Fe—EDDAH对矫治秦美猕猴桃叶片失绿和营养元素组成的影响

在陕西石灰性土壤秦美乌鲁木齐果园施用不同剂量叶绿灵（Fe-EDDHA）,结果表明,萌芽期株施45g叶绿灵对籍治秦美猕猴桃叶片失绿黄化效果显著,可一直维持到当前落叶。同黄化对照植株相比,叶片叶绿素含量增加182.5%,活性铁含量提高53.2%,果实品质得到明显改善,施用叶绿灵还改善了叶片营养元素的含量。     

Fe-EDDHA对矫治秦美猕猴桃叶片失绿和营养元素组成的影响

在陕西石灰性土壤秦美猕猴桃果园施用不同剂量叶绿灵 (Fe- EDDHA) ,结果表明 ,萌芽期株施 45 g叶绿灵对矫治秦美猕猴桃叶片失绿黄化效果显著 ,可一直维持到当年落叶。同黄化对照植株相比 ,叶片叶绿素含量增加 1 82 .5 % ,活性铁含量提高 5 3 .2 % ,果实品质得到明显改善。施用叶绿灵还改善了叶片营养元素的含量     

管道输液滴干对苹果缺铁失绿症的影响

为探索防止果树缺铁失绿症方案,该研究以Fe-N为铁肥品种,以管道输液滴干的方式对中秋王苹果树输入不同浓度的溶液,测定叶片的叶绿素相对含量(SPAD值)、百叶重、百叶厚、全铁和活性铁含量及荧光参数等指标。结果表明:Fe-N管道输液滴干处理显著提高了苹果叶片的SPAD值、百叶重、百叶厚、全铁以及活性铁的含量,发现叶片SPAD值与活性铁含量之间呈现良好的线性关系(相关系数为0.899),表明叶片SPAD值可以作为苹果缺铁诊断指标,同时也说明了苹果树体叶片黄化主要是由于活性铁含量低所致。16.4×10~(-3)mol·L~(-1)Fe-N溶液处理的叶片SPAD值、百叶重、百叶厚、全铁及活性铁含量显著高于其它处理,分别比对照提高了89.66%、20.42%、9.26%、158.0%、277.4%,该处理荧光参数也达到了较优水平。该研究结果为管道输液滴干防止苹果缺铁失绿症的应用奠定了基础。     

温敏失绿突变体水稻1103s在失绿过程中全叶蛋白的变化

从全叶蛋白比较入手,研究了温敏失绿突变体水稻（ＯｒｙｚａｓａｔｉｖａＬ．）１１０３ｓ失绿前、后的变化,并结合该突变体在不同温度处理和遗传背景下叶片全蛋白的变化特征分析了变温诱导与失绿的关系。结果表明,诱导后１１０３ｓ的叶片上,失绿部分的组织中没有出现冷胁迫的迹象,其Ｒｕｂｉｓｃｏ的大、小亚基表现正常。一个５１ｋＤ（ＰＩ＝４．５）的特异蛋白Ｐ１在失绿部分的组织中消失,而在叶片绿色部分的组织中检测到了Ｐ１蛋白,不过量有所减少,说明在失绿叶片上突变基因的表达存在组织差异性。Ｐ１蛋白在常温下生长的１１０３ｓ叶片中为一大量蛋白,此蛋白在“８９０２ｓ”、“窄叶青８号”等品种中均可检测到;并且持续低温处理的１１０３ｓ植株和１１０３ｓ×８９０２ｓ杂交一代的叶片中Ｐ１蛋白的表达未受影响。由此推测,Ｐ１蛋白是水稻叶片中的一个与叶绿素的代谢过程密切相关的重要功能蛋白。在１１０３ｓ中,Ｐ１蛋白的变化不是温度诱导的直接后果,而是受突变所导致的温敏过程调控的下游变化。     

锰有效性对大豆锰、铁和磷吸收及其分布的影响

本文研究外源锰有效性对大豆生长和锰、铁、磷吸收及其分布影响的结果表明,在锰缺乏和锰浓度超过50μmol·L-1的处理条件下,大豆生长受到明显抑制。随着外源锰浓度增加,大豆体内,尤其在老叶中锰浓度显著增加。锰和铁之间存在一定的拮抗作用。缺锰和锰毒不影响大豆对磷的吸收。但是,缺锰显著影响磷在老叶和新叶中的分配。     

缺铁胁迫对小豆幼苗生理特性的影响

为了探讨小豆铁高效的生理指标,研究缺铁胁迫对小豆(Vigna angularisi)幼苗主要生理特性的影响。选取4个小豆材料(13MY001、13MY007、FMY020及JN6)幼苗,采用溶液培养方法,设置Fe(Ⅱ)-EDTA浓度为0 mol/L、4×10-5 mol/L两组处理,分别于处理后7、14、21 d对其相关指标进行测定分析。结果表明,缺铁胁迫降低了小豆幼苗叶片的叶绿素含量及光合速率,增加了小豆幼苗根系呼吸速率及Fe3+还原酶活性,并且在+Fe和-Fe处理间差异达显著水平(P0.05);不同小豆品种(品系)间的上述指标均存在显著差异。综合分析得出,小豆的幼苗叶片的叶绿素含量、光合速率及根系Fe3+还原酶活性、根系呼吸速率可作为筛选、培育铁高效小豆品种的生理指标。     

锰胁迫对盐肤木种子萌发、幼苗生长及理化特性的影响

为揭示植物适应锰胁迫的生理机制,通过在不同Mn²⁺浓度(0、1、5、10、15、20 mmol/L)下开展盐肤木(Rhus chinensis)种子萌发以及幼苗生长实验,检测锰胁迫处理7、15、30 d后幼苗生理生化特性的变化。结果表明:(1)随着Mn²⁺浓度的升高,盐肤木种子发芽率变化不显著,在80.0%-81.6%之间,发芽势、发芽指数和活力指数则呈先升后降的趋势;其幼苗生物量也呈现先升后降的趋势;(2)随着Mn²⁺浓度的升高与胁迫时间的延长,盐肤木幼苗叶绿素a、叶绿素b含量均呈现先增加后降低的趋势,类胡萝卜素含量呈现下降的趋势;(3)胁迫7 d时,随着Mn²⁺浓度的升高,盐肤木幼苗超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性均显著上升;胁迫15、30 d时,高Mn²⁺浓度(15-20 mmol/L)下POD、CAT活性则均降低;(4)胁迫7 d时,随着Mn²⁺浓度的升高,可溶性糖、可溶性蛋白、游离脯氨酸含量升高;胁迫15、30 d时,在Mn²⁺浓度为20 mmol/L时可溶性蛋白与游离脯氨酸含量显著降低;(5)随着Mn²⁺浓度的升高与胁迫时间的延长,丙二醛(MDA)含量均升高。研究说明盐肤木具有较强的耐受锰胁迫能力,它可通过增强抗氧化酶活性、积累渗透调节物质含量来应对锰胁迫。     

锰胁迫对杠板归细胞超微结构的影响

锰是植物生长必需的微量元素,然而锰含量过高将影响酶活性、造成植物毒害,不同植物的锰耐性差异很大。杠板归(Polygonum perfoliatum L.)是一种生长在锰尾矿废弃地的耐性植物。通过温室培养,应用透射电子显微镜-能谱联用仪研究不同锰处理条件下(5,1000,10 000μmol/L)杠板归根、茎和叶细胞超微结构的变化和锰在叶细胞内可能的存在形式,结果表明:(1)生长介质锰含量为5μmol/L时,杠板归细胞超微结构未见异常;即使锰处理浓度为1000μmol/L时,杠板归根、茎和叶细胞结构依然完整,细胞器清晰可见,未见明显损伤;(2)当锰处理浓度为10000μmol/L时,杠板归细胞器未见缺失现象,但根细胞内线粒体数量减少,茎细胞叶绿体开始受损,叶细胞叶绿体膜结构出现破损,基粒片层结构减少,嗜锇颗粒数量明显减少;(3)与对照相比,1000μmol/L或10000μmol/L锰处理30 d,植物细胞内出现黑色团聚物。10000μmol/L锰处理条件下,杠板归叶细胞内和细胞间隙出现类似针状物质,这可能是杠板归体内锰积累和分布的形态之一。研究成果有助于阐明植物的锰耐性机制,为锰耐性植物筛选和废弃锰尾矿库生态重建提供科学参考。     

水稻苗期低温失绿的遗传分析及基因定位

在早季低温条件下, 籼稻品种Dular的幼苗表现出白化失绿, 而粳稻品种Lemont幼苗表现正常绿色。以Lemont和Dular作亲本构建一个F2群体,通过该群体在早季低温条件下性状的表现,发现Lemont和Dular苗期耐冷性的差异受单个主基因控制,低温下白化失绿等位基因为隐性。将该基因暂时命名为cisc(t)。利用该F2群体,采用集团分离分析(BSA)法将cisc(t)定位在9号染色体上。经过对F2群体中100个典型的白化单株的简单序列长度多态性分析,将该基因定位在5.5 cM的区间内,分别与微卫星标记RM257和RM242相距3.9 cM和1.6 cM。     

水稻温敏型突变体叶片间断失绿的超微结构

在短时降温诱导下,水稻温敏型突变体１１０３ｓ（Ｏｒｙｚａ　ｓａｔｉｖａ　ｓｓｐ．ｉｎｄｉｃａ）植株间断失绿性状表达（临界温度２３．１℃）过程中,叶绿体含量的增减与叶色变化相符。电镜观察发现,性状表达时叶片间断失绿区叶绿体内部结构发生退化,呈现基粒垛叠片层数的异常减少,或基粒消失仅剩基粒残迹,有的甚至整个叶绿体为高电子密度的囊泡状结构。但在同一叶片的绿区,叶绿体仅表现基粒片层数减少、排列不规则,嗜锇小球聚集。在叶片失绿区的复绿过程中,叶绿体的这些变化又可逆转,内部结构重建,最后整个叶绿体结构基本恢复正常。水稻温敏突变体１１０３ｓ叶片间断失绿性状表达过程,实质上是一个由温度调控的叶绿体结构退化与修复的可逆过程。     

Genetics of tolerance to iron chlorosis in rice

Genetics of tolerance to iron chlorosis was investigated in eight crosses involving parents distinctly different in their level of tolerance. The segregating populations with parents and F₁s were screened under actual stress conditions in the field. Also, selected crosses were studied for Fe³⁺ uptake capacity. Tolerance/moderate tolerance to Fe chlorosis was dominant over susceptibility and it was controlled by two sets of nonallelic genes with complementary interaction. Gene Ic ₁ has been found to be basic and in complementation with Ic ₃ it confers tolerance. Likewise, Ic ₂ with Ic ₄ confers tolerance. The basic genes Ic ₁ and Ic ₂ are nonallelic and, in the absence of their respective complementary genes Ic ₃ and ₄ , ineffective, which results in susceptibility. Of tolerant cultivars, ARC 10372 and Cauvery have been tentatively assigned the genotype of Ic ₁ , Ic ₂ , Ic ₃ , Ic ₄ , and moderately tolerant IET 7613, Prasanna and Akashi Ic ₁ , ₂ Ic ₃ Ic ₄ . The susceptible ARC 5723 has been assigned Ic ₁ , ₂ , Ic ₃ , Ic ₄ , and IET 9829, Ic ₁ , ₂ Ic ₃ Ic ₄ . IET 7614 is susceptible, due to the presence of inhibitory genes I-Ic ₁ , I-Ic ₂ together with ic ₁ pt>, ic ₂ , Ic ₃ , Ic ₄ . Further, the gene Pc for purple coleoptile shows linkage with one of the complementary genes with a crossover value of 15.26%, while the gene(s) for seedling height Ts with Ic ₁ with a crossover value of 1.7%. It is possible that the gene(s) for iron chlorosis tolerance might belong to the second linkage group, where genes for purple leaf were located.     

Iron availability in plant tissues-iron chlorosis on calcareous soils

The article describes factors and processes which lead to Fe chlorosis (lime chlorosis) in plants grown on calcareous soils. Such soils may contain high HCO₃ ^- concentrations in their soil solution, they are characterized by a high pH, and they rather tend to accumulate nitrate than ammonium because due to the high pH level ammonium nitrogen is rapidly nitrified and/or even may escape in form of volatile NH₃. Hence in these soils plant roots may be exposed to high nitrate and high bicarbonate concentrations. Both anion species are involved in the induction of Fe chlorosis.Physiological processes involved in Fe chlorosis occur in the roots and in the leaves. Even on calcareous soils and even in plants with chlorosis the Fe concentration in the roots is several times higher than the Fe concentration in the leaves. This shows that the Fe availability in the soil is not the critical process leading to chlorosis but rather the Fe uptake from the root apoplast into the cytosol of root cells. This situation applies to dicots as well as to monocots. Iron transport across the plasmamembrane is initiated by Fe^III reduction brought about by a plasmalemma located Fe^III reductase. Its activity is pH dependent and at alkaline pH supposed to be much depressed. Bicarbonate present in the root apoplast will neutralize the protons pumped out of the cytosol and together with nitrate which is taken up by a H⁺/nitrate cotransport high pH levels are provided which hamper or even block the Fe^III reduction.Frequently chlorotic leaves have higher Fe concentrations than green ones which phenomenon shows that chlorosis on calcareous soils is not only related to Fe uptake by roots and Fe translocation from the roots to the upper plant parts but also dependent on the efficiency of Fe in the leaves. It is hypothesized that also in the leaves Fe^III reduction and Fe uptake from the apoplast into the cytosol is affected by nitrate and bicarbonate in an analogous way as this is the case in the roots. This assumption was confirmed by the highly significant negative correlation between the leaf apoplast pH and the degree of iron chlorosis measured as leaf chlorophyll concentration. Depressing leaf apoplast pH by simply spraying chlorotic leaves with an acid led to a regreening of the leaves.     

Interactions between iron-deficiency chlorosis and soybean cyst nematode in Minnesota soybean fields

Experiments were conducted in four commercial fields differing in severity of iron-deficiency chlorosis (IDC), and soybean cyst nematode (SCN) in Waseca and Lamberton, Minnesota to determine the interaction between the IDC and SCN. Each experiment was a randomized complete block with a factorial treatment design including 23 cultivars with or without traits of resistance to SCN, and IDC. The study illustrated the interactive effects of the two defensive traits on the diseases and soybean yields. IDC rating was higher in SCN-susceptible than SCN-resistant soybean, suggesting SCN infection increased IDC. Resistance to IDC apparently increased SCN reproduction due to better soybean plant growth. Yield response to the defensive traits depended on the disease pressures in a field. When both IDC and SCN were present in a field, deploying SCN-resistance was the best solution to the problems. However, SCN-resistance suppressed soybean yields when used in fields without the disease problems. IDC-resistance increased yield of SCN-susceptible cultivars, but it did not result in detectable yield benefit of SCN-resistant cultivars in SCN-infested sites. Effective use of the defensive traits for management of IDC and SCN requires specific knowledge of the disease problems present in a field. Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the U. S. Department of Agriculture and the University of Minnesota.     

石灰性土壤上HCO3-诱导花生缺铁失绿机制

采用土壤-营养液结合的分根培养方法,研究了部分根系供应HCO- 3或铁对花生铁营养的调控及其作用机制。结果表明,对花生部分根系供应HCO- 3或铁可以调控花生的铁营养,仅供HCO- 3可以诱导缺铁,而只供铁能矫正失绿,同时供应HCO- 3和铁时则不引起失绿。在花生新生叶失绿和复绿的过程中,其中的活性铁含量和全铁含量也有相应的消长。当花生表现缺铁失绿症状时,地上各部分的全铁含量显著降低,而土中根的全铁含量不降低、质外体铁含量升高。在HCO- 3存在的条件下,不同部分根系的铁( )还原酶活性因其生长介质而不同,营养液中根系的铁( )还原酶活性降低而土中根的铁( )还原酶活性不受影响。当花生表现缺铁失绿症状时,土壤中HCO- 3含量升高,有效铁含量不高,p H值无变化。因此,本试验证实了石灰性土壤上的高HCO- 3含量,主要是降低了花生地上部的铁含量而引起失绿,而且花生缺铁失绿又导致土壤HCO- 3含量升高     

Varietal response to iron chlorosis in upland rice

Summary In a study involving twenty upland rice genotypes, the induction of iron chlorosis was found to be more by superphosphate application than due to lime incorporation into an alfisol soil under greenhouse conditions in GI tray-grown seedlings as quantified by two parameters viz., total chlorphyll content and Fe²⁺ content. Of the two indices of iron chlorosis, Fe²⁺ was more sensitive than chlorophyll content. Genotypes were grouped into efficient and inefficient categories both in terms of absorption and utilization of iron based on the degree of reduction in response to added superphosphate.     

Long-term effectiveness of vivianite in reducing iron chlorosis in olive trees

Iron (Fe) chlorosis is common in olive (Olea europaea L.) trees growing on highly calcareous soils in Southern Spain, where generally causes reduction in yield, size and commercial value of the olives. The objective of this research was to study the effectiveness of synthetic vivianite (Fe₃(PO₄)₂H₂O) to reduce Fe chlorosis in olive. Experiments were established in three orchards with cultivars `Hojiblanco', `Manzanillo', and `Picual'. The design was a randomised block design with two or three treatments (control with no Fe fertiliser and vivianite at one or two rates). A vivianite suspension (0.05 kg dm<sup>–3</sup> water) was injected into the soil at 10–20 points around the tree at the depth of maximum root density (25–35 cm). The rates (and times of application) were 0.5 and 1 kg tree<sup>–1</sup> for `Hojiblanco' (March 1997), 1 kg tree^–1 for `Manzanillo' (March 1998), and 2 kg tree<sup>–1</sup> for `Picual' (March 1998). The leaf chlorophyll content index (CCI) was estimated on the youngest expanded leaves by means of a Minolta apparatus (SPAD units). The colour index of the olives was estimated by visual comparison with a scale ranging from 1 (pale yellow) to 8 (normal green). For the period studied (July 1997–November 1999), the CCI of fertilised trees was, in general, significantly higher than that of control trees, and so was the case with the olive colour index. Olive yield, measured in the experimental fields with `Hojiblanco' (in 1999) and `Manzanillo' (in 1998 and 1999), was higher for the fertilised than for the control trees but differences were only significant in 1999. These results suggest that vivianite is effective to reduce Fe chlorosis for more than two seasons. Such effectiveness is probably due to the poorly crystalline Fe(III) oxides (which are good sources of Fe to plants) that result from the slow oxidation and incongruent dissolution of vivianite.     

Effect of prevention of iron chlorosis on the quality of sugarcane grown on vertisols

Results of a field experiment comprising various sources of sulphur and iron showed that band application of sulphur @ 500 kg/ha significantly increased the mean sugar content by 5.6%, recovery of sugar by 5.8% and purity of sugarcane juice by 0.8% on account of increased leaf sulphur content as compared with that under control. The application of Fe-EDDHA or gypsum had little effect on the quality of sugarcane juice. Effect of ferrous sulphate was intermediate between that of sulphur and gypsum. A study of the relationship between sulphur content of leaves and juice characteristics showed that every 1% increase in sulphur content of leaves increased sugar content in cane juice by 0.038%, recovery of sugar by 0.038% and purity of juice by 0.033%.     

马尾松幼苗生理指标对高锰胁迫的响应

采用砂培方法,在温室内研究了马尾松1年生苗木在不同锰浓度(0.005(对照)、1、5、10和15mmol·L-1)条件下的生理指标响应。结果表明:与对照相比,高锰浓度(≥10mmol·L-1)下马尾松的生物量和根系活力降低。高锰条件下,马尾松针叶中叶绿素a、叶绿素b、类胡萝卜素含量下降,表明锰对马尾松光合机构存在一定影响,同时也是导致生物量降低的原因之一。在高锰胁迫下,丙二醛(MDA)含量以及超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性均发生显著变化且对锰毒起到一定的缓解作用,其中CAT和MDA对高锰胁迫的响应比较灵敏,MDA和2种酶的变化反映了马尾松对高锰胁迫的生理响应。     

Relationship between iron chlorosis and alkalinity in Zea mays

Mengel, K. and Geurtzen, G. 1988. Relationship between iron chlorosis and alkalinity in Zea mays . - Physiol. Plant. 72: 460–465.
Maize ( Zea mays L. cv. Anjou 21) grown in nutrient solution with Fe-EDTA and with nitrate as the sole nitrogen source showed typical Fe-chlorosis symptoms after a growth period of 14–21 days. Alkalinity in roots, stems and leaves of the chlorotic plants was high. Transferring the chlorotic plants from the nitrate-containing nutrient solution to a solution of (NH₄)₂SO₄ resulted in a regreening of leaves within 2–3 days which was associated with a decrease in solution pH, a decrease in alkalinity of plant parts, a translocation of Fe from roots to tops and a release of Fe into the outer solution. Similar effects were obtained when Fe chlorotic plants were transferred to a dilute HO solution with pH 3.5.
Spraying chlorotic leaves with indoleacetic acid or with fusicoccin led also to a regreening of leaves without having a major effect on leaf alkalinity.
Interpretation of the experimental results is based on the assumption that nitrate as sole N source leads to a high pH level in the apoplast resulting in the precipitation of Fe compounds, probably Fe oxide hydrate. Ammonium nutrition has the reverse effect since it lowers the apoplast pH and this can result in the dissolution of Fe compounds. Application of indoleacetic acid as well as fusicoccin supposedly stimulates the proton pumps in the plasmalemma of the leaf tissue. The resulting decrease in apoplast leaf pH in the microenvironment also leads to a dissolution of Fe compounds in the apoplast and thus promotes the uptake of Fe by the symplasm.