燕麦对盐碱胁迫的生理响应

通过分析渗透调节物质脯氨酸和可溶性糖含量的变化,利用洗叶技术分析燕麦叶片洗脱物的离子组成,以及对气孔周围结晶的X—ray分析,并利用扫描电子显微镜观察燕麦叶片的表面结构,研究了燕麦对盐碱胁迫的生理响应。结果表明,在盐碱胁迫下,燕麦叶片中脯氨酸和可溶性糖含量增加;经过混合盐处理后,叶片洗脱物主要由Clˉ、Na^＋、K^＋、HCO3ˉ、Mg^2＋和Ca^2＋等离子组成,不含CO3^2-和SO4^2-,其中Clˉ、Na^＋、K^＋含量极显著高于对照,HCO3ˉ、Mg^2＋含量显著高于对照,Ca^2＋含量与对照差异不显著;通过扫描电镜观察叶片表面,发现气孔周围分布着盐结晶,表明燕麦通过气孔排盐适应盐碱胁迫。     

Grapevine Growth and Physiological Responses to Iron Deficiency

ABSTRACT

Iron (Fe) deficiency is one of the major abiotic stresses affecting fruit tree crops growing in calcareous soils in the Mediterranean region. A better understanding of changes in the growth and physiological characteristics of grapevine plants during the development of Fe deficiency will help to improve Fe fertilizer management recommendations. An experiment was conducted in field conditions to determine the effects of Fe deficiency during vegetative growth on leaf photosynthesis, dry matter accumulation, pigments, and other physiological parameters. Iron deficiency considerably decreased leaf net photosynthetic rate, leaf area, and dry matter accumulation. Depressed photosynthesis and plant growth resulted in increased fruit abscission and changes in dry matter among plant tissues. The results help explain the effects of Fe deficiency on suppression of grapevine growth and yield and provide information for improving the diagnosis of Fe deficiency in grapevine production.     

Cotton Growth and Physiological Responses to Boron Deficiency

Abstract

Boron (B) deficiency is common in some cotton (Gossypium hirsutum L.) growing regions of the world. A better understanding of changes in the growth and physiological characteristics of cotton plants during the development of B deficiency will help us to define field diagnosis techniques and improve B fertilizer management recommendation. An experiment was conducted in a controlled‐environment growth chamber to determine effects of B deficiency during early vegetative growth on leaf photosynthesis, plant dry matter accumulation, photosynthetic assimilate partitioning, and other physiological parameters. Boron deficiency considerably decreased leaf net photosynthetic rate, plant height, leaf area, fruiting sites, and dry matter accumulation during squaring and fruiting. Depressed photosynthesis and plant growth (especially fruits and roots) resulted in increased fruit abscission and changes in dry matter partitioning among plant tissues. The results help explain effects of B deficiency on suppression of cotton growth and yield and provide information for improving the diagnosis of B deficiency in cotton production.     

Physiological and Biochemical Responses of French Bean to Excess Cobalt

ABSTRACT

French bean (Phaseolus vulgaris L.) cv. ‘Anupama’ was grown in refined sand at variable levels of cobalt (Co), i.e., 0.0001 (control), 0.05, 0.10, 0.20, 0.40, and 0.50 mM, supplied as cobalt sulfate. The symptoms of excess Co (0.50 mM) appeared at day 35. In addition to growth depression, the young leaves developed chlorosis from the apex leading toward the base; the chlorosis intensified, changed to necrosis, and the infected leaves dried and withered. Under excess Co (> 0.0001 mM), the flowers produced were fewer in number, smaller, and many failed to mature, leading to lower seed yield. Excess Co (> 0.0001 mM) decreased the biomass, seed yield (number and weight), concentration of chlorophyll, Hill reaction activity, and activity of catalase, and deteriorated the quality of produce (sugars, starch, and protein nitrogen (N)), but it increased the concentration of phenols and activity of certain enzymes, i.e., peroxidase, ribonuclease, and acid phosphatase. The concentration of Co in various parts of French bean increased with an increase in Co supply and that of iron (Fe) decreased concomitantly. The values of threshold of toxicity and toxicity of Co were 26 and 72 μg g^?1 in young leaves of French bean, respectively.     

薄壳山核桃幼苗对干旱胁迫的生理生化响应

为探究薄壳山核桃幼苗对干旱胁迫的适应能力,本试验以一年生薄壳山核桃幼苗为材料,采用盆栽控水试验,设置正常供水(CK)、轻度干旱胁迫(LD)、中度干旱胁迫(MD)和重度干旱胁迫(SD)4种水分处理梯度,测定相关生理生化指标并分析叶片超微结构。结果表明,在干旱胁迫50 d时,随着干旱程度加剧,叶绿素a含量呈下降趋势,CK的叶绿素a含量分别是LD和MD的1.22和1.35倍;MD叶片气孔大量闭合,关闭密度达236个·mm^-2;LD和MD的净光合速率(Pn)较CK分别下降了17.16%和58.42%。此外,渗透调节物质含量在干旱胁迫下显著提高,其中LD和MD的可溶性蛋白含量较CK分别增加了141.68%和204.17%。在干旱胁迫50 d时,MD幼苗的超氧化物歧化酶(SOD)活性达到峰值,为367.93 U·mg^-1prot,而过氧化物酶(POD)活性较干旱胁迫20 d出现下降。各水分梯度处理下,LD幼苗长势最好;MD叶片叶绿体结构破坏严重,基粒片层模糊不清;SD幼苗死亡,故为满足幼苗生长需要,应保证种植地土壤含水量达到田间持水量的35%以上。本研究...     

Short-Term Physiological Responses of Mosses to Atmospheric Ammonium and Nitrate

Many bryophytes rely to a large extent on atmospheric deposition for their nutrient uptake.However, increasing levels of atmospheric ammonium NH ₄ ⁺ and nitrate NO ₃ ^- attract concern as to the possible harmful effects onbryophytes from these two nutrient sources. Changes in nitrate reductase (NR) activities, cation(Ca, K and Mg), total nitrogen (N) and organic acid concentrations were investigated for themosses, Racomitrium lanuginosum, Rytidiadelphus loreus and Philonotis fontana, in response to asingle field misting with 3 mol m^-3 NH ₄ ⁺ and NO ₃ ^- . Increases of 20% were recordedfor tissue N content, 48 hr after misting with N containing solutions. When labelled NH ₄ ⁺ or NO ₃ ^- were applied to R. Lanuginosum at 1, 3 and 6mol m^-3 concentrations, partitioning ofincorporated ¹⁵N between different tissueregions occured, with the highest N uptake in the upper stem and leaves. High concentrations ofapplied N resulted in reduced efficiency of N uptake. NH ₄ ⁺ applications caused declines in NR activities, organic acidsand cations, whereas, NO ₃ ^- treatments causedthe reverse response. Changes in cation contents, organic acids and NR activity reflect short-termregulation of N metabolism in the presence of defined N sources, as well as potential mechanismsof regulating cell pH homoeostasis. The consistency of physiological responses, especially NRactivities, over short-term pollution episodes, provides evidence for their use as indicators of both NH ₄ ⁺ and NO ₃ ^- pollution.     

两花生品种对镉胁迫的生理响应及其差异

根据本实验室前期的水培实验,利用盆栽培养,研究了外加土壤Cd处理浓度为12 mg kg-1时花生植株的生理毒害反应及其品种间差异。以两个不同的花生品种花育22和花育20为实验材料进行对比研究,分别测定三个不同时期花生叶片叶绿素含量和细胞膜透性、根系和叶片丙二醛含量、抗氧化酶体系活力及花生产量。结果表明:在外加土壤Cd处理浓度为12mg kg-1时,叶片叶绿素含量和抗氧化酶体系活力随着处理时间的增加而降低,Cd处理组相对于对照组都有所下降,且花育20下降幅度要远大于花育22,尤其在成熟期,镉处理组中花育20的SOD、POD和CAT活力显著低于对照组;而细胞膜透性和丙二醛含量则是随着处理时间的增加而增加,且Cd处理组相对于对照组都有所增加,花育20增加幅度要大于花育22。产量测定结果显示,花育22下降13.14%,花育20下降26.98%。结合各指标的变化情况分析可知,花生对Cd污染存在着较大的品种间差异;其中过氧化物岐化酶(SOD)、丙二醛(MDA)和叶绿素三个指标变化幅度较大,为初步筛选选育抗Cd花生品种的参考指标和花生Cd污染的诊断指标提供依据。     

几种水生观赏植物对城市污水的生理响应

主要研究了石菖蒲、泽泻、菖蒲、黄花鸢尾、千屈菜这5种常见水生观赏植物对城市污水的生理生化变化,分别在第5 d,10 d和15 d对植物叶片膜脂过氧化(MDA、电导率)、体内保护系统酶(CAT、POD)、非酶类(游离Pro)及根系活力等抗性生理指标进行测定,探讨植物抗污水逆境的能力。研究结果表明,不同植物适应污水环境能力不同。其中,黄花鸢尾在污水处理下的抗逆性最强,与对照相比其电导率和丙二醛含量变化不大,而一些植物在实验初期受到污水胁迫,电导率和丙二醛含量较对照有上升的现象;同时,实验初期黄花鸢尾中游离Pro含量、POD和CAT活性及根系活力的增强,菖蒲根系活力的增加,千屈菜POD、CAT酶活性的升高,泽泻根系活力、POD、CAT酶活性的升高,都是水生植物对污水环境的生理适应。黄花鸢尾抗逆性强,是一种值得推荐的净化污水的湿地植物。     

Some Physiological Responses of Black-Eyed Pea to Iron and Magnesium Nanofertilizers

Key players in photosynthesis, iron (Fe) and magnesium (Mg), in nano and common forms were considered for foliar application of black-eyed pea. Factorial experiments in three replicates were designed based on completely randomized blocks containing Fe (0, 0.25, and 0.5 g L^?1; in two forms: nano and common) and Mg (0, 0.5 g L^?1 nano, and 0.5 g L^?1 common). The elements were applied 56 and 72 days after sowing over the leaves, and data were collected after day 85. Iron had significant effect on yield, leaf Fe content, stem Mg content, plasma membrane stability, and chlorophyll content. The greatest effect was obtained by two treatment combinations of 0.5 g L^?1 common Fe + 0.5% nano-Mg and 0.5 g L^?1 common Fe + 0.5 g L^?1 common Mg. In general, almost all analyzed traits were improved by foliar application of these two elements, probably as a result of more efficient photosynthesis.     

两种稗属牧草生长生理指标对光周期变化的响应

湖南稷子（Echinochloa frumentacea）和宁夏无芒稗（Echinochloa crusgalli）是改良盐碱土壤的优质稗属牧草。本研究通过设置昼/夜8h/16h（记为Ph8）、12h/12h（Ph12）和16h/8h（Ph16）3种不同的光周期处理,测定不同处理下两种稗属牧草的株高、叶宽、穗重、丙二醛（MDA）、可溶性蛋白、叶绿素含量、光合和叶绿素荧光参数等生长生理指标,以探究两种稗属牧草生长生理特性对光周期改变的响应规律,为优质牧草异地引种及高产栽培提供科学依据。结果表明：随着光照时间的延长,（1）湖南稷子和宁夏无芒稗的叶宽、穗鲜重、穗干重均呈“倒V”型变化趋势,而株高呈上升趋势,各处理下株高、穗鲜重和穗干重均表现为湖南稷子高于宁夏无芒稗。（2）两种稗属牧草的MDA含量呈现出“V”型变化过程。（3）可溶性蛋白含量呈“倒V”型变化过程。（4）两种稗属牧草的净光合速率、叶绿素含量、最大光化学效率（PII）及其潜在活性均呈现“倒V”型变化过程,在Ph12处理下达到最大值,且在三种光周期处理下,湖南稷子的净光合速率高于宁夏无芒稗。本研究表明,光照时长中等条件（12h）能够显著促进湖南稷子和宁夏无芒稗的叶绿素和可溶性蛋白合成,增强光合作用,提高产量,且对湖南稷子产量的促进作用高于宁夏无芒稗。     

镉对龙葵幼苗生长和生理指标的影响

采用营养液培养法研究了镉胁迫条件下龙葵幼苗生长、生理响应及镉积累特性。结果表明,镉胁迫下,龙葵幼苗生长受到一定程度的抑制,并且具有浓度效应和时间效应。镉胁迫还导致龙葵叶片色素含量下降。叶绿素a、b和类胡萝卜素平均含量在高浓度镉（150μmol·L^-1）处理条件下分别较对照降低55．5％、63．9％和43．3％。低浓度镉（25μmol·L^-1）处理15d内显著促进龙葵幼苗根系活力,平均根系活力较对照上升10．4％,而高浓度镉处理下,根系活力呈现先升后降的趋势,镉处理10d之后达到峰值;随着镉浓度的升高和胁迫时间的延长,龙葵幼苗叶片相对电导率、丙二醛（MDA）含量和渗透调节物质均呈现显著上升趋势。相对于对照植株,低浓度镉处理下龙葵叶片平均相对电导率、MDA含量、可溶性糖和脯氨酸含量上升17．7％、117．7％、5．6％和95．3％,而高浓度镉处理下上升幅度更大,分别为39．0％、194．6％、56．3％和758．0％。从积累部位来看,镉主要积累在龙葵幼苗地上部,镉含量由高到低依次为叶片〉茎〉根系,高浓度镉胁迫20d之后根茎叶镉含量为5d时的1．73、1．49和1．40倍,分别为1287．25、1718．14和2385．27μg·g^-1DW。     

荆芥幼苗对盐胁迫的生理响应

为探究盐胁迫对荆芥幼苗生理特性的影响,采用盆栽砂培试验,研究不同浓度盐胁迫(0、25、50、75和100 mmol·L^-1 NaCl)下荆芥幼苗生长、质膜稳定性、渗透调节、抗氧化酶系统、离子吸收和分配的变化。结果表明,随着盐浓度的增加,荆芥盐害指数逐渐升高,幼苗株高增加速率和比叶面积均逐渐降低,单株干重和叶绿素含量均呈先增加后减少的趋势,且均在25 mmol·L^-1 NaCl处理下达到最大;叶片中丙二醛(MDA)含量和电解质渗漏率均显著增加;可溶性蛋白和脯氨酸含量均呈先增加后减少趋势,且分别在50和75 mmol·L^-1 NaCl处理下达到最大,而可溶性糖含量则不断上升;超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性均呈先上升后下降的趋势,在25 mmol·L^-1 NaCl处理下达到最大,而过氧化物酶(POD)活性则持续下降。盐胁迫下,荆芥的根、茎、叶大量积累Na^+,但主要集中在地上部分,同时各部位K^+、Ca²⁺含量及K^+/Na^+、Ca²⁺/Na^+值均显著下降。综上,荆芥幼苗对盐胁迫极为敏感,但对低浓度的盐胁迫(25 mmol·L^-1 NaCl)具有一定的耐受性。本研究结果为荆芥的规范化栽培和抗逆驯化研究奠定了理论基础。     

Physiological Responses of Calcium-Efficient and Calcium-Inefficient Tomato Genotypes to Differential Bacterial Wilt Conditions

Bacterial wilt (BW) disease, caused by Ralstonia solanacearum, can severely limit tomato (Solanum lycopersicum) production in southern United States. Tomato genotypes display variable responses to BW disease. The physiological mechanism underlying BW resistance is not well understood. In this study, experiments were conducted to compare two tomato genotypes, PI117566 [calcium (CA)–efficient] and PI109315 (Ca-inefficient), for wilting, shoot growth, final fresh weight, and shoot Ca concentrations when inoculated with R. solanacearum. The inoculation concentration of R. solanacearum varied from 0 to 10⁸ colony forming units/ml. Genotype PI109315 appear to be more BW-resistant compared with genotype PI117566 under sufficient Ca conditions. Furthermore, we found that genotype PI109315 had greater shoot growth and final fresh weight than genotype PI117566. These findings implied that Ca-efficient tomato genotypes may not play a key role in BW resistance of tomato under sufficient Ca conditions because Ca efficiency showed no effect on the suppression of BW.     

燕麦幼苗对盐胁迫和碱胁迫的生理响应差异

为探讨‘定莜6号’燕麦对盐胁迫和碱胁迫的生理响应差异,采用砂培法研究了不同浓度(0mmol/L,50mmol/L,100mmol/L,150mmol/L和200mmol/L)NaCl和NaHCO3胁迫对幼苗生长、活性氧代谢和渗透调节物质积累的影响。结果表明:(1)随着NaCl和NaHCO3浓度增大,燕麦植株干重及叶片K+含量和K+/Na+明显下降,叶片Na+含量及O2·产生速率、H2O2和MDA含量显著提高。NaHCO3胁迫的上述指标变幅大于NaCl胁迫。(2)不同浓度NaCl和NaHCO3胁迫均引起燕麦叶片SOD、CAT、POD和APX活性提高或降低;NaHCO3胁迫与NaCl胁迫相比抗氧化酶激活或受抑的程度在不同Na+浓度下表现不同。NaHCO3胁迫的燕麦叶片ASA和GSH含量低于相同Na+浓度下的NaCl胁迫,100 mmol/L Na+浓度下GSH含量则相反。(3)50~150 mmol/L Na+浓度下,NaHCO3胁迫的燕麦叶片具有比NaCl胁迫更高的可溶性糖含量,200mmol/L Na+浓度下可溶性糖含量则相反。NaHCO3胁迫的燕麦叶片游离氨基酸含量明显高于NaCl胁迫,脯氨酸含量则相反。上述结果表明,燕麦的耐碱性低于耐盐性,这可能与碱胁迫引起Na+、K+更严重的失衡及活性氧清除系统变化和渗透调节物质积累存在差异有关。     

Growth and Physiological Responses of Triticum aestivum and Deschampsia caespitosa Exposed to Petroleum Coke

Methylibium petroleiphilum PM1, which is capable of degrading of methyl tert-butyl ether (MTBE), was immobilized in calcium alginate gel beads. Various applications were explored to increase the mechanical strength of these gel beads. The introduction of 0.3 mol/L calcium chloride into the crosslinking solution, 0.002 mol/L calcium chloride into the growth medium, and 0.2% polyethyleneimine (PEI) as chemical crosslinking agent increased the stability of the Ca-alginate gel beads under the operation conditions of the bioreactor. The degradation rates of MTBE by the immobilized cells in the bioreactor system operated in batch and continuous mode , respectively, were compared. A MTBE biodegradation rate of 5.79 mg/L·h was reached for over 400 h (50 batches), and the immobilized cells in the bioreactor removed >96% MTBE during 50 days of operation. Molecular analysis of the PM1 cells revealed that microbial growth occurred predominantly as microcolonies in the outer area of the beads during the first 20 days of operation. The results of this study show that a continuous-mode, fixed-bed bioreactor reactor coupled with PM1-immobilized cells is a promising technology for remediating MTBE-contaminated groundwater.     

Physiological and Growth Responses of Transplants of the Moss Pseudoscleropodium purum to Atmospheric Pollutants

Chlorine is the most commonly used chemical for water and wastewater disinfection worldwide, and it reacts with both ammonia and dissolved organic nitrogen. Using the salicylate spectrophotometric method, effects of glycine on the classic breakpoint chlorination are studied using glycine as a surrogate for dissolved organic nitrogen. The results show that the shape of the breakpoint chlorination curve with glycine was analogous to that of water without glycine. Increasing the glycine concentration moves the chlorination breakpoint curve to the right, demonstrating that more chlorine must be added to replace the chlorine consumed by glycine and yield the desired residual active chlorine concentration. At the peak of the chlorination breakpoint curve, both NH₂Cl and mono-chlorinated organic chloramine reach their maximum. The Cl₂/N ratio of the peak is linearly related to the glycine concentration, and our calculations indicate that the maximum of mono-chlorinated organic chloramine formation by glycine chlorination occurs at a stoichiometric ratio of 1:1; the same as that for chlorinating ammonia to NH₂Cl. The distribution of NH₂Cl and organic chloramines is controlled by [Gly]/[NH₃-N]. At the breakpoint, ammonia and glycine are completely oxidized by chlorine, which leads to chlorine depletion. The stoichiometric ratio for the complete oxidation of glycine was 3:1, larger than that for complete oxidation of ammonia (2:1). For the different stoichiometric ratio in reaction of oxidation of ammonia and glycine, the sum of ammonia and glycine cannot be used as a chlorine dosage control parameter. The chlorine control method involving ammonia and glycine for chlorine and chloramination process is established.     

2种雀稗属牧草对低磷胁迫的生长、生理应激响应

为比较宽叶雀稗(Paspalum wettsteinii)和巴哈雀稗(Paspalum notatum)适应低磷胁迫的能力,揭示其对低磷胁迫的形态及生理响应机理,试验以石英砂为基质,定期浇灌200μmol·L-1(常磷)、20μmol·L-1、2 μmol· L-1的Hoagland营养液模拟低磷胁迫处理,分别在磷处理...     

Physiological Responses of Leymus Chinensis to Long-Term Salt,Alkali and Mixed Salt-Alkali Stresses

The aim of this study was to evaluate the physiological responses of Leymus chinensis (Trin.) Tzvel exposed to long-term salt, salt-alkali, and alkali stress in order to elucidate how L. chinensis can survive under alkaline-sodic soils. L. chinensis (30 days after germination) were stressed with salt [SS; sodium chloride (NaCl)], mixed salt-alkali [MS; molar ratio of NaCl: sodium carbonate (Na₂CO₃) = 2:1] and alkali salt (AS; Na₂CO₃) at four different levels of sodium (Na⁺) concentration (0, 75, 150, and 300 mM) for 60 days. L. chinensis showed 100% survival rate at all treatments except 300 mM SS (33.3%) and AS (18.9%). The growth and physiological parameters of survival plants were measured. As anticipated, growth of L. chinensis was inhibited after stresses, which reflected in the decline of plant height, dry weight and tiller number following the increased Na⁺ concentration. The content of Na⁺, proline, and soluble sugar in L. chinensis increased with the increasing Na⁺ concentration, suggesting that L. chinensis need to accumulate inorganic and organic solutes for resisting osmotic stress induced by various salt stresses. These processes ensure the water balance that can provide a relative normal physiological environment for L. chinensis. Potassium (K⁺) content of L. chinensis kept at a relative lower level than control to ensure the normal physiological processes. Chlorophyll content of stressed plant increased slightly compared to control plants, which can produce more energy for L. chinensis resisting various stresses. The increased malondialdehyde (MDA) content of stressed plants showed the damage of various stresses. Among the three treatments (SS, MS, and AS), the injury extent for L. chinensis can be expressed by AS>SS>MS, and MS was the most complicated for the counterbalance effects of soil electrical conduction and pH.     

不同基因型番茄幼苗对镉胁迫的生理响应及镉吸收差异

采用盆栽试验,通过研究不同浓度镉（1、5、10mg·kg-1）胁迫下4种基因型番茄圣粉1号、东圣1号、农城906和宝冠1号幼苗地上部及根部生物量、镉吸收量、活性氧含量（ROS）及其他生理指标,筛选出镉低积累基因型番茄品种。结果表明,不同基因型番茄对镉胁迫响应存在差异。随镉处理浓度增加,4个品种番茄幼苗地上部生物量显著下降（P〈0.05）。地上部Cd吸收量呈增加趋势,在中浓度（5mg·kg-1）镉处理下达到峰值,品种间为宝冠1号〉圣粉1号、农城906〉东圣1号。4个品种番茄幼苗Cd转移率随镉处理浓度增加显著降低,其中东圣1号Cd转移率较低,根部Cd滞留较多,向地上部转移较少。4个品种番茄幼苗生理活性存在差异,宝冠1号番茄幼苗ROS含量及抗氧化酶（POD,CAT）活性随镉处理浓度增加变化幅度较大,东圣1号变化幅度相对较小。综合各项指标,4个基因型番茄中东圣1号为镉低积累品种。     

镉胁迫下小麦根系的生理生态变化

本文通过水培和砂培两种方法 ,研究了镉胁迫下小麦 (TriticumaestivmL .)根系的生理生态变化。通过研究镉对小麦根系生长发育状况 ,根系活力 ,根系对矿质元素的吸收 ,探讨镉胁迫下植物根系的生理生态效应。研究结果表明 :镉影响根系的长度、生物量、体积和根系活力。Cd2 + 在低浓度 (处理浓度低于 5mg/L)作用下 ,随处理浓度的升高 ,刺激小麦根系的长度、生物量、体积相应地升高 ;当处理浓度高于相应浓度时 ,根长度、生物量、体积相应随浓度升高而降低。镉胁迫下根系活力受到抑制。水培和砂培中 ,镉对根系的影响趋势一致 ,但是影响幅度有差异。砂培好于水培。镉影响小麦根对矿质元素的吸收 ,Ca、Cu、Fe、K、Mg、Mn、Na、Zn吸收情况不太一致。Ca、Cu、Fe、Mg、Mn、Na的吸收量随Cd2 + 浓度升高而增加 ,K、Zn的吸收量随Cd2 + 浓度升高而减少