Effect of silicon amendment on soil-cadmium availability and uptake in rice grown in different moisture regimes

Greenhouse experiments were conducted to study the effects of silicon on soil-cadmium availability and uptake in rice grown in an acid soil maintained under two different moisture regimes (field capacity or submergence). The silicon treatment decreased the cadmium concentration and uptake in grain and straw, while it increased the cadmium uptake in roots of plants grown on cadmium contaminated soil. Cadmium availability in soil decreased with increase in silicon applied in soil due to the rise in soil pH. The results suggest that the reduction of soil-cadmium availability could be due to cadmium immobilization caused by calcium silicate-induced pH rise in the soils. The decrease in cadmium concentration and uptake in grain and straw could be attributed to the silicon-mediated distribution of cadmium that resulted in the increased accumulation of toxic cadmium in the roots more than the edible parts of the rice plants.     

An examination of Fe deficiency stress response in relation to Fe uptake in two sorghum hybrids and their parent cultivars

Two sorghum (Sorghum bicolor L. Moench) hybrids CSH‐10 and ‐ 11 and their parent cultivars 296‐A, SB‐1055 and MR‐715 were examined for their tolerance to Fe‐deficiency stress, and also Fe uptake. It was observed that there was greater reduction of pH of the nutrient media and more rapid recovery from chlorosis only in the female parent 296‐A, and to some degree in the hybrids, but not in the male parents. The results indicated that Fe uptake‐translocation were inversely related to their Fe stress tolerance.     

不同养分配比对高粱根系生长及养分吸收的影响

为探明高粱养分吸收和根系生长对氮、磷、钾胁迫的响应,通过长期定位试验,在高粱/玉米轮作条件下研究了不同养分配比NPK、PK、NK、NP、CK对高粱根系生长及养分吸收的影响。结果表明:与NPK相比,长期不施氮肥(PK)条件下高粱总根长增加18.29%,总根体积降低26.52%,且根系主要分布在0~10 cm土层,直径小于0.5 mm细根所占比例显著增加。不施磷肥(NK)显著抑制了高粱根系生长,总根长、总根表面积和总根体积分别降低24.03%、27.48%和41.29%。不施钾肥(NP)对细根生长有明显抑制作用。不施氮、磷、钾均降低高粱对相应养分的吸收和累积,不施氮促进了营养器官中氮和钾素向籽粒转运,不施磷或钾肥抑制了氮、磷及钾的转运。高粱对养分的吸收、积累和转运与根系形态有关,不同养分积累与运转与根系形态关系表现不尽相同:氮素、钾素积累和转运与根系形态具有较好的相关性,氮素的积累和转运与植株生物量和产量的相关性大于磷素和钾素。综上,高粱根系形态及养分吸收对氮、磷及钾胁迫响应不同,该研究可为不同养分瘠薄地高粱高效栽培提供理论依据。     

Evaluation of different zinc sources for lowland rice production

 ZnSO₄, Zn-enriched farmyard manure (Zn-FYM), Zn-tetraammonia complex sorbed on FYM [Zn(NH₃)₄-FYM] and Zn-ethylenediaminetetraacetate (Zn-EDTA) were compared as Zn sources for rice production under lowland conditions. The amount of Zn supplied by Zn-EDTA was one-tenth of that supplied by the other Zn sources. Zn application to a Zn-deficient soil corrected the visual symptoms of Zn deficiency and significantly increased the total biomass, grain yields and the harvest index of rice, as well as the Zn concentration in the grain and the uptake of Zn by the straw and the grains. Even with lower rates of application (0.25 and 0.5 mg Zn kg^–1 soil), Zn-EDTA treatments gave comparable values for these parameters, and the highest "Zn-mobilization efficiency" compared to the other Zn sources. The content of diethylenetriaminepentaacetate (DTPA)-extractable Zn in the soil of the different treatments after the harvest of rice was in the order; ZnSO₄=Zn-FYM>Zn(NH₃)₄-FYM=Zn-EDTA. The application of Zn also significantly increased the number of panicles that emerged between 80 to 93 days after transplanting, though the total number of panicles at harvest remained unaffected. The calculated panicle-emergence index had a positive correlation with the grain yield of rice. The Z_n-EDTA treatment, inspite of supplying the lowest amount of Zn, as well as leading to the lowest rate of Zn uptake, produced the highest yields. Therefore, we concluded Zn-EDTA to be the most efficient source of Zn for lowland rice production. Received: 20 October 1998     

Evidence for the existence of different uptake mechanisms in soybean and sorghum for iron and manganese

A greenhouse experiment was conducted in which four varieties of soybean (Glycine max L.) and three varieties of sorghum (Sorghum bicolor L. Moench) were grown in a calcareous soil with and without soil applied FeEDDHA (0 and 2 mg Fe/kg soil). Soil applications of FeEDDHA increased Fe concentrations and reduced Mn concentrations in all varieties of soybean and eliminated Mn toxicity symptoms in Corsoy soybeans. Soil applications of FeEDDHA did not increase Fe uptake or affect Mn uptake into sorghum leaves. This study tends to support the hypothesis that there are distinct plant mechanisms between dicots and graminaceous species for the uptake of Fe, and that these mechanisms have a direct effect on Mn availability for plant uptake.     

Variations in nitrogen uptake and nitrate-nitrogen concentration among sorghum groups

Nitrogen uptake and nitrate-N concentration in forage sorghums, which are related to ground water pollution or feed quality under conditions of crop fertilization by only animal wastes, were examined. Seventy-four genotypes of sorghum and Sudan grass were tested. They were classified into 4 groups; grain type and dual purpose type sorghums (6 and 13 genotypes, respectively, Sorghum bicolor Moench), sorgo type sorghum (21, S. bicolor), Sudan type sorghum (22, S. bicolor × S. sudanense (Piper) Stapf), Sudan grass (12, S. sudanense). There was a strong correlation between dry matter (DM) yield and N uptake, with the sorgo type producing the highest DM matter yield and showing the highest N uptake. Nitrate-N, which causes nitrate poisoning of ruminants, was detected mostly in the stem of all the genotypes. The nitrate-N concentration based on DM could be calculated accurately by multiplying the nitrate-N concentration of stem on a fresh matter basis by the DM partitioning ratio of stem divided by the DM concentration of stem. The grain type and the dual purpose type of sorghums with dry stem showed the lowest nitrate-N concentration because these plants had a lower DM partitioning ratio of stem and higher DM concentration of stem. Sudan grass and Sudan type sorghum with the genetic background of Sudan grass showed higher nitrate-N concentrations owing to their ability to accumulate nitrate-N.     

Differences in iron stress response and iron uptake in some sorghum varieties

Six sorghum (Sorghum vulqaris Pers.,) varieties representing male and female lines and hybrids were examined for their response to Fe‐stress, and their ability to absorb and transport Fe in the absence and presence of phosphate or CaCO,. It was found that the variety 2077‐A (male sterile female line) and the variety CSH‐5 (hybrid of 2077‐A r CS‐3541) showed distinct mechanism to tolerate and recover completely from chlorosis induced by Fe‐stress in 10 days. Furthermore, these 2 varieties were able to reduce the pH from 6.4 to 3.8 in about 9 days, and this was increased to about 6.2 in another 6 days, which period corresponded with the onset of chlorosis and subsequent recovery. The variety 2219‐A (male‐sterile female line) was also able to withstand Fe‐stress, although the chlorosis appeared only mild throughout. This variety also reduced pH from 6.4 to 4.5, but only after 14 days in the presence of CaCO₃ (8 mg/1), and this time corresponded to the period of complete recovery from chlorosis.

There appears to be no correlation between Fe uptake capacity and tolerance to Fe‐stress in these varieties. The presence of phosphate or CaCO₃ in the absorption medium was found to increase Fe absorption and transport in a few varieties.     

锌对不同基因型玉米缺锌后的恢复效果及胚乳在缺锌中的作用

用溶液培养法研究不同Zn浓度对玉米缺Zn后恢复效果及胚乳在缺Zn中作用结果表明,不同基因型玉米缺Zn后恢复所需的适宜Zn浓度不同,敏感品种比非敏感品种要求更高的Zn浓度。缺Zn后恢复所需适宜Zn浓度高于正常培养所需适宜Zn浓度,低浓度Zn(0.1μmol/L)无恢复作用(生物量)。带上胚乳使敏感品种在缺Zn、低Zn下受抑程度(缺Zn与供Zn生物量差值)提高,而非敏感品种受抑程度反而减小。缺Zn与低Zn培养时体内P含量提高,胚乳可缓解这种影响。缺Zn后再供Zn可使体内Zn含量提高,而P含量降低,玉米对Zn产生奢侈吸收,使体内Zn含量超过正常供Zn水平,表明缺Zn后植物对Zn的要求提高。0.1μmol/L Zn恢复对“吉单120”玉米Zn含量无明显影响,但“辽单22”玉米Zn含量显著提高,这表明非敏感品种比敏感品种利用低Zn的能力更强。     

铜对伴矿景天生长及锌镉吸收性的影响

利用植物生长室水培试验和温室土培盆栽试验相结合,研究了Cu对Zn、Cd超积累植物伴矿景天生长及Zn、Cd吸收性的影响。水培试验结果显示,0.31～50μmol/L Cu处理14天对伴矿景天生长及对Zn、Cd吸收性没有显著影响;但100μmol/L Cu处理显著抑制植物生长,降低地上部Zn、Cd及根中Cd浓度,对根中Zn浓度变化没有显著影响。盆栽试验结果发现,在土壤Cu仅为3.61 mg/kg时伴矿景天生长不良,外加Cu显著促进其生长并随Cu浓度升高效应增加;但施用3 mmol/kgEDDS和再次外加250 mg/kg Cu处理使伴矿景天因体内Cu积累量过高而导致明显毒害,地上部Cu最高达1 068 mg/kg。可见低量Cu处理可促进伴矿景天生长,利于植物对土壤Zn、Cd的吸取修复,但土壤中Cu浓度过高将抑制Zn、Cd超积累植物的生长,降低其Zn、Cd吸收能力,在利用该Zn、Cd超积累植物修复高Cu的Zn和Cd污染土壤时应采取适当措施降低Cu毒害效应。     

植物对锌吸收运输及积累的生理与分子机制

锌是植物必需的营养元素,也是重金属污染元素之一。现代分子生物学的发展,极大地推动了植物体内与锌吸收运输有关转运蛋白的研究。目前发现,锌铁控制运转相关蛋白(ZIP)、自然抵抗相关巨噬细胞蛋白NRAMP、重金属ATPase酶、阳离子扩散协助蛋白CDF、Mg2+/H+的反向交换转运蛋白MHX等运输蛋白参与细胞内Zn2+离子的跨膜运输,调节植物细胞内Zn2+平衡与分配。利用数量遗传学手段在在水稻上已找到与缺锌植株死亡率和叶片青铜病发生率有关QTL位点。而在Thlaspi caerulescens 和Arabidopsis halleri植物上鉴定出控制锌含量的QTLs,为寻找控制植物高效积累Zn的遗传基础规律打下了基础。     

不同覆盖方式下减氮对玉米生长与氮素吸收、运转和分配的影响

以玉米正红505为试验材料,采用两因素随机区组设计,设置3个氮肥水平(常规施氮、减氮20％和减氮40％)和3种覆盖方式(地膜覆盖、秸秆覆盖和无覆盖),以不施氮肥无覆盖为CK,研究不同覆盖方式和氮肥水平对土壤水分与全氮含量、玉米干物质积累、氮素吸收、运转和分配及产量的影响.结果表明:(1)与CK和减氮40％处理相比,耕层...     

土壤渐进干旱过程中玉米、高粱茎水分传输能力与光合作用的协调性研究

以两种不同抗旱性的玉米品种("陕单21"和"郑单958")和高粱品种("晋中405"和"晋杂12")为对象, 研究了土壤渐进干旱过程中茎木质部水分传输能力与光合作用之间的协调关系, 试图揭示玉米和高粱品种抗旱性差异的水力生理机制。结果表明: (1)相同土壤干旱程度下, 玉米品种"郑单958"的叶水势、净光合速率(Pn)、最大光化学量子效率(Fv/Fm)和PSⅡ实际量子效率(ΦPSⅡ)高于"陕单21", 其气孔导度(Gs)及蒸腾速率(Tr)则低于"陕单21"。高粱品种"晋杂12"的Pn和ΦPSⅡ高于"晋中405"。表明玉米品种"郑单958"和高粱品种"晋杂12"的抗旱性相对较强。(2)土壤渐进干旱过程中, 玉米和高粱光合气体交换参数(Pn、Gs及Tr)的下降早于叶绿素荧光参数(Fv/Fm、ΦPSⅡ)的下降, 表明气孔关闭比PSⅡ活性受损要早。(3)抗旱性强的玉米品种"郑单958"和高粱品种"晋杂12"同时具有相对高的水分传输能力, 其抵抗气穴化形成的能力更强, 但高粱抵抗气穴化的能力不如玉米, 高粱通过快速的栓塞来减少水分散失。(4)玉米Pn和Gs对茎木质部水分传输能力下降的敏感性高于高粱, 抗旱性强的玉米和高粱品种Gs对木质部水分传输能力下降的敏感性更强。高粱能在低水分传输能力的情况下, 维持较高的光合作用, 反映了高粱保守性的水分利用策略。     

Phosphorus uptake and use efficiency in different varieties of bread wheat (Triticum Aestivum L)

Thirty spring wheat varieties were evaluated and classified into eight different groups on the basis of their grain yield performance and phosphorus (P) uptake using Metroglyph analysis. Significant variability was observed for grain and biomass yield, plant height, P content in grain and straw, total P uptake and phosphorus harvest index and P use efficiency traits. Varieties WH 711 and PBW 343 exhibited high grain yield as well as high P uptake (HGY-HP). WH 283 and UP 2425 with high index score of 19 and 16 respectively, constituted the high grain yield-medium P uptake (HGYMP) group. Both these varieties, though had similar grain yield of 5348 kg/ha, but WH 283 (12.64 kg/ha) utilized much lower P as compared to UP 2425 (16.94 kg/ha). Moreover, WH 283 (81.64) also showed higher values for phosphorus harvest index (PHI) than UP 2425 (67.88%). P uptake of WH 283 was comparable with that of Raj 3765 (10.78 kg/ha) and grouped into high grain yield and low P uptake (HGY-LP) group. The grain yield performance of these two varieties with a relatively low P uptake is reflected in their high index score for P use efficiency thus, earmarking them for low P regimes. Variety HW 2006, despite low grain yields of 4665 kg/ha had high index score of 16 due to its higher value for Phosphorus Biological (PBER) and Economic Yield (PEER) Efficiency Ratio as it has effected least (7.18 kg/ha) P mobilization. In addition high P translocation in the grain was also observed for this variety. Inter-mating of genotypes like HW 2006, UP 2338 and HW 2016 with those belonging to HGY-HP (PBW 343 and WH 711) and HGY-LP (Raj 3765 and WH 283) would be an ideal strategy to develop the cultivars for efficient phosphorus use.     

旱地高产小麦品种籽粒锌含量差异与氮磷钾吸收利用的关系

【目的】明确旱地条件下高产小麦品种籽粒锌含量差异与氮磷钾吸收利用的关系,为品种选育和科学施肥提供依据。【方法】于2013—2016年连续三年在黄土高原旱地进行田间试验,试验采用裂区设计,主处理为不施肥(CK)和施肥(NP),副处理为来自我国主要麦区的123个品种。施肥处理为N 150 kg/hm^2 (尿素,含N46%)、P_2O_5 100 kg/hm^2 (过磷酸钙,含P_2O_5 16%)。成熟期在每个品种中间2行随机抽取30穗小麦,连根拔起后,从根茎结合处剪断弃去根系,分为茎、叶、颖壳(含穗轴)和籽粒,称风干重。分析了样品中氮、磷、钾、锌含量,计算了养分的吸收量及转移量。【结果】施肥条件下高产小麦品种籽粒锌含量存在显著差异,高锌品种比低锌品种显著高54%。高锌品种的籽粒氮、磷含量分别比低锌品种显著高9%、7%,钾含量无显著差异,施肥使两组品种的氮含量显著提高,磷钾含量降低。高产高锌品种具有更高的籽粒和地上部氮、磷吸收能力,钾吸收能力与低锌品种相比无显著差异,施肥可使高锌品种的氮磷钾吸收量增幅高于低锌品种;两组品种间的氮、磷转移能力无显著差异,而高锌品种的钾转移能力较低,且两组品种的氮磷钾转移能力因施肥降低幅度一致。【结论】旱地条件下土壤养分供应充足时,高产高锌小麦品种的氮磷吸收能力强,钾转移能力弱,籽粒氮磷含量高,与低锌品种相比钾含量无显著差异。通过品种选育可同时提高旱地高产小麦籽粒锌和蛋白质含量,并提高磷含量。考虑到磷含量高时会降低籽粒锌的生物有效性,生产中通过施肥措施,适当调控磷肥,增加氮肥,在提高小麦籽粒氮锌含量的同时提高籽粒锌的生物有效性。     

The role of root plasma membrane ATPase and rhizosphere acidification in zinc uptake by two different Zn-deficiency-tolerant wheat cultivars in response to zinc and histidine availability

ABSTRACT

We investigated the effect of histidine (His) and Zn deficiency on H⁺-ATPase activity and H⁺ release from wheat roots. Two bread wheat (Triticum aestivum L. cvs. Kavir and Back Cross Roshan) were grown in a nutrient solution for four weeks before being transferred to treatment solutions consisting of two concentrations of His (0 and 50 µM) and two concentrations of Zn (0 and 10 μM). The Zn-only and the Zn+His treatments were observed to release more H⁺ in the root media than did the control ones, with the highest achieved under the Zn+His treatment which was roughly 2.1 times higher than that under the control conditions. The H⁺ release from wheat roots increased slightly but significantly in the presence of only His when compared with the control solutions. The hydrolytic and transport activities of H⁺-ATPase were affected by both Zn deficiency and His supply. In both cultivars, application of Zn and His resulted in a higher hydrolytic activity of H⁺-ATPase when compared with the control solutions. The highest hydrolytic activity of H⁺-ATPase in the root plasma membrane vesicles was achieved with the Zn+His treatment. The ‘Back Cross Roshan’ exhibited a higher (PM) H⁺-ATPase activity and H⁺ pumping than did ‘Kavir’.     

粮食作物锌的吸收运转分配和改善子粒锌含量的理论与技术途径

基于前人取得的主要成果，系统分析了从土壤锌有效性到锌在子粒部位的积累主要过程及其控制点，从三方面：1）植株对锌的吸收过程；2）锌在地上部各营养器官间的运转分配过程；3）锌从营养器官向子粒部位的运转过程，总结并提出今后应利用作物锌高效性的种质资源特点，通过传统育种与生物技术方法选育出锌高效积累型品种和合理配套的栽培技术等农艺措施，提高作物子粒锌的含量。     

不同株高类型杂交高粱产量、养分吸收及品质对氮肥的响应

  【目的】  生产中我国杂交高粱品种株型差异较大。研究不同株高类型高粱产量、品质和养分利用效率对氮肥的响应,为高粱优质高效生产提供理论依据。  【方法】  采用田间试验方法,供试作物为我国不同生态区具有代表性的不同年代育成的40个杂交高粱品种。根据株高将40个杂交高粱品种分为矮秆 (<1.3 m)、中秆 (1.3～1.6 m) 和高秆 (>1.6 m),每个品种均设置不施氮 (N0) 和施N 150 kg/hm2 (N150) 两个处理。高粱成熟期调查地上部生物量、产量及产量构成,分析高粱地上部氮磷钾养分吸收量、氮吸收与利用效率,测定籽粒淀粉、蛋白质及单宁含量。  【结果】  随株高增加,高粱地上部干物质累积量和籽粒产量明显增加,但对收获指数没有显著影响。施氮显著提高了中秆和高秆高粱品种的产量和穗粒数,但降低了千粒重,而施氮对矮秆品种的产量及其构成没有显著影响。同一氮处理条件下,高秆和中秆品种的籽粒产量、穗粒数及地上部氮累积量没有显著差异。高秆品种的磷、钾累积量最高,矮秆最低,施氮提高了3个株高品种的磷钾累积量,特别是矮秆品种的磷钾累积量。3个株高品种的氮吸收效率相当,为25.5%～30.4%,但高秆和中秆品种籽粒氮利用效率显著高于矮秆品种。株高与高粱籽粒淀粉含量呈正相关,与蛋白质含量呈负相关,与单宁含量无显著相关性。相同氮处理下,高秆和中秆品种籽粒淀粉、蛋白质和单宁含量相当。施氮降低了所有品种籽粒淀粉含量,提高了蛋白质含量,且对矮秆品种的影响大于中秆和高秆品种。  【结论】  不同株高类型杂交高粱品种的收获指数和氮吸收效率没有明显差别,高秆和中秆高粱品种具有较高的穗粒数、籽粒产量、淀粉含量及氮利用效率,中秆品种的氮磷钾养分需求量低于高秆品种。施氮降低了籽粒淀粉含量,提高了中秆和高秆品种的穗粒数进而提高产量,但矮秆高粱产量及其构成对氮不敏感。综合考虑产量、肥料利用效率和满足高粱机械化收获对株高的要求,建议生产中优先考虑株高为1.3～1.6 m的杂交高粱品种。     

不同铵硝配比下不同硅效应水稻的硅吸收动力学特征

将水稻移植到0.2 mmol/L Ca SO4溶液中饥饿2 d,采用改进耗竭法研究了3种铵硝配比条件下3个不同硅效应水稻(耐低硅的硅高效水稻特优998和不耐低硅的硅高效水稻特优248以及硅不敏感水稻博Ⅱ优15)硅吸收动力学特征。结果表明:作图法和双倒数法动力学方程准确性高,达到极显著水平;不同铵硝配比条件水稻硅吸收动力学曲线均符合Michaelis-Menten酶动力学模型的描述;铵硝配比对不同的硅效应水稻的硅载体数量影响不显著,显著影响水稻对硅的亲和力。本实验条件下铵硝配比50/50有利于水稻特优248对硅的吸收,铵硝比75/25时吸收速率最低;特优998对硅有较高的亲和力,可能是其耐低硅高效的遗传性差别。     

不同年代玉米品种干物质积累与钾素吸收及其分配

为比较我国玉米生产中不同年代大面积推广的不同品种生长发育和干物质积累规律,及其对钾素的吸收和分配的变化特点,选择了上世纪50年代至今的6个玉米品种（白马牙、金皇后、中单2号、唐抗5号、农大108和郑单958）为材料,在田间相同条件下进行研究。结果表明,与早期品种相比,现代玉米品种的发育进程慢,生育期长,叶面积大,叶片衰老慢。在大喇叭口期,不同年代玉米品种的干重无显著差异; 但其后现代品种的生长速率显著增加,干重积累速率也显著高于早期品种,其干物质积累高峰出现在吐丝期后,吐丝期后植株的干物重增加量约等于子粒产量,表明子粒产量与吐丝期后的干物质积累相关。与干物质累积规律不同,不同年代玉米品种的含钾量在大喇叭口期就有明显差别,表现为50年代品种70年代品种现代品种。玉米对钾的吸收主要在吐丝期之前完成,吐丝期后钾素累积速率明显下降, 50年代品种的钾素净增量甚至为负值。子粒中的钾主要来自于营养器官的再转移,从叶片中的转移量尤其多。与早期品种相比,绿熟型现代品种农大108和郑单958从叶片中转出的钾更多。综上,不同年代玉米品种的不同点在于,现代品种的叶面积更大,吐丝期后生育期更长,叶片衰老更慢,有利于子粒灌浆,形成高产; 相同点在于,干物质和钾素的累积高峰不同步,子粒产量主要来自于花后的干物质积累,而子粒中的钾主要来自于营养器官的再转移。     

Shoot and root biomass,phosphorus and nitrogen uptake of spring wheat grown in low phosphorus and moisture content conditions in a pot experiment

Abstract

A pot experiment was done in a greenhouse to investigate the effect of low phosphorus (P) and moisture content on growth and yield components of four spring wheat (Triticum aestivum L.) varieties. Days to emergence of seedlings were shortened, plant height, tiller number, and SPAD (Soil-Plant Analyses Development) index of the leaves were significantly (p?R²) values ranging from 0.72 to 0.90. The study underlines the strong relationship between moisture, P availability and uptake and provides more information on P nutrition during the vegetative stage of wheat in moisture and P deficient soils.