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1.
The production of secondary metabolites by plants growing in natural populations is conditioned by environmental factors. In the present study, we have investigated the relationships among soil properties, micronutrients in soils and plants, and cardenolide production from wild Digitalis obscura (Scrophulariaceae) populations. Young and mature leaves and soil samples were collected in ten different populations, corresponding to three Mediterranean bioclimatic belts (Thermo‐, Meso‐, and Supramediterranean belts). Soil (total and EDTA‐extractable) and leaf micronutrients (Fe, Mn, Zn, and Cu), and leaf cardenolide accumulation have been determined. Significant negative correlations were observed between Fe, Mn or Zn concentration in leaves and soil pH, as well as between Fe or Mn in leaves and carbonate content of soils. Only EDTA‐extractable Mn was significantly correlated with Mn content in the plants. With regard to cardenolide content in leaves, this parameter was negatively correlated with Znleaf in young leaves and with Mnleaf in old leaves. Positively correlated, however, were Fe and cardenolide content in young leaves. The influence of environmental conditions and leaf micronutrient contents on cardenolide accumulation is discussed.  相似文献   

2.
For dicots, bicarbonate (HCO3‐) is regarded as a main factor in the induction of iron (Fe) chlorosis in calcareous soils, and sand and solution culture. In sand culture experiments, peach [Prunus persica (Batsch) L.] rootstock developed chlorosis only when HCO3‐ levels were equal to or higher than 6 mM. Above this level, chlorosis increaeed as HCO3‐ level was increased. In spite of the lack of chlorosis at to or below 6 mM of HCO3‐, large growth reductions (40–60% reduction in fresh shoot weight) were seen in all rootstocks, although the tolerant rootstock had less reduction than the more susceptible rootstocks. Shoot growth was affected by HCO3‐ more than was root growth.  相似文献   

3.
Reasons for chlorosis of vine (Vitis vinifera L.) under field conditions
  • 1 Analysis of leaf and soil samples from green and chlorotic vineyards did not result in a clear correlation between chlorosis and one of the soil factors determined (pH, concentration of HCO3?, water soluble P, DTPA-extractable Fe, Mn, Zn, Cu).
  • 2 In severe chlorotic leaves the concentration of all elements investigated was increased, while in weak chlorotic leaves the concentration of Fe, Mn, Zn, Cu and P stayed unchanged.
  • 3 There was no change neither in the P: Fe nor in the K: Ca ratio of the leaves due to chlorosis, but significant differences existed in the ratio extractable Fe: total Fe and total P: extractable Fe between green and chlorotic leaves.
  • 4 The increased amount of Mn and Zn in severe chlorotic leaves reached a 100 %, the also increased amount of Fe only a 20% extractability by 0,5 n HCl, which together with the high P-concentration can be assumed as a main reason for chlorosis.
  相似文献   

4.
A hypothesis has been presented and tested that bicarbonate (HCO3) and nitrate (NO3) are the most important anions inducing iron (Fe) chlorosis because these anions increase the pH of leaf apoplast which in turn depresses ferric‐iron [Fe(III]) reduction, and hence, the uptake of Fe into the symplasm. Experiments with young sunflower (Helianthus annuus) plants showed that nutrition with NO3 as the sole nitrogen (N) source induced chlorosis whereas ammonium nitrate (NH4NO3) did not. Monohydrogen carbonate (bicarbonate) also favoured the development of chlorosis. The degree of chlorosis was not related to the Fe concentration in the leaves. Both anion species, NO3 and HCO3, increased the pH of the leaf apoplast which was measured by means of the fluorescence dye 5‐carboxyfluorescein. A highly significant negative correlation between leaf apoplast pH and chlorophyll concentration in the leaves (r = ‐0.97) was found. Ferric‐Fe reduction in the apoplast—measured by means of ferrocene—provided evidence that a low leaf apoplast pH, obtained with ammonium (NH4) supply, favoured the reduction of Fe(III) as compared with a higher leaf apoplast pH obtained with NO3 supply. These results support the hypothesis tested.  相似文献   

5.
This study was conducted to compare the most appropriate method for the evaluation of available iron (Fe) status of calcareous soils by using nine different chemical extraction methods. Leaf and soil samples were collected from nine peach (Prunus persica L.) orchards, each of which included green, slightly chlorotic, and severely chlorotic peach trees. According to the chlorosis degrees of the leaves, total and active Fe contents and some soil properties were determined. Relationships between these parameters and Fe amounts obtained from the methods were correlated. Among the methods tested, method 3 (M3) [0.05 N hydrochloric acid (HCl) + 0.025 N sulfuric acid (H2SO4)] and method 8 (M8) 0.05 M ethylenediaminetetraacetic acid (EDTA) (pH 7.0) were the most suitable methods to indicate the available Fe status of the soils.  相似文献   

6.
A survey was conducted in order to estimate micronutrient levels in plants and soils of 215 farms in Greece cultivated with sugar beet. Soils were analyzed for particle-size distribution, pH, organic carbon (C), CaCO3, and DTPA-extractable copper (Cu), zinc (Zn), iron (Fe), and manganese (Mn). Sugar beet leaves were analyzed for the same metals. Also, aboveground biomass (top), root, and raw sugar yields were recorded. DTPA-extractable Fe and Mn were above critical levels in all cases, whereas Cu and Zn were above critical levels in 49% and 24% of the soil samples, respectively. Concentrations of the four metals in plant tissue were similar or higher than the sufficiency range. Concentrations of DTPA-extractable Fe and Mn, and plant Zn and Mn, were significantly and negatively correlated with soil pH. Soil pH and DTPA-extractable Fe seemed to have a significant positive impact on root, top, and raw sugar yields. However, in all cases, less than 14% of the variance of the sugar beet parameters was explained by soil characteristics.  相似文献   

7.
Peanut (Arachis hypogea cv. Shulamit) grown on very high calcium carbonate (CaCO3) content soils is showing iron (Fe) chlorosis symptoms. Supplying the plant with ammonium sulphate ((NH4)2SO4) in the presence of nitrapyrin (N‐Serv) for preventing nitrification reduced Fe chlorosis. Nitrate (NO‐ 3) developed in the soil with time, even with nitrapyrin present. When ammonium (NH+ 4) was even less than 20% of the total mineral N in the soil, no Fe‐stress could be observed, suggesting that the NH+ 4 uptake by the plant and the consequence of hydrogen (H+) efflux occurs from the root to the rhizosphere, resulting in a decrease of redox potential near the root, and solubilizing enough Fe near the root to overcome the chlorosis.  相似文献   

8.
Distribution of iron in vine leaves with HCO3? induced chlorosis The distribution of Fe in chlorotic and healthy leaves of grapevine has been studied. Application of HCO3? had no significant influence on the long distance transport of labelled Fe, the translocation of Fe from the vascular tissue to the intercostal cells (cells between leaf veins), however, was much affected by HCO3?. Leaf samples collected from three different sites showed in most cases higher Fe contents in the chlorotic leaves as compared with healthy leaves. The solubility of leaf Fe in diluted HCl, however, was lower in chlorotic leaves than in green leaves. Enzymatic dissolution of leaves into vascular tissue, intercostal cells and chloroplasts revealed that the Fe-content in the intercostal cells of green leaves was significantly higher than in the intercostal cells of chlorotic leaves. In addition the intercostal cells of chlorotic leaves had extremly high Ca and P-contents. The P content of green and chlorotic leaves was not related to the level of available P in the soil. It is therefore concluded that the high P content in chlorotic leaves is the sequence and not the cause of Fe-chlorosis. On each of the three sites investigated, higher clay contents were found under chlorotic grapevine plants than under healthy ones. It is assumed that because of this higher clay content, soil compaction may occur, resulting in an accumulation of CO2 and in an increase of the HCO3? concentration in the soil solution.  相似文献   

9.
Abstract

Iron (Fe) chlorosis, an Fe deficiency commonly observed in grapevines cultivated on calcareous soils, generally inhibits plant growth and decreases yield. The objective of this research was to relate the incidence of Fe chlorosis in vines of the Montilla‐Moriles area, southern Spain, to indigenous soil properties. Thirty‐five grapevines (V. vinífera L. cv. Pedro Ximenez grafted on V. berlandieri×V. rupestris 110 Ritcher) showing different degree of Fe chlorosis were selected from 13 vineyards. The leaf chlorophyll concentration (estimated by the SPAD value measured with a Minolta meter) was positively correlated with the contents in different soil Fe forms but not with alkalinity‐related soil properties (pH, calcium carbonate equivalent, and active lime). The acid NH4 oxalate‐extractable Fe (Feo) was the most useful simple variable to predict the occurrence of Fe chlorosis. A Feo/active lime ratio of 25×10–4 was found to be useful to class soils into two groups according to the probability of inducing Fe chlorosis.  相似文献   

10.
Studies were conducted to determine the efficacy of K salts in alleviating lime‐induced chlorosis. Greenhouse studies using a Gibbon silt loam [fine‐silty, mixed (calcareous), mesic Typic Haplaquoll] and a 1: 1 mixture of Gibbon soil and washed sand were conducted with KCl, KNO3, K2SO4, K2HPO4, or KHCO3 applied at rates of 0, 250, and 500 mg K/kg soil. An FeEDDHA treatment was included for comparison. Similar studies were conducted at two field sites known to produce lime‐induced chlorosis. Potassium salts were applied at 0, 20, and 40 g K/m of row. In the greenhouse, plants treated with KCl, KNO3, and K2SO4 on Gibbon soil were less chlorotic than controls or plants treated with K2HPO4, or KHCO3. No K treatment totally alleviated chlorosis except FeEDDHA. Chlorophyll correlated positively with chlorosis rating. No relationship was found between leaf Fe uptake and chlorosis. Plants grown in soil/sand exhibited no chlorosis and had lower Fe uptake than plants grown in Gibbon soil. Thus chlorosis was not due strictly to low soil‐Fe availability or inadequate Fe uptake. Bicarbonate in the soil solutions of both growth media treated with KCl was lower than controls which may explain the reduced chlorosis associated with this treatment.

One field site showed positive effects of K treatments on chlorosis rating, chlorophyll concentration, and seed yield. No treatment was as effective as FeEDDHA in influencing plant growth or yield. Total leaf Fe concentration was unrelated to leaf chlorophyll concentration. Inorganic cation/anion ratios in the plant were from 4.4–8.4 which could cause net H+ efflux by the plant and alkalinization of plant tissues. One possibility is that H+ efflux solubilizes P in the rhizosphere, which after uptake could immobilize Fe in the plant. Application of KCl, KNO3, and K2SO4 generally lowered HCO3 content of the upper 15 cm of both soils. High bicarbonate could increase rhizosphere P availability and increase immobilization of Fe in the plant.  相似文献   

11.
It has been proposed that glutathione can relieve the effects of Fe deficiency. This study tested the effects of glutathione foliar treatments to prevent Fe chlorosis, using as positive controls soil and foliar Fe fertilisation. Medicago scutellata plants were grown in soil (5.7% CaCO3) supplemented or not with 4 and 8% CaCO3. Two Fe(III)‐EDDHA soil treatments (5 and 10 mg Fe kg?1), and three foliar treatments (three applications each of 2.14 mM Fe(III)‐EDDHA, 1 mM glutathione, and the previous two combined) were applied. Measurements include leaf chlorophyll and Fe concentrations, biomass, leaf enzymatic and non‐enzymatic antioxidant systems and carboxylates. The addition of CaCO3 caused typical Fe deficiency symptoms, including changes in chlorophyll, Fe, antioxidant systems and carboxylates, which were prevented by soil and foliar Fe fertilisation. The foliar treatment with glutathione also led to higher chlorophyll, leaf extractable Fe and root Fe, as well as decreases in some antioxidant systems, whereas leaf Fe concentrations decreased. The combined foliar application of glutathione and Fe was even more efficient in preventing chlorosis. Including glutathione in foliar fertilisation programs should be considered as an option for Fe chlorosis prevention, especially when relatively large leaf total Fe concentrations occur in the so called chlorosis paradox.  相似文献   

12.
《Journal of plant nutrition》2013,36(10):2205-2228
ABSTRACT

Chlorosis in crops grown on calcareous soil is mainly due to iron (Fe) deficiency and can be alleviated by leaf application of soluble Fe2+ or diluted acids. Whether chlorosis in indigenous plants forced to grow on a calcareous soil is also caused by Fe deficiency has, however, not been demonstrated. Veronica officinalis, a widespread calcifuge plant in Central and Northern Europe, was cultivated in two experiments on acid and calcareous soils. As phosphorus (P) deficiency is one of the major causes of the inability of many calcifuges to grow on calcareous soil we added phosphate to half of the soils. Leaves in pots with the unfertilized and the P-fertilized soil, respectively, were either sprayed with FeSO4 solution or left unsprayed. Total Fe, P, and manganese (Mn) in leaves and roots and N remaining in the soil after the experiment were determined. In a second experiment, no P was added. Leaves were either sprayed with FeSO4 or with H2SO4 of the same pH as the FeSO4 solution. Degree of chlorosis and Fe content in leaves were determined. Calcareous soil grown plants suffered from chlorosis, which was even more pronounced in the soils supplied with P. Newly produced leaves were green with Fe spray but leaves that were chlorotic before the onset of spraying did not totally recover. H2SO4 spray even increased chlorosis. This demonstrated that chlorosis was due to Fe deficiency. As total leaf Fe was similar on acid and calcareous soil, it was a physiological Fe deficiency, caused by leaf tissue immobilization in a form that was not metabolically “active”. Iron in the leaves was also extracted by 1,10-phenanthroline, an Fe chelator. In both experiments, significant differences between leaves from acid and calcareous soil were found in 1,10-phenanthroline extractable Fe but not in total leaf Fe, when calculated on a dry weight basis. Differences in 1,10-phenanthroline extractable Fe were more pronounced when calculated per unit dry weight than calculated per leaf area, whereas the opposite condition was valid for total leaf Fe.  相似文献   

13.
Total Zn in alluvial and calcareous soils (average 138 and 70 ppm respectively) was significantly related to their contents of CaCO3 (negatively), O.M. and clay (positively). Extracting Zn by Na2EDTA gave the highest values for both soil types. Total Cu contents varied widely from 26 to 111 ppm in alluvial and from 15 to 30 ppm in calcareous soils. They were negatively correlated with the CaCO3 contents. The pot experiments showed that EDTA(NH4)2CO3, Na2EDTA and DTPA are reasonable extractants for available Zn from both soil types. DTPA was efficient for all soils investigated, while Na2 EDTA and EDTA-citrate were specific for extracting Cu from calcareous soils.  相似文献   

14.
Abstract

Plant growth is frequently limited by Fe‐related chlorosis on calcareous soils and by mineral toxicities on strongly acid soils and mine spoils. Better adapted varieties are needed for both soil situations, which are not always economically correctable. In a search for such geraplasm, 4 species (20 accessions) of Eragrostis were grown in greenhouse pots of a calcareous soil at pH 7.3. Two species were also compared on acid mine spoil at pH 3.5 and 4.7.

Species, and accessions within species, differed significantly in tolerance to the calcareous soil, as measured by susceptibility to chlorosis and yield of plant tops. The range in top yield was 11‐fold for accessions of Eragrostis capensis, 3‐fold for Eragrostis lehmanniana, and 1.7‐fold for Eragrostis superba. Eragrostis plana (P.I. 364340) was more tolerant to acid mine spoil (pH 3.5) but less tolerant to calcareous soil (pH 7.3) than Eragrostis superba (P.I. 364833).

Chlorosis and poor growth of certain accessions on calcareous soil (pH 7.3) were not explained by specific mineral deficiencies or toxicities. However, the tops of chlorosis‐susceptible accessions had lower ratios of Fe/Mn, Fe/Zn, and Fe/Cu than those of chlorosis‐resistant accessions. This imbalance is believed to interfere with Fe metabolism in plant tops.

Results suggested that superior strains of Eragrostis species can be selected for adaptation to calcareous or acid soils and that certain accessions characterized in these studies can be useful in studying the physiological mechanisms of mineral stress resistance in plants.  相似文献   

15.
《Journal of plant nutrition》2013,36(10-11):2057-2068
Abstract

Pellitory of the wall (Parietaria diffusa L.), a dicotyledonous wild plant belonging to the family of Urticaceae, is widespread on calcareous soils, and also on walls and debris, were lime concentration, sometimes, is extremely high; it may then be considered a calcicole plant. Since high pH values and the presence of CaCO3 and HCO3 ? cause low Fe solubility, its availability in such substrates could be the ecological factor limiting the distribution of spontaneous plants in calcareous soils, and a calcareous soil‐born plant should be characterized by a higher Fe‐efficiency in comparison with calcifuge ones. Parietaria diffusa was grown in nutrient solutions in the presence and in the absence of Fe, and in the presence of CaCO3 and bicarbonate at two concentrations (5 and 15 mM), in order to simulate a natural substrate with different lime contents. Some biochemical parameters were determined and the morphological and hystological modifications of the root system were evaluated in order to verify whether Parietaria is a Fe‐efficient plant and adopts the adaptive mechanisms of Strategy I Fe‐efficient plants.  相似文献   

16.
Abstract

The effect of salinity in inducing soil macro and micronutrient deficiencies that can decrease crop growth was evaluated in a corn (Zea mays L.) field located in east central Wyoming. In this study water soluble Na was found to be a better predictor of salinity than pH and other cations. Soil saturated paste extracts had electrical conductivities that were negatively correlated with soil total K, Cu, Fe, and Mn. Total N, NO3‐N, PO4‐P, Zn, pH, and water soluble Na, Ca, and Mg of the soil were positively correlated with EC. Significant positive relationships existed between soil EC and N, P, Mo, and Zn, and negative relationships with K, Cu, Fe, and Mn of corn leaves and kernels. Concentrations of nutrients in the kernels were positively correlated with corresponding nutrient concentrations in the leaves and with AB‐DTPA extractable soil nutrients. The analysis of variance of EC data indicated that soil samples possessing high salinity were higher in pH and contained significantly higher soluble Na, Ca and Mg, total N, N03‐N, PO4‐P, and Zn and significantly lower Mn compared to samples having low salinity. The kernel weight per cob and plant height were significantly reduced as salinity increased.  相似文献   

17.
In the present study, Olsen [0.5 M sodium bicarbonate (NaHCO3), pH 8.5] and resin–bicarbonate (HCO3) tests underestimated available phosphorus (P) in calcareous soils treated with gypsum (CaSO4). The reaction of CaSO4 and HCO3 ? ion or resin–HCO3 to form calcium carbonate (CaCO3) precipitate reduced the strength of the Olsen NaHCO3 extractant and resin–HCO3 strip for P extraction. The iron (Fe) oxide–impregnated filter paper (Pi strip) was independent of CaSO4 influence and thus correctly estimated soil‐available P with respect to plant response to soil‐available P. Two greenhouse experiments were conducted with maize and wheat grown on calcareous soils treated with different rates of CaSO4. The results confirmed that Olsen and resin–HCO3 tests should not be used to measure available P or labile P in the P fractionation scheme in the calcareous soils containing significant amounts of gypsum.  相似文献   

18.
Abstract

The major purpose of these experiments was to determine if Pb uptake by plants was significantly increased by chelating agents used in plant nutrition. The interaction of Pb with some other elements in barley plants (Hordeum vulgare L. C.V. Atlas 57) and bush bean (Phaseolus vulgaris L. C.V. Improved Tendergreen) was studied in a glasshouse with different rates of Pb in solution culture and in amended (control, S, CaCO3, MgCO3) Yolo loam soil with and without the chelating agent DTPA (diethylene triamine pentaacetic acid). In a solution culture experiment, 10‐3 M Pb significantly decreased bush bean yields in both control and DTPA treatments. The CaCO3 added to nutrient solution decreased the concentration of Pb in leaves, stems, and roots and prevented the toxicity of 10‐3 M Pb++. At high Pb levels, interactions between Pb and Mn and Pb and Fe were observed, except with CaCO3. In the soil experiment, the yields of barley and bush bean were influenced only slightly by Pb. The Pb concentration in barley shoots and bush bean leaves and stems was increased considerably in the presence of DTPA, however. In the absence of DTPA, the effect of added Pb was very small in the control and S amended soil treatments and almost negligible in the CaCO3 and MgCO3 amended soil treatments. Application of DTPA facilitated the translocation of Pb, Fe, Mn, Cu, and Zn to shoots. The effect was dependent upon soil pH. Particularly, the Fe was increased by DTPA at low pH while the effect was negligible at high pH. This was opposite the effect on Pb. The DTPA resulted in considerable Pb transport to leaves and stems at high soil pH. The uptake pattern of Zn and Cu was similar to that of Pb. It can be expected that chelating agents can increase the migration of Pb to plants andincrease its uptake by plants, and hence, entry into food chains.  相似文献   

19.
Several interelemental relationships have been examined in field‐cultivated wheat (Triticum aestivum L. cv Vergina) growing on naturally enriched copper (Cu) soils. Mean soil Cu concentration per site ranged from 103–394 μg.g‐1 dry weight (DW). Interrelationships between Cu, iron (Fe), calcium (Ca), potassium (K), zinc (Zn), lead (Pb), and magnesium (Mg) concentrations in the soil and plant tissue (roots, stems, and leaves) were examined using Principle Components Analysis. Soil samples were clustered according to collection site and were primarily differentiated according to their Cu concentrations. Soil Cu concentrations were positively correlated with Zn, Ca, Fe, and K in the soil, with Cu, K, and Ca in the roots, and Cu and Fe in the leaves and negatively correlated with Fe in the roots. The increase in Cu in the roots and leaves was positively correlated with increases in K and Ca in the roots and Fe and Ca in the leaves, but negatively with Fe in the roots. Increases in leaf Ca concentrations were correlated with increases in Mg and decreases in Zn concentrations in the leaf. Plants growing in soil with high Cu concentration exhibited toxicity symptoms with reduced height, decreased total leaf area and lower chlorophyll concentrations. Photosynthesis expressed per unit leaf area was not affected by increasing Cu concentrations in the soil or plant tissue.  相似文献   

20.
Abstract

The effects of various soil properties on ammonia (NH3) volatilization from soils treated with urea were studied by measuring the NH3 evolved when 20 soils selected to obtain a wide range in properties were incubated at ‐0.034 mPa soil moisture potential and 30°C for 10 days after treatment with urea. The nitrogen (N) volatilized as NH3 from these soils represented from 0 to 65% of the urea‐N applied and averaged 14%. Simple correlation analyses showed that loss of NH3 was negatively correlated (P<0.1%) with cation‐exchange capacity, silt content, and clay content and was positively correlated (P <0.1%) with sand content. Loss of NH3 was also negatively correlated with total nitrogen content (P<1.0%), organic carbon content (P<1.0%), hydrogen ion buffering capacity (P<5.0%), and exchangeable acidity (P<5.0%), and was positively correlated with calcium carbonate equivalent (P <1.0%) and with soil pH after incubation with urea (P<1.0%), but was not significantly correlated with initial soil pH or soil urease activity. Multiple linear regression analyses indicated that the amount of urea N volatilized as NH3 from the 20 soils studied increased with increase in sand content and decreased with increase in cation‐exchange capacity. They also indicated that soil texture and cation‐exchange capacity are better indicators of potential loss of urea N as NH3 from soils fertilized with urea than are hydrogen ion buffering capacity or initial soil pH.  相似文献   

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