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1.
Decreasing winter pasture productivity in unlimed Ultisols has been associated with increased soil acidity due to fertilizer N application. The susceptibility of cool season grasses to soil acidity and associated infertility factors that result in reduced forage yield are not well understood. This field study was undertaken to evaluate the effects of factorial combinations of limestone and P applications on annual ryegrass (Lolium multiflorum Lam. ‘Marshall') dry matter production and tissue mineral concentrations on a strongly acid (pH 4.7), sandy soil. Limestone was applied to a Lilbert loamy fine sand (loamy, siliceous, thermic, arenic Plinthic Paleudult) at rates of 0, 672, or 3808 kg ha‐1. Phosphorus was applied to split plots at rates of 0, 30, 60, 90, 120, 240, or 480 kg P ha‐1. Over three harvest years, ryegrass yields increased 90 to 750% and 25 to 80% at the highest lime and P rates, respectively. In the second year, yield response to applied P was significantly less at the high lime rate which indicated that liming made soil P more plant available. Lime and applied P increased plant tissue P, Ca, and Mg concentrations. Yield was positively correlated with soil pH, P, Ca, and Mg and negatively related to soil K and Al. Clear relationships between individual soil test levels and leaf mineral concentrations with yield fluctuations could not be established because these variables were inextricably related to the lime and P rates. Nevertheless, excessive soil Al, coupled with inadequate P, Ca, and Mg availability, were indicated as important nutritional factors limiting annual ryegrass growth in unlimed soil.  相似文献   

2.
Abstract

There is evidence that mugwort (Artemisia vulgaris L.) may have potential for use as a livestock forage. This study was undertaken to determine mugwort growth response to lime, P, and Mg, and their effect on elemental concentration of plant material.

Factorial combinations of 0, 5.6, and 11.2 mt lime/ha; 0, 112, and 224 kg P/ha; and 0, 224, and 448 kg Mg/ha were applied to low pH soil in greenhouse pots and planted to mugwort. In the absence of lime and Mg, growth was very poor. Lime was the most effective treatment in promoting mugwort growth. Growth response to Mg was greatest in the absence of lime, and response to P was dependent on lime and/or Mg application. Macronutrient concentrations of mugwort plants were considered adequate for use as forage for non‐lactating beef cows. Concentrations of several of the micronutrients were very high, especially at low lime and Mg. Copper was high at all treatments.  相似文献   

3.
Lime in pelletized form is potentially more convenient for farmers than ground limestone, as it can be applied using conventional fertilizer‐spreading equipment. Pelletized lime is intended to maintain an optimum soil pH when applied annually at a rate of 350 kg lime/ha/yr. Interactions between lime and N fertilizer rate were examined by applying 0, 75, 150, 225 and 300 kg N/ha/yr (as calcium ammonium nitrate) in combination with 0, 175, 350 and 525 kg pelletized dolomitic lime/ha/yr over 3 yr to a permanent grassland sward used for silage production in County Down, Northern Ireland. Equal rates of ground lime, from the same source as the pelletized lime, were applied as a comparison. Effects on soil chemical properties, grass dry matter (DM) yield and herbage nutrient removal were examined. Lime maintained or slightly increased the soil pH, particularly in the top 2.5 cm of the profile, but there was no difference in the performance of pelletized lime compared to ground lime in any of the parameters measured. Lime had no significant effect on grass DM yield or grass quality; however, there was a significant (P < 0.05) reduction in yield at the first cut, particularly in year 2, when the highest lime rate (525 kg lime/ha/yr) was applied in the absence of N fertilizer. The dolomitic nature of the lime (11% Mg) resulted in significant (P < 0.001) increases in soil and herbage magnesium levels, and this could be beneficial for reducing the incidence of grass tetany in grazing animals. The P content of the herbage was also significantly higher in plots receiving lime, which suggests that lime may have enhanced the mineralization of P or stimulated root growth.  相似文献   

4.
Fertilizer application, particularly nitrogen (N), is important in cool‐season grass forage production. Subsurface (knife) placement of N often has resulted in higher forage yield and N uptake of tall fescue (Festuca arundinacea Schreb.) compared to surface‐broadcast fertilization, but further studies were needed to indicate whether soil pH, phosphorus (P), or potassium (K) modifies the response. Experiment I tested responses of forage yield and N and P concentration to N, P, and K amount and placement. Two types of fertilizer placement ‐ broadcast and knife ‐ were used with 13, 112, or 168 kg N; 0 or 19 kg P; and 0 or 37 kg K/ha in a factorial arrangement. Yields increased by 53% as N fertilization went from 13 to 112 kg/ha and by 69% as N increased from 13 to 168 kg N/ha. Forage yield was increased 26% from knife compared to broadcast fertilizer placement. P application increased forage production by 13%, but K application had no effect on yield. Forage N concentrations increased by 25% as N fertilization went from 13 to 112 kg/ha and by 38% as N increased from 13 to 168 kg N/ha. Effects of added P and fertilizer placement on N concentration often resulted in interactions among factors. Forage P generally was increased by added P, with some effects of interactions among N rate, P rate, and placement. In Experiment II, fescue responses to N placement were tested where different soil characteristics had been established by previous lime and fertility treatments. Forage yield, N concentration, and N uptake were highest where 9.36 Mg/ha of lime were applied as compared to the control. Previous fertility treatments had no significant (P<0.05) effect. When N was knifed, forage yield was related positively to available soil P but not to pH or K. Yield and forage N concentration and uptake were increased by 20, 11, and 33%, respectively, as a result of knife versus broadcast N application.  相似文献   

5.
Abstract

Sulfur (S) deficiency has been reported in some upland soils of the southern United States and S application has improved forage quality on the low‐S soils. A field experiment was conducted for three years to determine ryegrass (Lolium multiflorum L.) dry matter yield and forage quality response to S fertilization. Prilled elemental S was applied each year at two rates (0 and 45 kg S/ha) in combinations with three rates of nitrogen (N) (168, 224, and 280 kg/ha). Wet depositions of S in rain were monitored over the seasons. Sulfur fertilization generally did not increase seasonal dry matter yield and plant uptake of S. Nitrogen application generally increased dry matter yield and protein content during the season. Averaged over the three‐year period, however, forage yield and S uptake increased from 7.7 to 10.5 Mg/ha and 13.9 to 18.8 kg/ha, respectively, as N fertilization increased from the lowest to highest treatment rates. Forage dry matter for each harvest ranged from 0.6 to 2.2 Mg/ha, while S, protein, in vitro dry matter digestibility (TVDMD), and N/S ratio tended to decline seasonally from 2.5 to 1.8, 266 to 142, and 795 to 716 g/kg, and 17.8 to 11.9, respectively. Sulfur input from rainfall was small with a three‐year average of 5.8 kg/ha (±0.64 SE). In some locations of the southern United States, S may not be limiting even when applying high rates of N to high‐yielding forages which annually remove large quantities of S. Because of the lack of yield response from S application and low inputs of S from wet deposition, S from sources other than rainfall may have been considerable.  相似文献   

6.
Two experimental late fall-winter-spring grazing studies, each lasting two years, were conducted at the North Florida Research and Education Center (NFREC), Marianna, Florida to evaluate the organic constituents and macromineral concentrations of annual cool season pasture forages grazed by growing beef cattle. Eight 1.32 ha fenced pastures or paddocks were divided into two pasture land preparation/planting methods, four pastures for the sod seeding treatments and four for the prepared seedbed treatments. These pastures were planted with two different forage combinations: rye/oats mix with or without ryegrass for the first two years (Study 1), and oats with ryegrass or ryegrass only for the last two years (Study 2). Each of the four forage/land preparation combination treatments was assigned to two pastures each year, thereby giving two replicates per year. Forage samples were collected at the start of grazing and twice monthly thereafter until the end of grazing season for each year, pooled by month, and were analyzed for calcium (Ca), phosphorus (P), sodium (Na), potassium (K), magnesium (Mg), dry matter (DM) yield, crude protein (CP), and in vitro organic matter digestibility (IVOMD). Blood plasma samples were also collected from the tester cattle during the spring season of year 2 of Study 2 and were analyzed for Ca, P, and Mg. Month differences were observed in forage concentrations of P and K (P < 0.0001), and Mg (P < 0.05) in both studies, Ca (P < 0.01) in Study 1 only, and Na (P < 0.05) only in Study 2. Year affected P, K, and Mg concentrations in Study 1 and Ca, P, and Na concentrations in Study 2. In Study 2, forage type by month interactions on Ca, K, and Mg concentrations were noticed (P < 0.01). Forage Ca was lower (P < 0.05) than the critical level for all months from the oat plus ryegrass pastures, and for early winter months and late spring months from ryegrass only pasture. Forage Na concentrations were consistently low throughout the grazing season and unaffected by forage type or land cultivation methods used in both studies. Low Mg concentrations of both forage types in Study 2 (also with high K concentrations) were indicative of a potential risk of grass tetany (hypomagnesemia) for grazing ruminants. Forage DM yields were highly variable with fluctuations among the experimental months and were found to be highest in the spring months, with decreasing yields towards the end of the grazing season in both studies (P < 0.0001). The CP concentrations were greater than the required levels and both CP and IVOMD decreased gradually by month in both studies (P < 0.0001). Normal blood plasma concentrations of Ca and P obtained were indicative of a good overall status of these minerals in the animal's body. Plasma Mg concentrations were slightly above the critical level for cattle from both forage types. In summary, the macrominerals most likely to be deficient in North Florida during the cool season would be Ca, Na, and Mg. Special attention should be given to supplementation of Mg since forages reflected a marginal deficiency of this mineral and high K concentrations were found.  相似文献   

7.
Abstract

Results from 2 pastoral field lime trials showed that liming reduced exchangeable Mg. This effect increased with increasing rate of lime and with time following lime application, and was greatest in the top 0–50 mm depth. Soil solutions, sampled 2 years after liming, showed that solution Mg increased in increasing rate of lime. This effect was greatest in the top 20 mm of soil.

Lime incubation studies indicated that Mg fixation did occur on some of the soil studied, at pH >6.2. However, this did not account for the size of the observed effects of liming on exchangeable Mg in the field or explain the observed effects of liming at pH <6.2.

It is suggested therefore, that the major mechanism by which liming reduces exchangeable Mg, on these soils, is through displacement of exchangeable Mg into solution by the added Ca in lime, and subsequent leaching.

Results from other field trials suggest that liming will decrease exchangeable Mg if the change in pH‐dependent CEC (?ECEC) per unit change in soil pH is <15 me 100 g‐1.  相似文献   

8.
Abstract

The cost and difficulty of applying lime on hilly pastures or small forage fields makes it appropriate to devote attention to efficiency of lime utilization. This study evaluated effects of calcitic and dolomitic lime on yield and mineral composition of 11 forage species grown on soil with a low base status of 0.46 cmolc as Ca and 0.18 cmolc as Mg kg‐1. Both lime types increased dry matter production, but only Lolium multiflorum responded more positively to dolomitic lime. The low Mg level in the soil was not a major factor limiting yield. Increase in yield was mainly attributed to the increase in pH with the concurrent decrease in Al level and to an increased Ca availability to plants. The species ranked as follows according to the magnitude of yield increase due to calcitic liming: Trifolium fragiferum > Trifolium pratense > Vicia sativa > Vicia villosa > Trifolium repens > Lolium perenne > Lolium multiflorum > Festuca arundinaceae = Lolium (multiflorum x perenne x perenne) > Trifolium subterraneum > Dactylis glomerata. The most responsive, Trifolium fragiferum, did not grow without lime. The least responsive, Dactylis glomerata, showed a yield increase of 36%. A similar ranking was obtained when all species were evaluated for Al tolerance using a 48 hour root elongation bioassay. In both unlimed soil and soil limed with calcitic lime, Mg concentrations of all species were relatively low. Although they were generally not low enough to have an effect on yield, they barely met the Mg nutritional requirement of cattle. By adding dolomitic lime, Mg content increased in grasses an average of 3.7 fold and in legumes by 2.4 fold. Grasses were similar in Ca, Mg, and K concentrations within a soil treatment. Legumes showed a greater range with the two vetches having the lowest Ca and Mg concentrations and red clover the highest.  相似文献   

9.
Carbonatite rock powder, originating from the Lillebukt Alkaline Complex at Stjernøy in northern Norway, can potentially be used as a slow‐releasing lime and potassium (K) and magnesium (Mg) fertilizer due to a high concentration of the easily weathered minerals calcite (42%) and biotite (30%). However, the enrichment of barium (Ba) and strontium (Sr) may cause an undesired uptake to plants when carbonatite is applied to agroecosystems. A pot experiment was designed to investigate the liming and fertilization effects of carbonatite and the potential mobilization of Ba and Sr compared to a dolomite lime commonly used in Norwegian agriculture. These liming agents were mixed with a sandy soil applied to different amounts of peat, and the uptake of Ba, Sr, calcium (Ca), Mg, and K by Festuca arundinácea Schreb. Kora (tall fescue) and Trifolium repens L. Milkanova (white clover) was evaluated. The liming agents were generally incapable of buffering the acidifying effect from increased applications of peat, while the plant dry mass was unaffected. Compared to pots given dolomite and soluble K, the availability of K from carbonatite to plants was equally high or higher, and no difference in the K:(Ca + Mg) ratio in plants was observed. Carbonatite was a significant source to plant Ba and Sr, and the uptake seemed to follow the Ca uptake. Addition of peat amplified the uptake of Ba, Sr, Ca, Mg, and K to plants, probably an effect of organic acid‐induced weathering of carbonatite. White clover took up Ba, Sr, and Ca more effectively than tall fescue, but the Ba and Sr concentrations in plants were relatively moderate compared to concentrations reported from field investigations.  相似文献   

10.
In a ten‐year study of potassium (K) and lime application to a Kalmia sandy loam (fine‐loamy, siliceous, thermic Typic Hapludult), a soil high in nonexchangeable K, corn (Zea mays L.) and soybean [Glycine max (L.) Herr.] have not responded to applied K. The objectives of this study were to determine if a high K‐requiring crop such as tomato (Lycocersicon esculentum Mill. cv. Redpak) would respond to KCl fertilizer rate or lime type (dolomitic, calcitic, and mixed) and rate on such a soil. Potassium was applied at 0, 56, and 112 kg K/ha every year for ten years. Lime was applied at 0, 2, and 9 Mg/ha in calcitic, mixed, and dolomitic forms twice in ten years (1970 and 1973). In 1980, the tenth year of the study, tomato fruit was harvested by hand once‐over to simulate machine harvest and divided into four maturity groups by color. Soil pH was higher with dolomitic than calcitic lime. Soil K saturation was not influenced by lime rate or type. Fruit yield and leaf phosphorus (P), calcium (Ca), and magnesium (Mg) concentrations increased with increasing lime rates. Leaf K, manganese (Mn), iron (Fe), boron (B), copper (Cu), zinc (Zn), barium (Ba), strontium (Sr), and aluminum (Al) concentrations decreased with increasing lime rate. Leaf Mn, Ba, and Sr concentrations were lower with dolomitic than with calcitic lime. Lime type had no effect on tomato yield. Wide ranges in basic cation saturation ratios had little effect on yield. Soil K saturation and leaf K, Zn, and Ba concentrations increased with increasing K rate. Soil Ca and leaf Ca, Mg, and Al concentrations decreased with increasing K rate. Applied K had no effect on total yield but onceover marketable yield increased linearly with increasing K rate. Marketable yield increased 14% with an increase in K rate from 0 to 56 kg/ha. Thus, fruit maturity was apparently hastened by K fertilization.  相似文献   

11.
Abstract

Lime‐stabilized sludge (LSS) from dairy processing waste‐water treatment plants is a desirable product for land application. The material contains lime, which neutralizes soil acidity, and P, which is useful as a plant nutrient. The fineness of the lime and the solubility of P make LSS especially desirable in establishing forage legumes. This greenhouse study had two objectives: to determine a reasonable quantity of LSS for establishing forage legumes such as alfalfa (Medicago sativa L.) and red clover (Trifolium pratense L.) and to prevent adverse effects on seedlings. Sludge was applied at 0, 2.5, 5.0, 7.5 g kg‐1 to an acid, low P soil in pots, and alfalfa and red clover seeds were sown. All treatments received 123 μg g‐1 potassium as KCl. A completely randomized design with four replications was used. Each species was handled as a separate study. Dry matter production was measured at one‐tenth bloom stage. Plant samples were analyzed for P, K, Ca, and Mg content. Soil samples taken at the end of the study were analyzed for pH, organic matter, Bray P, K, Ca, Mg, exchangeable Al, EC, and CEC. The higher quantities of LSS (7.5 g kg‐1 for alfalfa and 5.0 g kg‐1 for red clover) had negative effects on seedling germination and establishment. Lime‐stabilized sludge resulted in an increase in total nutrient uptake of Ca, Mg, K, and P up to 5.0 and 2.5 g kg‐1 in alfalfa and red clover, respectively. In both species significant dry matter yield increases were obtained with LSS up to 5.0 g kg‐1; however, 7.5 g kg‐1 caused a reduction in dry matter yield. Based on these results, applications of LSS at 5.0 for alfalfa and 2.5 g kg‐1 for red clover had positive effects in seedling establishment, nutrient uptake, and dry matter production. Lime‐stabilized sludge application resulted in significant increases in soil pH, available P, Ca, Mg, EC, and CEC; decreases were seen in neutralizable acidity and exchangeable Al levels in soil. This study indicates that LSS is appropriate for the acidic, low P soils of Southern Missouri for alfalfa and red clover establishment and production, if applied in appropriate quantities.  相似文献   

12.
Lime and phosphorus (P) applications are common agricultural management practices. Our aim was to quantify the effects of long-term application practices on root growth and abundance of arbuscular mycorrhizal fungi (AMF) under field conditions. We assessed the effects of lime and P fertilizer applications on barley yield, root growth and AMF abundance in 2016. Treatments were no, low, medium and high liming rate corresponding to application of 0, 4, 8 and 12 Mg lime ha−1 every 5–9 years since 1942 combined with no or yearly application of 15.6 kg P ha−1 since 1944. At harvest, grain yield, root intensity (core-break) and AMF abundance at different soil depths were estimated. Root development was monitored during early growth with minirhizotrons in treatments receiving low, medium and high liming rates and P fertilization. A quadratic model relating grain yield to liming rate estimated yields to peak at 6.4 Mg lime ha−1 with yields of 4.2 and 3.2 Mg grain ha−1 with and without P fertilization, respectively. Low and medium liming rates resulted in greater AMF abundance, especially in the no P treatments. During early growth in P-fertilized treatments, 77% and 65% more roots developed in the soil profile when treated with medium and high liming rate, respectively, compared to low liming rate. We conclude that long-term application of lime in soils receiving yearly P fertilization improved conditions for root growth in soil layers below 30 cm, but at the high liming rate, this did not translate into higher yield.  相似文献   

13.
Tomato plants were grown for 2 years at 4 different rates of Mg fertilization on a Princeton loamy sand at pH 4.8 with 29 kg exchangeable Mg/ha. Calcareous limestone was used to provide a pH treatment in the second year. Magnesium deficiency symptoms were observed on plants grown on plots having ≤ 38 kg/ha NH4OAC‐extractable Mg. Application of 56 kg Mg/ha corrected Mg deficiency and produced a significant increase in yield. Application of calcitic limestone also produced significant yield increases, but did not affect the development of Mg deficiency symptoms. Tomato yield was increased 27.9% by Mg application and 17.7% by lime application. Highest tomato yield was obtained with application of 112 kg Mg/ha. Symptoms of Mg deficiency were observed when the Mg concentration in recently mature leaf tissue was in the 0.30 to 0.32% range. Magnesium concentration in leaf tissue increased linearly with increasing Mg rate. Leaf Mg concentration at various growth stages of the tomato plant was variable depending on Mg treatment. Magnesium fertilization rate bad little effect on Ca or K leaf concentrations. Application of Calcltic limestone increased leaf tissue Ca and reduced leaf tissue Mg and Mn concentrations.  相似文献   

14.
施石灰石粉后红壤化学性质的变化   总被引：23，自引：0，他引：23       下载免费PDF全文
孟赐福  傅庆林 《土壤学报》1995,32(3):300-307
红壤施用石灰１０年的田间试验和盆栽试验的结果表明施用石灰能降低土壤酸度，增加土壤中效换性Ｃａ和Ｍｇ含量，从而导致作物产量的提高；底土酸度的降低随时间的推移和石灰用量的增大而增强，每倾施用３．２５－１５．０吨石灰石粉的降酸和增产效应至少可维持１０年以上。  相似文献   

15.
Abstract

Pearl millet and annual ryegrass were continually doubled‐cropped on Olivier silt loam soil for seven years at six levels of N, applied as ammonium nitrate in three applications to millet and in two applications to ryegrass. Forage yields increased as N application rates increased. During seven years at the 0 and 448 kg/ha N rate, millet produced 35% and 95%, respectively, as much yield as it produced at the 800 kg/ha N rate, while comparable values for ryegrass were 19% and 83%. At 448 kg/ha of N the two grasses produced a combined yield of over 20 Mg/ha of dry forage per year. Ryegrass yields following millet were consistently lower than yields previously obtained at this site.

Nitrogen applications consistently increased concentrations of N, Ca, and Mg in both forage grasses, while effects on P and K were variable and S concentrations were unaffected. The amounts of all nutrients removed in the forages were increased as yields increased with N application rates. Nitrate‐N levels considered to be toxic to ruminant animals occurred only where N applications exceeded 170 kg/ha at any one time. In vitro digestibility of each grass was consistently increased by N applications.

The percentage of fertilizer N that was removed in the crops ranged from 66% to 68% for millet and from 35 to 52% for ryegrass as N applications increased up to 448 kg/ha. Residual ammonium and nitrate levels in the top 1.2 m of soil were not increased by N rates of 448 kg/ha or lower. At the 800 kg/ha N‐rate, the apparent N recovery rate decreased and residual ammonium and nitrate levels increased throughout the soil profile.  相似文献   

16.
Abstract

Surface liming will prevent the formation of an ‘acid roof’ on the surface of soil cropped in no‐till corn (Zea mays L.). A study was begun in 1985 to determine the effectiveness of unincorporated liming in raising pH in no‐till soil which had developed significant acidity throughout the upper 15 cm. Lime was applied at 0, 3.36, 6.72 and 10.08 Mg ha‐1. All lime was applied on 26 April 1985 and was not incorporated. The pre‐liming pH at 0‐5 cm below the surface was 4.5; after two months the pH was raised to 5.6, 5.8, and 6.0 by 3.36, 6.72 and 10.08 Mg ha‐1 of lime, respectively. After 19 months soil‐pH was raised to 6.0, 6.4 and 6.6 by liming at 3.36, 6.72 and 10.08 Mg ha‐1 respectively. Soil‐pH below 5 cm was not affected by any rate of lime during the first 19 months after liming. Tissue analysis of corn ear leaves indicated that calcium uptake was increased significantly by lime in 1985, while manganese uptake was significantly reduced. In 1986, increases in calcium were greater than in 1985 and addtional significant reduction in manganese uptake was accompanied by significantly reduced zinc and copper uptake. In both 1985 and 1986, a trend toward lower average corn grain yield in unlimed plots than in limed plots was noted, but the yield increases due to lime were not statistically significant in either year. This study will be continued as a long term investigation of lime penetration into no‐till soil and response of corn to soil‐pH changes.  相似文献   

17.
Effects of watershed liming on the biomass and tissue chemistry of planted Picea rubens Sarg. (red spruce) seedlings were investigated for two growing seasons after two subcatchments in a forested Adirondack, New York (U.S.A.) watershed were limed aerially with 6.89 t ha-1 of calcitic limestone (CaCO3). Picea rubens has been the focus of numerous atmospheric deposition research studies, but less well investigated for responses to amelioration. Picea rubens seedlings were planted in limed and reference subcatchments and harvested the first and second growing season after liming to measure total, foliar, and stem (i.e., branch) biomass, and concentrations of Ca, Mg, K, Al, Na, and P in the annual growth increment of foliage and branches. In the second year after liming, both foliage and stem biomass of seedlings from reference plots were at least 50% greater than seedling biomass from limed plots. Seedlings in limed areas had significantly greater foliar concentrations of Mg and P in the first year after liming, but not in the second year. Foliar Ca was not significantly different in limed than reference seedlings. Foliar Al concentrations were greater in reference than limed seedlings, but still below documented toxicity levels. Stem concentrations of Mg, K, and P in seedlings from limed areas decreased significantly between the first and second growing season after liming, while reference seedling stem concentrations either increased or declined only slightly. Correlations among foliar nutrients and foliar biomass from limed plots were negative and suggest an inverse dilution effect. Foliar Al concentrations were negatively correlated with Ca, Mg, K, and P in seedlings from reference plots, but positively correlated in limed plots. The adverse response of P. rubens seedlings to lime may reflect changes in nutrient availability associated with changes in soil pH.  相似文献   

18.
Productivity of resources on acid soils occupying one fourth of the total area in India is abysmally low. Lime is applied to such soils with the primary objective of increasing the productivity of crops by enhancing the availability of native and applied plant nutrients. Greenhouse pot experiments and laboratory experiments were conducted to evaluate the effects of lime and boron (B) on the availability of nutrients in soils and their uptake by plants. The application of lime enhanced the available nitrogen (N,), phosphorus (P), calcium (Ca), magnesium (Mg), sulfur (S), and zinc (Zn) content in soils, which was reflected in their uptake by sunflower (Helianthus annus). On the contrary, availability of copper (Cu), iron (Fe), and manganese (Mn) in soil was reduced due to liming. Sunflower responded very well in terms of dry matter yield to B application to the extent of 175% and 188% under 1 and 2 mg kg?1 applied levels of B, respectively. Dry matter yield of sunflower was reduced to the tune of 29.2 and 42.7% under 2/3 and 1 lime requirement (LR), respectively, over control. Lime application at 1/3 LR with 2 mg kg?1 of applied B emerged as an optimum combination in acid soils.  相似文献   

19.
Soybean is one of the most important legume crops in the world. Two greenhouse experiments were conducted to determine the influence of liming and gypsum application on yield and yield components of soybean and changes in soil chemical properties of an Oxisol. Lime rates used were 0, 0.71, 1.42, 2.14, 2.85, and 4.28 g kg?1 soil. Gypsum rates applied were 0, 0.28, 0.57, 1.14, 1.71, and 2.28 g kg?1 soil. Lime as well as gypsum significantly increased grain yield in a quadratic fashion. Maximum grain yield was achieved with the application of 1.57 g lime per kg soil, whereas the gypsum requirement for maximum grain yield was 1.43 g per kg of soil. Lime significantly improved soil pH, exchangeable soil calcium (Ca) and magnesium (Mg) contents, base saturation, and effective cation exchange capacity (ECEC). However, lime application significantly decreased total acidity [hydrogen (H) + aluminum (Al)], zinc (Zn), and iron (Fe) contents of the soil. The decrease in these soil properties was associated with increase in soil pH. Gypsum application significantly increased exchangeable soil Ca, base saturation, and ECEC. However, gypsum did not change pH and total acidity (H + Al) significantly. Adequate soil acidity indices established for maximum grain yield with the application of lime were pH 5.5, Ca 1.8 cmolc kg?1, Mg 0.66 cmolc kg?1, base saturation 53%, Ca saturation 35%, and Mg saturation 13%. Soybean plants tolerated acidity (H + Al) up to 2.26 cmolc kg?1 soil. In the case of gypsum, maximum grain yield was obtained at exchangeable Ca content of 2.12 cmolc kg?1, base saturation of 56%, and Ca saturation of 41%.  相似文献   

20.
Liming and phosphorus (P) applications are common practices for improving crop production in acid soils of the tropical as well as temperate regions. Four greenhouse experiments were conducted on an Oxisol (clayey, kaolinitic, isothermic, Typic Haplustox) to evaluate response of liming (0,2, and 4 g/kg) and P application (0, 50, and 175 mg P/kg) in a factorial combination on growth and nutrient uptake by upland rice (Oryza sativa L.), wheat (Triticum aestivum L.), common bean (Phaseolus vulgaris L.), and corn (Zea mays L.). Phosphorus application significantly (P<0.01) increased dry weight of tops of all the four crop species as well as dry weight of roots of wheat and corn. Liming significantly (P<0.01) improved growth of common bean and corn but had significant negative effects on rice growth. Maximum dry weight of tops of rice and wheat was obtained at 175 mg P/kg without lime. Maximum dry weight of tops in common bean was obtained at 4 g lime/kg with 175 mg P/kg of soil. In all the crops, increasing levels of applied P significantly increased nutrient uptake. With some exceptions, increasing levels of lime tend to reduce uptake of P, zinc (Zn), copper (Cu), manganese (Mn), and iron (Fe) and increase the uptake of calcium (Ca) and magnesium (Mg) in all the crop species. Decrease in potassium (K) uptake, due to high lime, is probably due to antagonistic effects of Ca and Mg and reduced micronutrients uptake is probably due to increased soil pH resulting in decreased availability of these elements to plants. Therefore, in these types of acid soils, one should avoid over liming.  相似文献   

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