Soil zinc and pH effects on zinc concentrations of corn plants

Abstract

Z1nc (Zn) deficiency of corn (Zea mays L.) has been detected in 20 or more states 1n the United States including Georgia. Since soil pH is a major factor in assessing the availability of soil Zn, this measurement has been included with acid extractable soil Zn in developing calibration Zn soil tests in North Carolina and Virginia. The objectives of this study were to develop a reliable soil test for Zn based on soil pH and Mehlich 1 soil Zn for corn gown on coarse‐textured soils and to compare our soil test values with those recently published from North Carolina where Mehlich 3 was the extractant. The study was conducted 1n 1979 to 1981 on a Tifton loamy sand (Plinthic Paleudult) site which had been used to study the influence of lime rates on micronutrient availability since 1970. Treatments consisted of four soil pH levels ranging from 5.3 to 6.6 and soil Zn levels ranging from 0.5 to 4.9 mg/kg. The Zn levels were established from the previous study where 5.6 kg Zn/ha had been applied annually for eight years (residual treatment) and by applying 3.36 or 6.72 kg Zn/ha during 1979, 1980 and 1981.

Soil Zn, corn shoot, and ear leaf Zn values were reflective of the amount of Zn applied except that the residual Zn treatment resulted in Zn concentrations > than the annual application of 3.36 kg Zn/ha. Zinc tended to accumulate in the soil and in corn leaf tissue more from the residual Zn than the recently applied Zn treatments, especially at the highest pH levels. Increasingly more soil Zn was required to increase corn shoot and ear leaf Zn one mg/kg as soil pH increased. In the initial year, each unit (kg/ha) of applied Zn increased corn shoot Zn approximately 4 units (mg/kg) at pH 5.3 and only 0.3 unit at pH 6.6. Zinc deficiency symptoms developed in corn shoots for the two highest soil pH levels in two of three years. Corn yields were increased by Zn only in 1980 and were increased by residual or applied Zn at pH levels of 6.2 and 6.6. Regression equations from these studies were utilized to develop predictive corn shoot and ear leaf Zn values over wide ranges in soil Zn and pH. Our field research data using Mehlich 1 extractant could possibly be used satisfactorily in North Carolina regression equations where Mehlich 3 was the extractant; however, certain limitations would need to be imposed in the North Carolina equations.     

Use of routine soil tests in predicting corn leaf zinc

Abstract

Zinc of index corn leaves samples from 91 Minnesota sites on numerous soil types was correlated with soil Zn extracted by four routine procedures. The EDTA?(NH₄)₂CO₃ ‐ extractable soil Zn was more closely correlated with leaf Zn than soil zinc extracted by 0.1N HCl, EDTA‐NH₄OAc, or by NH₄OAc ‐ dithizone. Soil pH, CaCO₃ equivalent, extractable P, and organic matter of both acid and calcareous soils were negatively correlated with leaf Zn. When EDTA ? (NH₄)₂CO₃ ‐ extractable Zn was included with routine soil tests, a prediction equation for corn leaf Zn was formulated and compared with analytical values. However, the use of 1.4 ppm EDTA ? (NH₃)₂CO₃, ‐ extractable soil Zn alone as a critical value was equally effective in predicting leaf Zn.     

Soil fumigation effects on growth and phosphorus uptake by corn

Abstract

Phosphorus uptake rate, plant top weight, and grain yield were measured for corn (Zea mays L.) planted in field plots with or without fumigation, with different levels of P fertilization, and under conventional till and no till management. Plant growth and grain yield in P‐deficient, unfumigated conventional till and no till plots were significantly higher than those in the corresponding fumigated plots. The heightened responses were attributed to enhancement of P uptake by biological activity. Therefore, the effect of differential microblal activity on P uptake must be considered in estimating the lowest level of P fertilization needed for adequate growth in low P soils.     

不同水分状况下施锌对玉米生长和锌吸收的影响

选择潮土(砂壤)和土(粘壤)两种质地不同的土壤,进行盆栽试验,研究不同土壤水分条件下施锌对玉米生长和锌吸收的影响。结果表明,施锌显著增加了玉米植株根、茎、叶以及整株干物质重;缺锌条件下玉米植株根冠比、根叶比和根茎比趋向增大。施锌显著提高了玉米植株各器官中锌的浓度和吸收量,并明显促进锌向地上部运移。干旱胁迫抑制了玉米植株生长,根冠比、根茎比、根叶比增大;随着土壤水分供应增加,植株生长加快,各器官生物量以茎和叶增加大于根。水分胁迫下,在潮土上玉米叶片中锌浓度上升;在土上叶片中锌浓度下降。但增施锌后,根和茎锌浓度增加幅度较大,叶片增加幅度较小;施锌和水分胁迫对根和茎锌浓度的交互作用极显著。水分胁迫下,玉米植株对锌的吸收总量减少。水分胁迫和锌肥施用对玉米叶片、茎锌吸收量的交互作用十分显著,但对根锌吸收量的交互影响不显著。     

The influence op soil treatments on elemental composition of corn and on zinc soil tests on two Missouri soils

Abstract

Corn (Zea mays L) was grown at three locations on soil treated with Zn at two levels of soil fertility. Corn leaves were sampled at 2 stages of growth and analyzed for several elements. Yields were measured and soils were analyzed for O.lN HCl and DTPA extractable Zn and by standard testing methods for other components.

Zinc at 10 and 20 lb/A did not affect corn grain yields. The Zn treatments significantly increased leaf Zn concentrations. The influence of leaf sampling time differed between locations. The DTPA and O.lN HCl extractable soil Zn both reflected the Zn soil treatments. The DTPA appeared to extract a more soluble component of soil Zn which became more un‐extractable with time. In general, the extractable soil Zn was poorly correlated with Zn concentrations in the corn leaves. Under the conditions of the experiment the soil Zn levels as measured by the 2 extractants were a poor predictor of plant Zn when soil Zn levels were adequate.     

Influence of sulfur and nitrogen fertilzer on the uptake of iron,manganese, and zinc by corn plants grown in calcareous soil

Abstract

A pot experiment was conducted with a coarse‐textured calcareous soil (pH‐H₂O 8.3) to study the effect of single and combined application of N and S fertilizers on soil pH, Fe, Mn, Zn, and P mobilization, and on growth and micronutrient uptake by com (Zea mays L.). Increasing amounts of elemental sulfur were mixed with the soil. To stimulate S oxidation, the treated soils were incubated for six weeks at field capacity. Nitrogen was applied as NH₄NO₃ (100, 200, and 400 mg N/kg). After six weeks, dry matter yields were recorded and shoots were analyzed for Fe, Mn, Zn, and P. At the end of the experiment, soil pH and the DTPA‐extractable micronutrients were determined. The results showed that: a. Soil pH was decreased by 0.2, 0.5, and 0.9 unit as a result of increasing S applications.

b. Applied sulfur and N fertilizer had increased the availability of micronutrients to following crops.

c. Application of N and/or S resulted in increased dry matter yields.

d. Manganese uptake tended to be higher as amounts of N applied increased; this was most evident at the higher S application rates. This effect was, however, reversed for Fe, Zn, and P uptake.

e. Under our experimental conditions, promising results were achieved on improving micronutrient availability and uptake when 400 mg N/kg was combined with 3 g S/kg.

     

Copper and zinc uptake by celery plants grown on acidic soil amended with biosolids

For trace elements, such as copper (Cu) and zinc (Zn), the bioavailability of these elements, Cu and Zn, in biosolids is important because both are essential elements and both are potential contaminants when biosolids are land applied. A greenhouse study was conducted in factorial experiment based on a completely randomized design (CRD) with four replications on a soil treated with four rates of Cu (0, 50, 100, and 150 mg/kg) and four rates of Zn (0, 150, 300, and 450 mg/kg) on celery plants to investigate the distribution and mobility of these elements as well as growth and antioxidant changes of celery. The results of antioxidant changes were inconclusive due to irregular changes with Zn and Cu applications. However, generally the results show that Cu did not affect superoxide dismutase (SOD) or peroxidase (POD) activities in most of the treatments. On the other hand, Zn stimulated SOD and POD activities in most of the treatments. The photosynthesis rate decreased with the applications of Cu and Zn at the rates above 100 and 300 mg/kg and increased in low Cu concentration (50 mg/kg) compared to S (soil without biosolid).     

营养型土壤改良剂对酸性土壤中钾的调节及玉米吸钾量的影响

营养型土壤改良剂(以下简称改良剂)施入三种不同肥力水平的土壤进行恒温培养试验和盆栽试验,测定土壤有效钾的含量、盆栽试验玉米的生物量和钾吸收量。结果表明:对于有效钾含量高的土壤,改良剂能促进钾的缓效化,有利于土壤钾的保蓄,防止土壤钾的淋失;对于有效钾含量较低的土壤,改良剂可以活化土壤中的钾,提高土壤钾的有效性;不同肥力水平的土壤,改良剂都能促进玉米对钾的吸收,有利于提高钾肥的吸收利用效率。     

UAN氮溶液对潮土上玉米生长和氮素吸收的作用效果

为探究UAN氮溶液在潮土上对玉米生长和氮素吸收的作用效果,采用盆栽试验,研究UAN氮溶液对玉米收获期干物质积累、氮磷钾吸收量和土壤氮磷钾养分状况及pH值的影响。结果表明,等氮量的UAN氮溶液和尿素均促进了玉米的生长和对氮磷钾的吸收,两者的氮肥利用率无显著差异,分别为65.35%和64.76%。与全量UAN氮溶液相比,减施UAN氮溶液20%使玉米的生物量减少14.71%,植株中氮、磷、钾的养分吸收量分别降低24.27%、18.65%、10.47%。在低肥力潮土上,等氮量的UAN氮溶液和尿素对玉米的生长和氮素吸收的效果相当;减施UAN氮溶液20%影响玉米的生长和氮素的吸收,而氮肥利用率无明显变化。     

杂卤石对玉米生长及养分吸收的影响研究

对杂卤石作为钾肥在玉米上施用的效果进行分析,以期为杂卤石应用于农业生产提供理论依据。通过盆栽试验研究了杂卤石对玉米生长及养分吸收的影响。各杂卤石处理分别较空白对照增产31. 54%～63. 14%,千粒重分别提高23. 80%～47. 15%,且差异均达显著水平。杂卤石处理的玉米产量分别较氯化钾、硫酸钾及硫酸钾镁处理提高22. 17%～29. 51%,千粒重分别提高7. 67%～12. 92%,差异均达显著水平。杂卤石能改善玉米对钾的吸收,各杂卤石处理玉米植株钾含量分别较空白对照增加21. 79%～93. 50%。适量施用杂卤石能促进玉米对钙的吸收,杂卤石用量为100 kg/hm~2的处理玉米植株钙含量较空白对照增加52. 7%,且杂卤石处理的玉米植株钙含量较3种传统钾肥处理提高了30. 59%～50. 37%。杂卤石能促进玉米对硫的吸收,各杂卤石处理玉米植株硫含量分别较空白对照增加了4. 43%～52. 22%。杂卤石用量与玉米植株钾、钙、硫含量及玉米产量均呈显著正相关关系,同时在杂卤石处理中玉米植株钾含量及钙含量与玉米产量均呈显著正相关关系。杂卤石能够提高玉米产量,促进玉米对钾及钙的吸收。     

The effects on corn and on a rhodic paleudult soil of 17 annual Cu and Zn sulfate additions

A long-term field experiment was established in 1967 and continued through 1983 to evaluate the response of corn (Zea mays L.) and the loading capacity of a Davidson clay loam soil (clayey, kaolinitic, thermic Rhodic Paleudult) to yearly additions of Cu and Zn sulfates. By 1983, the 17 annual additions of Cu and Zn resulted in cumulative totals up to 280 kg Cu and 560 kg Zn ha^?1. These Cu and Zn additions, either alone or together, did not cause any grain or stalk yield decreases. The DTPA extractant separated most of the soil treatment levels for both Cu and Zn. The sevenfold increase in DTPA extractable Cu and eighteenfold increase in DTPA extractable Zn followed linear relationships to treatment levels. Copper concentrations in the blades and grain were not related to soil additions of Cu or Zn. However, Zn concentrations in blades and grain were directly related to each other, to soil Zn treatment levels and to DTPA Zn. Increasing blade Zn concentrations were accompanied by decreasing blade Mn concentrations.     

Applications of fertilizer cations affect cadmium and zinc concentrations in soil solutions and uptake by plants

A pot experiment was conducted to study changes over time of Cd and Zn in soil solution and in plants. Radish was grown in a soil which had been contaminated with heavy metals prior to 1961. Constant amounts of a fertilizer solution (NH₄NO₃, KNO₃) were added daily. Soil solution was obtained at intervals by displacement with water. The cumulative additions of small amounts of fertilizers were made equal to the plants' requirements at the final harvest but were found to exceed them during most of the experiment. Excess fertilizers caused substantial increases of major (K, Ca, Mg) and heavy-metal (Cd, Zn) ions in soil solutions and a decrease in soil pH, probably due to ion-exchange mechanisms and the dissolution of carbonates. Uptake of Cd and Zn into leaves was correlated with the mass flow of Cd (adjusted r²= 0.798) and Zn (adjusted r²= 0.859). Uptake of K, Ca and Mg by the plants was independent of their concentrations in solution. It is concluded that, in order to study effects of plants on heavy-metal availability and obtain soil solution that has not been altered by fertilizer ions, nutrients must be added according to the needs and growth of the plants. This could be achieved by linking fertilizer additions to the rate of transpiration, as nutrient uptake and transpiration were closely correlated in this experiment.     

Lanthanum uptake from soil and nutrient solution and its effects on plant growth

In view of restrictions in the application of antibiotics in animal production, Lanthanum (La) is intended to be introduced as a new growth promoter for pigs. Because most of the supplied La is subsequently excreted, it will be found in organic fertilizers which are applied to agricultural land. Thus, we examined the effect of lanthanum on the growth and La contents of plants in nutrient solution and in soils as well as its extractability from different soils. In nutrient solutions with concentrations of available La of up to 20 μmol L^–1, shoot growth of bush bean was markedly reduced by up to 60% of the control at 20 μM La. By contrast, growth was not affected in maize. Lanthanum was mainly accumulated in the roots, but maize shoot contained considerable amounts of La as well. In contrast to nutrient solution, shoot growth of bush bean and spinach in soils supplemented with La up to 360 μmol kg^–1 (50 mg kg^–1) was not decreased. In contrast to spinach, bush bean shoots showed an increased La content at the highest La level. Extractability of La with 0.1 mol L^–1 acetic acid from 12 different soils previously spiked with La was related mainly to soil pH, CEC, and C_org. We therefore conclude that except of strongly acidic conditions, the application of La‐containing organic fertilizers does not represent a risk for plant growth for the next over 100 years, provided that the recommended doses of feed supplementation is not increased.     

Sewage sludge incinerator ash effects on soil chemical properties and growth of lettuce and corn

Abstract

Incineration reduces sewage sludge volume, but management of the resulting ash is an important environmental concern. A laboratory incubation study and greenhouse pot experiments with lettuce (Lactuca sativa L.) and corn (Zea mays L.) were conducted to examine the potential for recycling elements in sewage sludge incinerator ash in agricultural systems. Ash rates in both the laboratory and greenhouse were 0, 0.95, 3.8, 15.2, and 61.0 g/kg soil (Typic Hapludoll). Ash was also compared to equivalent rates of citrate soluble P from superphosphate fertilizer in a soil‐less growth medium. During soil: ash incubation, Olsen P and DTPA extractable copper (Cu), zinc (Zn), cadmium (Cd), and lead (Pb) increased with incubation time at the higher ash rates. Release rates diminished rapidly, however, and the limited release of these elements after 280 days was associated with decreasing pH. In the greenhouse, ash amendment increased extractable soil P, plant tissue P, and the growth of lettuce and corn. Ash was a less effective P source than superphosphate fertilizer in the soil‐less growth medium and Olsen P levels were more consistent with these differences than Bray P. Ash increased extractable soil levels and plant tissue concentrations of calcium (Ca), magnesium (Mg), sodium (Na), Cu, and Zn, but extractable soil manganese (Mn) and plant tissue Mn decreased. Ash increased soil pH and extractable SO₄‐S. DTPA extractable Cd and Pb increased, but chromium (Cr) and nickel (Ni) decreased. Lettuce accumulated higher amounts of these trace metals than corn, but tissue concentrations were at control levels or below detection limits in both crops.     

氮钾水互作对玉米苗期植株生长及钾素吸收的影响

采用盆栽试验方法探讨了氮钾水互作对玉米苗期植株生长及养分吸收的影响。结果表明,水分适宜能明显增加玉米植株株高和干物重,水分适宜条件下玉米株高和干物重较水分亏缺条件的分别增加7.8%和13.8%。增施氮肥能显著增加玉米植株株高和干物重,水分适宜条件下中氮水平的玉米株高和干物重分别较低氮水平的增加10.4%和8.7%,而水分亏缺条件下株高和干物重均随施氮水平的增加而明显增加;水分亏缺条件下,中高量施钾能显著增加玉米植株干物重。水分适宜条件下增施氮肥能明显促进玉米对钾素的吸收,在水分适宜和亏缺条件下,不同氮水平的玉米钾素吸收均随施钾水平的增加而显著增加。     

土壤添加不同颗粒组成沸石粉对玉米生长及养分吸收的影响

采用土柱试验,研究不同颗粒组成的沸石粉添加到0~20 cm砂壤土耕层对玉米生长、养分累积的影响,为改良沙地提供理论依据。本研究共设8个处理:CK0:不施肥+0 g沸石粉体(简称粉体);CK:施肥+0 g粉体;A:施肥+8 g粉体a;B:施肥+8 g粉体b;C:施肥+8 g粉体c;D:施肥+8 g粉体d;E:施肥+8 g粉体e;F:施肥+8 g粉体f。结果表明,处理A、B、C、D、E、F与CK之间的玉米株高均不存在差异;但其生物量均高于CK,粉体颗粒构成中0.002 mm的含量最高的两个处理E、F达显著水平,分别比CK高71.36%和63.69%。结果还表明,生物量与不同粉体颗粒5个粒级分布的百分比x1、x2、x3、x4、x5即0.05~0.25 mm、0.02~0.05 mm、0.01~0.02 mm、0.002~0.01 mm、0.002 mm百分率之间存在多元回归方程Y=3.69-0.050 6x1+0.082 5x2-0.093 4 x3-0.009 44 x4+0.064 86 x5,表明了玉米生长与颗粒组成之间的密切关系;方程系数表明生物量与细小颗粒含量呈极强的正相关,而与粗颗粒含量呈负相关。与CK处理相比,加粉体处理A、B、C、D、E、F均促进了氮和钾的吸收,但只有处理F对氮的吸收以及E和F处理对钾的吸收达显著水平。显著促进吸收的氮量达74.52%、钾量分别达63.39%和63.62%,而对磷没有显著促进作用。由此可以推论,在此土壤条件下,只有沸石粉体粘粒级颗粒含量高于39%时才显著促进玉米生长发育以及增加植株对氮、钾的吸收和利用。     

Earthworm-mediated maternal effects on seed germination and seedling growth in three annual plants

Many ecological studies have pointed out maternal effects in plants and shown that plant maternal environment influences germination of their seed and subsequent seedling growth. However, few have tested for maternal effects induced by soil macroorganisms. We tested whether two earthworm species (Aporrectodea caliginosa and Lumbricus terrestris) trigger such maternal effects on seed germination and seedling growth of three plant species (Veronica persica, Poa annua and Cerastium glomeratum). Our results show that, through maternal effects, A. caliginosa enhanced seed germination (V. persica and P. annua) and seedling growth (C. glomeratum and P. annua) while L. terrestris reduced seed germination only in V. persica. In some cases, the increase in germination rates of seeds produced in the presence of earthworms was associated with a reduction of nitrogen content in seeds. These results show that earthworms induce maternal effects in plants and that the size and direction of these effects depend on the combination of plant and earthworm species.     

Effects of zinc complexes on the distribution of zinc in calcareous soil and zinc uptake by maize

The movement and availability of Zn from six organic Zn sources in a Typic Xerorthent (calcareous) soil were compared by incubation, column assay, and in a greenhouse study with maize (Zea mays L.). Zinc soil behavior was studied by sequential, diethylenetriaminepentaacetate, and Mehlich-3 extractions. In the incubation experiment, the differences in Zn concentration observed in the water soluble plus exchangeable fraction strongly correlated with Zn uptake by plants in the greenhouse experiment. Zinc applied to the surface of soil columns scarcely moved into deeper layers except for Zn-ethylenediaminetetraacetate (EDTA) that showed the greatest distribution of labile Zn throughout the soil and the highest proportion of leaching of the applied Zn. In the upper part of the column, changes in the chemical forms of all treatments occurred and an increase in organically complexed and amorphous Fe oxide-bound fractions was detected. However, the water soluble plus exchangeable fraction was not detected. The same results were obtained at the end of the greenhouse experiment. Significant increases were found in plant dry matter yield and Zn concentration as compared with the control treatment without Zn addition. Increasing Zn rate in the soil increased dry matter yield in all cases but Zn concentration in the plant increased only with Zn-EDTA and Zn-ethylenediaminedi-o-hydroxyphenyl-acetate (EDDHA) fertilizers. Higher Zn concentration in plants (50.9 mg kg(-)(1)) occurred when 20 mg Zn kg(-)(1) was added to the soil as Zn-EDTA. The relative effectiveness of the different Zn carriers in increasing Zn uptake was in the order: Zn-EDTA > Zn-EDDHA > Zn-heptagluconate >/= Zn-phenolate approximately Zn-polyflavonoid approximately Zn-lignosulfonate.     

Fitting plants to soil through mycorrhizal fungi: Mycorrhiza effects on plant growth and soil organic matter

Summary Vesicular-arbuscular mycorrhizal (VAM) fungi affect diverse aspects of plant form and function. Since mycorrhiza-mediated changes in host-plant responses to root colonization by different VAM fungi vary widely, it is important to assess each endophyte for each specific effect it can elicit from its host as part of the screening process for effectiveness. Three species of VAM fungi and a mixture of species were compared with non-VAM controls for their effects on soil organic matter contents and on nutrition and morphology in two varieties (native and hybrid) of corn (Zea mays L.) and one of sunflower (Helianthus annuus L.) in P-sufficient and N-deficient soil in pot cultures. Differences in soil organic matter due to the fungal applications were highly significant with all host plants. Native corn responded more to VAM colonization than the hybrid did; differences in treatments were significant in leaf area, plant biomass, and root: shoot ratio in the former, but not in the latter. Responses in the sunflower were similar to those in the native corn. Significant VAM treatment-related differences in shoot N and P contents were not reflected in shoot biomass, which was invariant. Correlations between plant or soil parameters and the intensity of VAM colonization were found only in soil organic matter with the native corn, in specific leaf area in the hybrid corn, and in plant biomass in the sunflower. The presence of the different endophytes and not the intensity of colonization apparently elicited different host responses.     

添加物对镉、锌、铅污染土壤上小白菜的生长和养分吸收的影响

A pot experiment was carried out to study the effects of two amendments, lime and calcium magnesium phosphate, on the growth and Cd,Pd,Zn,Cu,Mn,Fe,N,P and K uptake of pakchoi (Brassica chinensis) in a Cd,Pb and Zn polluted acid soil in the southern part of China. The growth of pakchoi was apparently improved by lime and calcium magnesium phosphate application, the uptake of Cd,Pb,Cu and Zn by pakchoi was significantly depressed and the symptom caused by heavy metals pollution was eliminated. Meanwhile, the absorption of N,K and Mn was also inhibited by these amendments. Soil pH was the main factor controlling the uptake of the heavy metals by pakchoi. This suggests that lime and calcium magnesium phosphate could be used as effective amendments for eliminating the toxicity of heavy metals to the vegetable and inhibiting their absorption by the crop.