺ concentration in culture solutions, difference of scion age and rootstock age, different grafting sites and remaining cotyledons of rootstock or not on the survival rate of grafted cotton seedlings were examined. Considering either high survival rate or fast inducement of leaf senescence by low-K after grafting, the following methods wereapplicable for normal and Y-type grafting: the rootstocks emerged (3 d after germination) in sands without K, were transferred to one-half strength modified Hoagland solution containing0.1 mmol L^-1 K⁺ (moderate K deficiency) and cultured for 5 d to just appearance of the 1st true leaf; the scions were grown only in sands for 5 d after sowing with fully expanded cotyledons and grafted in cotyledon node of rootstocks with their two cotyledons remained. For A-type grafting, the applicable procedure was as followings: the scions and rootstocks were all cultured with the same procedure for normal and Y-type graftings, the scion was grafted in the part of 2–3 cmbelow cotyledon node of rootstock. The mean survival rates of normal, Y-type and A-type graftings were more than 95%, 85%, and 90%, respectively. These three types of cotton grafting method were not only available for the research of root-shoot communication, but also for the research of shoot-shoot and root-root signals exchange.

为了满足棉花叶片衰老(以缺钾诱导)过程中根冠通讯研究的需要,在营养液培养条件下探索了棉花子叶期至一叶期幼苗的单接穗单砧木嫁接、双接穗单砧木(Y型)和单接穗双砧木(A型)嫁接技术。通过研究营养液中钾浓度、砧木和接穗的苗龄配合、嫁接部位及砧木保留子叶对嫁接成活率的影响,综合考虑嫁接成活率和成活后用缺钾诱导嫁接苗衰老的速度,确定接穗单砧木嫁接和Y型嫁接的砧木均在不含钾的沙床中出苗后(萌发后3 d)转移至钾浓度为0.1mmol L^-1(中度钾胁迫)的1/2改良Hoagland营养液中培养5 d至第1片真叶出现,接穗在不含钾的沙床中出苗后(萌发后3 d)再生长2 d,采用砧木留子叶法在子叶节处嫁接。A型嫁接的适宜条件和方法为砧木和接穗苗龄(第1片真叶刚出现)相同,嫁接前的培养方法同Y型砧木,嫁接部位在砧木子叶节下2~3 cm处。单接穗单砧木、Y型和A型嫁接的平均成活率分别可达到95%、85%和90%以上。

... 50 mmol L^-1的1/2改良Hoagland营养液中^[21] ...

... 采用“单接穗双砧木”自身嫁接法^[21]构建分根植株(图1), 嫁接位点位于下胚轴 ...

1995

0.0

1.4752

... 根据蒋廷惠等^[22]的方法计算K⁺最大吸收速率(I_max)、根系对离子的亲和常数(K_m)和吸收速率为零时的外界钾离子浓度(C_min) ...

2001

6.16

0.0

Plant J.. 2001, 26(2):143-55

Differential regulation of the NO3- and NH4+ transporter genes AtNrt2.1 and AtAmt1.1 in Arabidopsis: relation with long-distance and local controls by N status of the plant.

Gansel X, Muños S, Tillard P, Gojon A

Biochimie et Physiologie Moléculaire des Plantes, UMR 5004, Agro-M, Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, Université Montpellier II, Place Viala, 34060 Montpellier cedex 1, France.

Regulation of root N uptake by whole-plant signalling of N status was investigated at the molecular level in Arabidopsis thaliana plants through expression analysis of AtNrt2.1 and AtAmt1.1. These two genes encode starvation-induced high-affinity NO3- and NH4+ transporters, respectively. Split-root experiments indicate that AtNrt2.1 expression is controlled by shoot-to-root signals of N demand. Together with 15NO3- influx, the steady-state transcript level of this gene is increased in NO3--fed roots in response to N deprivation of another portion of the root system. Thus AtNrt2.1 is the first identified molecular target of the long-distance signalling informing the roots of the whole plant's N status. In contrast, AtAmt1.1 expression is predominantly dependent on the local N status of the roots, as it is mostly stimulated in the portion of the root system directly experiencing N starvation. The same behaviour was found for NH4+ influx, suggesting that the NH4+ uptake system is much less efficient than the NO3- uptake system, to compensate for a spatial restriction of N availability. Other major differences were found between the regulations of AtNrt2.1 and AtAmt1.1 expression. AtNrt2.1 is strongly upregulated by moderate level of N limitation, while AtAmt1.1 transcript level is markedly increased only under severe N deficiency. Unlike AtNrt2.1, AtAmt1.1 expression is not stimulated in a nitrate reductase-deficient mutant after transfer to NO3- as sole N source, indicating that NO3- per se acts as a signal repressing transcription of AtAmt1.1. These results reveal two fundamentally different types of mechanism involved in the feedback regulation of root N acquisition by the N status of the plant.

PMID: 11389756

... 1 (编码高亲和NO₃^-运输载体)转录丰度上调^[23] ...

2008

6.535

0.0

Plant Physiol.. 2008, 146(4):2020-35 DOI:10.1104/pp.107.115667

Systemic signaling of the plant nitrogen status triggers specific transcriptome responses depending on the nitrogen source in Medicago truncatula.

Ruffel S, Freixes S, Balzergue S, Tillard P, Jeudy C, Martin-Magniette ML, van der Merwe MJ, Kakar K, Gouzy J, Fernie AR, Udvardi M, Salon C, Gojon A, Lepetit M

Biochimie et Physiologie Moléculaire des Plantes, UMR 5004, INRA-CNRS-Sup Agro-UM2, Institut de Biologie Intégrative des Plantes, F-34060 Montpellier, France.

Legumes can acquire nitrogen (N) from NO(3)(-), NH(4)(+), and N(2) (through symbiosis with Rhizobium bacteria); however, the mechanisms by which uptake and assimilation of these N forms are coordinately regulated to match the N demand of the plant are currently unknown. Here, we find by use of the split-root approach in Medicago truncatula plants that NO(3)(-) uptake, NH(4)(+) uptake, and N(2) fixation are under general control by systemic signaling of plant N status. Indeed, irrespective of the nature of the N source, N acquisition by one side of the root system is repressed by high N supply to the other side. Transcriptome analysis facilitated the identification of over 3,000 genes that were regulated by systemic signaling of the plant N status. However, detailed scrutiny of the data revealed that the observation of differential gene expression was highly dependent on the N source. Localized N starvation results, in the unstarved roots of the same plant, in a strong compensatory up-regulation of NO(3)(-) uptake but not of either NH(4)(+) uptake or N(2) fixation. This indicates that the three N acquisition pathways do not always respond similarly to a change in plant N status. When taken together, these data indicate that although systemic signals of N status control root N acquisition, the regulatory gene networks targeted by these signals, as well as the functional response of the N acquisition systems, are predominantly determined by the nature of the N source.

PMID: 18287487

... 将分根试验与转录谱检测相结合, 发现蒺藜苜蓿NO₃^-和NH₄⁺的吸收及根瘤N₂的固定均受到系统反馈调节, 且每一种N源都有其特异的系统调控网络^[24] ...

1998

6.535

0.0

... 植株对Pi的需求通过供Pi部分根系得到满足后, 缺Pi部分根系Pi转运蛋白的表达不再受低Pi诱导^[25,26,27] ...

2001

6.16

0.0

... 植株对Pi的需求通过供Pi部分根系得到满足后, 缺Pi部分根系Pi转运蛋白的表达不再受低Pi诱导^[25,26,27] ...

2003

2.733

0.0

Plant Soil. 2003, 248(1-2):71 - 83 DOI:10.1023/A:1022376332180

Phosphate transport in plants

Frank W. Smith(1) Stephen R. Mudge(1) Anne L. Rae(1) Donna Glassop(1)

1.Long Pocket Laboratories CSIRO Plant Industry 120 Meiers Rd Indooroopilly Qld 4068 Australia

Transport of inorganic phosphate (P_i) through plant membranes is mediated by a number of families of transporter proteins. Studies on the topology, function, regulation and sites of expression of the genes that encode the members of these transporter families are enabling roles to be ascribed to each of them. The Pht1 family, of which there are nine members in theArabidopsis genome, includes proteins involved in the uptake of P_i from the soil solution and the redistribution of P_i within the plant. Members of this family are H₂PO₄^–/H⁺ symporters. Most of the genes of the Pht1 family that are expressed in roots are up-regulated in P-stressed plants. Two members of the Pht1 family have been isolated from the cluster roots of white lupin. These same genes are expressed in non-cluster roots. The evidence available to date suggests that there are no major differences between the types of transport systems that cluster roots and non-cluster roots use to acquire P_i. Differences in uptake rates between cluster and non-cluster roots can be ascribed to more high-affinity P_i transporters in the plasma membranes of cluster roots, rather than any difference in the characteristics of the transporters. The efficient acquisition of P_i by cluster roots arises primarily from their capacity to increase the availability of soil P_i immediately adjacent to the rootlets by excretion of carboxylates, protons and phosphatases within the cluster. This paper reviews P_i transport processes, concentrating on those mediated by the Pht1 family of transporters, and attempts to relate those processes involved in P_i acquisition to likely P_i transport processes in cluster roots.

... 植株对Pi的需求通过供Pi部分根系得到满足后, 缺Pi部分根系Pi转运蛋白的表达不再受低Pi诱导^[25,26,27] ...

1996

3.112

0.0

... 植物的部分根系处于缺Fe条件下时, 可诱导另一部分供Fe根系的Fe(III)还原酶活性和/或质子分泌增强^[28,29,30] ...

2001

6.535

0.0

Plant Physiol.. 2001, 125(4):1679-87

Iron stress-induced changes in root epidermal cell fate are regulated independently from physiological responses to low iron availability.

Schikora A, Schmidt W

Carl von Ossietzky Universität Oldenburg, Fachbereich Biologie, Geo und Umweltwissenschaften, D-26111 Oldenburg, Postfach 2503, Germany.

Iron-overaccumulating mutants were investigated with respect to changes in epidermal cell patterning and root reductase activity in response to iron starvation. In all mutants under investigation, ferric chelate reductase activity was up-regulated both in the presence and absence of iron in the growth medium. The induction of transfer cells in the rhizodermis appeared to be iron regulated in the pea (Pisum sativum L. cv Dippes Gelbe Viktoria and cv Sparkle) mutants bronze and degenerated leaflets, but not in roots of the tomato (Lycopersicon esculentum Mill. cv Bonner Beste) mutant chloronerva, suggesting that in chloronerva iron cannot be recognized by putative sensor proteins. Experiments with split-root plants supports the hypothesis that Fe(III) chelate reductase is regulated by a shoot-borne signal molecule, communicating the iron status of the shoot to the roots. In contrast, the formation of transfer cells was dependent on the local concentration of iron, implying that this shoot signal does not affect their formation. Different repression curves of the two responses imply that the induction of transfer cells occurs after the enhancement of electron transfer across the plasma membrane rather than being causally linked. Similar to transfer cells, the formation of extra root hairs in the Arabidopsis mutant man1 was regulated by the iron concentration of the growth medium and was unaffected by interorgan signaling.

PMID: 11299349

... 植物的部分根系处于缺Fe条件下时, 可诱导另一部分供Fe根系的Fe(III)还原酶活性和/或质子分泌增强^[28,29,30] ...

2012

5.364

0.0

J. Exp. Bot.. 2012, 63(2):859-70 DOI:10.1093/jxb/err314

Induction of root Fe(lll) reductase activity and proton extrusion by iron deficiency is mediated by auxin-based systemic signalling in Malus xiaojinensis.

Wu T, Zhang HT, Wang Y, Jia WS, Xu XF, Zhang XZ, Han ZH

Institute for Horticultural Plants, China Agricultural University, Beijing 100193, PR China.

Iron is a critical cofactor for a number of metalloenzymes involved in respiration and photosynthesis, but plants often suffer from iron deficiency due to limited supplies of soluble iron in the soil. Iron deficiency induces a series of adaptive responses in various plant species, but the mechanisms by which they are triggered remain largely unknown. Using pH imaging and hormone localization techniques, it has been demonstrated here that root Fe(III) reductase activity and proton extrusion upon iron deficiency are up-regulated by systemic auxin signalling in a Fe-efficient woody plant, Malus xiaojinensis. Split-root experiments demonstrated that Fe-deprivation in a portion of the root system induced a dramatic increase in Fe(III) reductase activity and proton extrusion in the Fe-supplied portion, suggesting that the iron deficiency responses were mediated by a systemic signalling. Reciprocal grafting experiments of M. xiaojinensis with Malus baccata, a plant with no capability to produce the corresponding responses, indicate that the initiation of the systemic signalling is likely to be determined by roots rather than shoots. Iron deficiency induced a substantial increase in the IAA content in the shoot apex and supplying exogenous IAA analogues (NAA) to the shoot apex could mimic the iron deficiency to trigger the corresponding responses. Conversely, preventing IAA transport from shoot to roots blocked the iron deficiency responses. These results strongly indicate that the iron deficiency-induced physiological responses are mediated by systemic auxin signalling.

PMID: 22058407

... 植物的部分根系处于缺Fe条件下时, 可诱导另一部分供Fe根系的Fe(III)还原酶活性和/或质子分泌增强^[28,29,30] ...

2011

9.737

0.0

Proc. Natl. Acad. Sci. U.S.A.. 2011, 108(45):18524-9 DOI:10.1073/pnas.1108684108

Nitrogen economics of root foraging: transitive closure of the nitrate-cytokinin relay and distinct systemic signaling for N supply vs. demand.

Ruffel S, Krouk G, Ristova D, Shasha D, Birnbaum KD, Coruzzi GM

Center for Genomics and Systems Biology, New York University, New York, NY 10003, USA. sandrine.ruffel@supagro.inra.fr

As sessile organisms, root plasticity enables plants to forage for and acquire nutrients in a fluctuating underground environment. Here, we use genetic and genomic approaches in a "split-root" framework--in which physically isolated root systems of the same plant are challenged with different nitrogen (N) environments--to investigate how systemic signaling affects genome-wide reprogramming and root development. The integration of transcriptome and root phenotypes enables us to identify distinct mechanisms underlying "N economy" (i.e., N supply and demand) of plants as a system. Under nitrate-limited conditions, plant roots adopt an "active-foraging strategy", characterized by lateral root outgrowth and a shared pattern of transcriptome reprogramming, in response to either local or distal nitrate deprivation. By contrast, in nitrate-replete conditions, plant roots adopt a "dormant strategy", characterized by a repression of lateral root outgrowth and a shared pattern of transcriptome reprogramming, in response to either local or distal nitrate supply. Sentinel genes responding to systemic N signaling identified by genome-wide comparisons of heterogeneous vs. homogeneous split-root N treatments were used to probe systemic N responses in Arabidopsis mutants impaired in nitrate reduction and hormone synthesis and also in decapitated plants. This combined analysis identified genetically distinct systemic signaling underlying plant N economy: (i) N supply, corresponding to a long-distance systemic signaling triggered by nitrate sensing; and (ii) N demand, experimental support for the transitive closure of a previously inferred nitrate-cytokinin shoot-root relay system that reports the nitrate demand of the whole plant, promoting a compensatory root growth in nitrate-rich patches of heterogeneous soil.

PMID: 22025711

... 最近, Ruffel等^[31]的拟南芥分根试验显示, 植物至少存在两种遗传上独立的系统信号, 分别报告植株的N供应和N需求状况 ...

1975

6.535

0.0

Plant Physiol.. 1975, 56(3):377-80

The regulation of potassium absorption in barley roots.

Glass A

Department of Botany and Zoology, Massey University, Palmerston North, New Zealand.

The dynamics of changes in K(+) influx across the plasmalemma and of internal K(+) concentrations [K(+)](1) of intact barley (Hordeum vulgare) roots were examined as the roots were converted from ;high-salt' to ;low-salt' roots. Following the transfer of plants grown in 0.5 mm CaSO(4) solutions plus various concentrations of KCl to 0.5 mm CaSO(4) solutions, influx rates increased and internal K(+) concentrations declined as a function of time and the initial K(+) status of the tissue. The relationship between plasmalemma influx and [K(+)](1) was examined over a wide range of [K(+)](1) values by growing intact plants in various concentrations of KCl. Plasmalemma influx was inversely correlated with the square of [K(+)](1). A model for the regulation of plasmalemma influx by [K(+)](1) is considered.

PMID: 16659307

1976

6.535

0.0

Plant Physiol.. 1976, 58(1):33-7

Regulation of potassium absorption in barley roots: an allosteric model.

Glass AD

Department of Botany and Zoology, Massey University, Palmerston North, New Zealand.

Plasmalemma influx isotherms for K(+) were measured in the system I concentration range (0.01-0.32 mm), for barley (Hordeum vulgare L.) roots of varying internal K(+) concentration, and Km values for influx calculated. In plants grown for several days in CaSO(4) or in CaSO(4) plus KCl solutions, as well as in plants grown in CaSO(4) for several days and then rapidly loaded with KCl during a pretreatment period, Michaelis constant values were positively correlated with internal K(+) concentrations. Influx of K(+) is shown to be sigmoidally related to internal K(+) concentration and Hill plots of influx data give linear transformations with n = 4. This information is taken as support for an allosteric model for the regulation of K(+) influx in which the "carrier" is envisaged as possessing a single external binding site for K(+) as well as four internal sites for allosteric control of influx.

PMID: 16659615

1980

0.0

1980

6.535

0.0

1975

6.645

0.0

... 与局部供N和供Pi不同, 根系在局部供K⁺条件下不发生明显的补偿生长^[36,37,38] ...

1958

36.28

0.0

... 与局部供N和供Pi不同, 根系在局部供K⁺条件下不发生明显的补偿生长^[36,37,38] ...

1990

2.474

0.0

... 与局部供N和供Pi不同, 根系在局部供K⁺条件下不发生明显的补偿生长^[36,37,38] ...

1982

0.0

... De Jager^[39]和Ma等^[40]的结果则相反, 他们发现局部供K⁺对根系生长的刺激效应分别与局部供NO₃^-和Pi相当, 但前提是缺K⁺部分完全不供K⁺或长时间分根处理后地上部的[K⁺]明显降至最适状态以下 ...

2007

2.733

0.0

Plant Soil. 2007, 291(1-2):301 - 309 DOI:10.1007/s11104-007-9197-5

Heterogeneous distribution of phosphorus and potassium in soil influences wheat growth and nutrient uptake

Qifu Ma(1) Zed Rengel(1) Bill Bowden(2)

1.Soil Science and Plant Nutrition, School of Earth and Geographical Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
2.Department of Agriculture, Western Australia, Northam Regional Office, Northam, WA 6401, Australia

Heterogeneous distribution of mineral nutrients in soil profiles is a norm in agricultural lands, but its influence on nutrient uptake and crop growth is poorly documented. In this study, we examined the effects of varying phosphorus (P) and potassium (K) distribution on plant growth and nutrient uptake by wheat (Triticum aestivum L.) grown in a layered or split soil culture in glasshouse conditions. In the layered pot system the upper soil was supplied with P and either kept watered or allowed to dry or left P-deficient but watered, whereas the lower soil was watered and fertilised with K. Greater reductions in shoot growth, root length and dry weight in the upper soil layer occurred in −P/wet than in +P/dry upper soil treatment. Shoot P concentration and total P content were reduced by P deficiency but not by upper soil drying. Genotypic responses showed that K-efficient cv. Nyabing grew better and took up more P and K than K-inefficient cv. Gutha in well-watered condition, but the differences decreased when the upper soil layer was dry. In the split-root system, shoot dry weight and shoot P and K contents were similar when P and K were applied together in one compartment or separated into two compartments. In comparison, root growth was stimulated and plants took up more P and K in the treatment with the two nutrients supplied together compared with the treatment in which the two nutrients were separated. Roots proliferated in the compartment applied with either P or K at the expense of root growth in the adjoining compartment with neither P nor K. Heterogeneous nutrient distribution has a direct decreasing effect on root growth in deficient patches, and nutrient redistribution within the plant is unlikely to meet the demand of roots grown in such patches.