Mn Fertilizers Research Articles

Comparing Manganese Sources for Spring Wheat Grown on Alkaline Soils

The effectiveness of manganese (Mn) sulfate (28% Mn) and manganese oxide 77.5% Mn) as Mn fertilizers for spring wheat (Triticum aestivumL. cv. Brookton) was compared in a glasshouse experiment using two alkaline soils from south-western Australia. Yield of 56-day-old shoots and Mn content (Mn concentration multiplied by yield) of the shoots was used to compare effectiveness of the sources. Both sources were applied as fine powders at equivalent amounts of Mn and were mixed throughout both soils. For both soils, relative to the Mn sulfate (MnSO4), the Mn oxide (MnO) was about 40% as effective for producing shoot dry matter and about half as effective at increasing the Mn content of shoot dry matter. Critical concentration (mg/kg) for producing 90% of maximum yield was about 11 for youngest emerged blades and 17 for whole shoots.

Optimizing Manganese Fertilization for the Suppression of Take‐All Patch Disease on Creeping Bentgrass

Take‐all patch, caused by Gaeumannomyces graminis (Sacc.) Arx. & D. Olivier var. avenae (E.M. Turner) Dennis, is a destructive disease of creeping bentgrass (Agrostis stolonifera L.). Previous research has shown that Mn fertilization can reduce the severity of take‐all patch, but further research is needed to assess the impact of Mn rate and the time of its application on disease development and on the extended residual impact of Mn fertilization on disease suppression. The objective of the current study was to determine the best rate and time of Mn application for the suppression of foliar symptoms of take‐all patch on creeping bentgrass. On a golf course fairway naturally infested with G graminis var. avenae, Mn (as MnSO4) treatments were applied as single applications in either October or April of 1998, 1999, or 2000 at 0, 2.25, 4.50, 6.75, or 9.00 kg ha−1 of Mn. The severity of take‐all patch was assessed each year during May and June when foliar symptoms were apparent. Throughout the study, compared with untreated turf, Mn effectively reduced disease severity when applied either in April or in October. Moreover, the 2.25 kg ha−1 Mn application rate was generally as effective in suppressing the disease as were higher application rates, except in the third year of the study when higher rates were more effective. Findings also suggest that across time previous applications of Mn fertilizer were less effective in suppressing take‐all patch than were the most recent applications of Mn.

Application of Fertilizer Manganese Doubled Yields of Lentil Grown on Alkaline Soils

The yield increase of 45‐day‐old lentil (Lens culinaris Medik) seedlings to applications of two sources of manganese (Mn) fertilizer was compared in a glasshouse experiment using two alkaline soils from southwestern Australia. The Mn sources were manganese sulfate (24.6% Mn), the usual source of Mn for crops in southwestern Australia, and Manganese oxide (MnO; 77.3% Mn). Both sources were finely powdered, applied at equivalent amounts of Mn and were mixed throughout both soils. The effectiveness of the two Mn fertilizers was compared using yield and Mn content (Mn concentration multiplied by the dried yield) of dried lentil shoots harvested 45 days after sowing. Applications of Mn about doubled shoot yields on both soils. For both soils, relative to the Mn sulfate fertilizer, the Mn oxide was about half as effective for producing dried shoots and about 40% less effective in increasing the Mn content of dried shoots so about twice as much Mn as the oxide was required to produce the same yield or Mn content in shoots as MnSO4·4H2O. The concentration of Mn in youngest mature growth (YMG) and in dried shoots was used to determine critical concentrations of Mn in tissue associated with 90% of the maximum yield. The critical concentration (mg/kg) of Mn was found to be 18 for YMG and about 21 in dried shoots.

Using hydrophilic polymers to improve uptake of manganese fertilizers by soybeans

Manganese deficiency in soybeans (Glycine max (L.) Merr.) is a common problem in many parts of the world. Recent research has demonstrated that the addition of gel-forming hydrophilic polymers with plant nutrients may enhance the availability and effectiveness of some soil-applied nutrients. This greenhouse study was designed to determine if the addition of hydrated cross-linked polyacrylamide polymers could increase plant recovery of commonly used Mn fertilizers by soybeans. Four Mn sources (MnO, MnSO4·4H2O, MnCl2, and MnEDTA) were band applied at two concentrations to a low-Mn soil with and without one of two polymers. Addition of either polymer alone or MnO had no effect on leaf or stem Mn concentration, but when MnSO4·4H2O, MnCl2, or MnEDTA were added with a polymer, leaf Mn accumulation swere increased an average of 89%, compared with those Mn sources applied alone. Plant accumulation of Mn from MnO was no greater than the control treatment and uptake was not increased following the addition of polymer. At the conclusion of the experiment, the polymers were still hydrated and the fertilizer band contained an abundance of roots. The use of a hydrophilic polymer with soluble Mn fertilizers appears to enhance the recovery by plants and may lead to lower Mn application rates or perhaps less frequent applications.

Effect of KCl on bioavailability of manganese

Studies were conducted to determine whether KCl application alone or in combination with Mn fertilizer would increase the bioavailability of indigenous and applied Mn and to study the mechanisms by which KCl could enhance Mn uptake by crops. The effect of rates of application (0, 50, 100 and 300 μg K g−1) of two KCl carriers (fertilizer grade and reagent grade KCl), as well as the effects of various salts (KCl, MnSO4, K2SO4, K2CO3, KCl + MnSO4, and KCl + MnSO4 + KI) on Mn uptake by wheat were examined. The effect of KCl on the solubility of soil Mn and applied Mn and the effect of K2SO4 on solubility of soil Mn were examined in calcareous and noncalcareous soils.The two KCl carriers behaved similarly in affecting Mn uptake by wheat. On the calcareous soil only the highest rate of KCl significantly enhanced Mn uptake, whereas on the slightly acidic soil both 100 and 300 μg K g−1 treatments significantly increased Mn uptake. Different salts differed significantly in affecting Mn uptake by wheat, and their effect was observed in the order KCl > K2SO4 > > K2CO3 in both soils, with Mn uptake with K2CO3 being less than in the control. Application of KCl alone, at the higher rates, was as effective as MnSO4 alone in increasing Mn uptake by wheat. Mn uptake by wheat with dual application of MnSO4 and KCl was greater than with separate applications of MnSO4 or KCl. Addition of KCl to MnSO4 fertilizer bands increased amounts of water-soluble Mn in the fertilizer bands. K2SO4 was almost as effective as KCl in increasing water-soluble Mn in MnSO4 fertilizer bands but only for short periods of time (1–3 d). In contrast, KCl increased Mn solubility in the MnSO4 bands for periods up to 56 d. Key words: KCl fertilizer, KCl-enhanced Mn uptake, Mn availability, Mn solubility

Mehlich‐I soil‐test calibration for watermelon: Cu, Zn, and Mn

Abstract Predictive soil tests were used to detect possible need for Cu, Zn, and Mn fertilizers for the optimum production of watermelons (Citrullus lanatus (Thumb.) Masf.) in north and central Florida. Predictive Mehlich‐I soil testing indicated a possible response to additions of Mn and Cu but not to additions of Zn at three locations: Gainesville, Dunnellon, and Live Oak. Results showed no total marketable yield response to selected Cu, Zn, and Mn treatments at any of the three sites. Yields for the Gainesville, Dunnellon, and Live Oak sites were 41.5, 29.0, and 38.0 Mg/ha, respectively, well above the state average watermelon yield of 19.0 Mg/ha. Tissue analyses at the Gainesville and Live Oak sites showed Cu, Zn, and Mn levels within or above suggested sufficiency ranges. This study indicates that current University of Florida interpretations for the Mehlich‐I extractant can identify sites with adequate extractable Cu, Zn, and Mn levels, thus avoiding unnecessary fertilization. At no time were Univer...

Effects of manganese deficiency on the pattern of tillering and development of barley ( Hordeum vulgare c.v. Galleon)

The effects severe, moderate or slight manganese (Mn) deficiency on tillering and development of Galleon barley were examined in field and growth-cabinet experiments. Manganese deficiency delayed maturity in both field and growth-cabinet experiments. In the field, Mn-deficient plants were still tillering when the plants in plots receiving Mn fertilizer had ceased tillering and their stems were elongating. In growth-cabinet experiments, plants with moderate or severe Mn deficiency did not reach the stem-elongation stage of development, and continued to tiller until they died. The pattern of tillering was altered by Mn deficiency. Moderate deficiency decreased the rate of tiller emergence without affecting the rate of leaf emergence on the main culm. Therefore, at early tillering, deficient plants had fewer tillers. Manganese deficiency extended the period of tillering, and after control plants ceased tillering and their stems began elongating, deficient plants continued to tiller, eventually reaching the number of tillers of the control plants. Moderate and severe Mn deficiency prevented stem elongation and reproduction and plants continued to tiller. Eventually, moderate Mn-deficient plants had produced significantly more tillers than control plants or slightly deficient plants. Severe Mn deficiency resulted in death of plants before any increased tiller production. Manganese status affected apical development. When moderately Mn-deficient plants had one tiller, the main stem apex was at the double-ridge stage, compared with four tillers on the control plants which were at the late double-ridge or triple-mound stage. When the number of tillers of the Mn-deficient plants had increased to that of the control plants, the apex of the main stem was dead (shrivelled and dry) in the deficient plants, while that of the controls was at the awn primordium stage. There was no difference in grain-yield of slightly Mn-deficient and control plants, even though early tillering had been depressed and shoot biomass at maturity was lower in the former. Although moderately Mn-deficient plants produced greater number of tillers than control plants, these tillers did not produce any heads.

Increased manganese content of barley seeds can increase grain yield in manganese-deficient conditions

Manganese (Mn) deficiency which decreases barley (Hordeurn vulgare L.) yields can be difficult to eliminate by fertilizer applications. We hypothesized that higher Mn content of barley seed could decrease the severity of Mn deficiency and thus decrease yield loss due to that deficiency. Galleon barley with different amounts of Mn in the seed (low Mn seed: 0.08-0.26 8g per seed; medium Mn seed: 0.34-0 -62 8g per seed; high Mn seed: 0-74-1.208g per seed) was grown in field, glasshouse and growth cabinet experiments. In two experiments, seeds were soaked in MnS04 and had Mn contents of approximately 50 8g per seed. High Mn seed, either obtained artificially by soaking seed in MnSO4 before sowing, or naturally from the parent plant, increased grain yield of barley grown in Mn-deficient conditions. In both -Mn and +Mn treatments, barley grown from high Mn seed had a greater grain yield than that from low Mn seed. High seed Mn increased root dry weight, Mn content of both roots and shoots, shoot dry weight, number of early tillers, plant survival and number of grains per plant, but had no effect on weight per seed. Maximum grain yield was achieved by sowing seed with a high Mn content and applying Mn fertilizer; neither treatment completely corrected Mn deficiency on its own.

Occurrence and Correction of Manganese Deficiency in Histosol‐Grown Rice

AbstractRice (Oryza sativa L.) production is seldom limited by availability of Mn in mineral soils. Manganese deficiency of seedling rice was suspected, however, in drained Histosols with pH values near or exceeding 7.0 in the Everglades Agricultural Area. Several greenhouse and field studies were conducted to verify the occurrence of Mn deficiency, to document its effect on rice growth, and to explore methods for alleviating the deficiency in Histosols. Manganese deficiency was determined to limit the growth of rice seedlings drill‐planted in several drained Histosols having pH values ranging from 6.9 to 7.7. Approximately 3 wk after seedling emergence, deficiency symptoms were evident as interveinal chlorosis on fully expanded leaves. Affected seedlings were shorter, had fewer leaves, weighed less, and had less root mass and length than unaffected seedlings. Affected seedlings contained <20 mg Mn kg−1 tissue. The deficiency also reduced grain yield in the field. In the greenhouse, several methods were investigated for preventing the deficiency. These included soaking seeds in Mn solutions, foliar application of Mn, flooding, or placing Mn fertilizer with the seed at planting. The latter proved to be the best method for preventing the deficiency. The results of the field studies indicated that application of approximately 15 kg Mn ha−1 as MnSO4 with the seed prevented the deficiency and provided near‐maximum grain yields.

Snap Bean Plant Responses to Zinc Sulfate and Manganese Sulfate Fertilization on Tile-drained Calcareous Glacial Till Soils

Effects of lateral movement of soil from tile lines based on soil and plant analysis, plus the effects of applications of ZnSO4 and MnSO4 on the concentrations of Zn, Mn, and other elements in the leaf blades of snap bean plants (Phaseolu vulgaris, var. humilis cv. Bush Blue Lake-47) and on the yield of snap bean pods at harvest were determined. Snap beans were grown across the tile lines and fertilized with five rates of ZnSO4 and MnSO4 fertilizers applied in a band at planting time. The soil decreased in pH and Ca and Mn content and increased in organic matter and Zn with distance from the tile lines. The leaf blades decreased in concentration of Ca and increased in concentrations of Mg, Zn, and Mn with distance from the tile lines. High rates of Zn and Mn fertilizers were required to obtain medium concentrations of Zn and Mn in plants grown over or near the tile lines. Concentrations of 24 to 30 μg of Zn per gram dry weight and 60 to 90 μg of Mn per gram dry weight in the leaf blades of the snap bean plants were adequate for highest yield of pods. Zinc sulfate at a rate of 0.5 to 0.7 g of Zn/m2 produced the highest yield of pods at a distance of 3 m from the tile lines. Applied together, ZnSO4 and MnSO4 produced a yield response similar to application of only ZnSO4. Twenty years after installation of the tile lines, the effects of the tile lines on soil and leaf analysis and yield of pods of snap beans plants extended 2 to 3 m in each direction from the tile lines, indicating that the soil moved laterally.

Soil pH and Manganese Effects on Manganese Nutrition of Peanut1

AbstractManganese deficiency of peanut (Arachis hypogaea L.) is a common problem on some soils of the Coastal Plain region of the southern USA. Information is limited, however, on the concentration of Mn required in the peanut plant. ‘Florunner’ peanut was grown on a Pelham sand (loamy, siliceous, thermic, Arenic Paleaquult) to determine soil pH and Mn effects on Mn nutrition of peanut. Soil‐applied Mn treatments of 0, 10, 20, and 40 kg ha−1 were compared at pH levels near 5.2, 6.0, and 6.8. Manganese deficiency occurred only on plots with pH levels near 6.8 where yields were increased by applying up to 40 kg Mn ha−1. Critical Mn levels were 13, 15, 15, 15, 13, and 12 mg kg−1 in leaves collected at 7, 9, 11, 13, 15, and 17 weeks after planting, respectively. Pod yields averaged 3.41, 5.40, and 5.73, and 6.37 Mg ha−1 at pH level near 6.8 for 0, 10, 20, and 40 kg Mn ha−1 treatments, respectively. Maintaining a soil pH near 6.0 provided a desirable medium for peanut production without the need for Mn fertilizer.

Low efficiency of manganese fertilization of soybeans on a haplaquept soil

Abstract Manganese deficiency is frequently encountered in soybeans (Glycine Max. L., Merrill) on naturally high pH, fine textured, poorly drained soils (Vertic Haplaquept) in Kentucky. Information is needed for diagnosing deficient fields by soil tests and on the efficiency of Mn fertilizer applied to these soils. At two locations where Mn deficiency had occurred, MnSO4 was applied at annual rates up to 360 and 600 kg of Mn/ha. At site 1, where DTPA extractable Mn averaged 5.9 pg/g on untreated soil with pH of 7.4, seed yields were increased significantly in 1977 and over the three‐year period by Mn fertilization. Yields were unaffected by treatment at site 2, where extractable Mn averaged 5.8 pg/g and pH was 6.3. Concentrations of Mn in trifoliates of plants growing in untreated soil averaged 15–16 pg/g for three of the five site‐years. However, there were apparent seasonal effects of climate on Mn availability in certain years which resulted in Mn levels of 24–29 pg/g in trifoliates of plants growing i...

Methods and Rates of Applied Manganese for Soybeans1

AbstractSoybeans [Glycine max (L.) Merr.] have responded to supplemental Mn fertilizer on high water table soils when limed to soil pH levels near neutrality, but the effect of method and rate of Mn application under these conditions is not well understood. In a 3‐year study (1975–1977) on an Olustee‐Leefield sand (Ultic Haplaquod‐Arenic Plinthaquic Paleudult), four application methods (broadcast preplant, row at planting, sidedress, and broadcast preplant plus foliar spray), at four rates (0, 5.6, 11.2, and 22.4 kg/ha) of Mn were employed to evaluate their effects on yield, leaf blade concentrations, seed Mn levels, and extractable soil Mn levels. A 239% yield increase was obtained in 1977 with 11.2 kg Mn/ha compared to no applied Mn. Yield increases due to applied Mn were not obtained in 1975 and 1976, although visual deficiencies were evident early in the growing season every year. Yield increases were related to seed weight for the various Mn rates. Methods of Mn application did not influence yields in any given year. However, the row at planting application may have produced toxic effects since there were visual toxicity symptoms and trends of decreased yields each year. Leaf tissue sampled at the R‐2 growth stage indicated the Mn level should be greater than 15 ppm for maximum yields with broadcast application and the critical Mn level in the seed is 16 ppm. In this study, correlation and regression analyses indicated the seed Mn levels were better related to yield than leaf blade Mn levels. Double acid extractable soil Ma increased from 1975 through 1977 while DTPA extractable Mn showed a slight decrease. Both methods were well related to applied Mn rates. These data indicate that applied Mn rates influence soybean yields, soil Mn, tissue Mn, and seed Mn concentrations more than methods of Mn application.

Development of a DTPA Soil Test for Zinc, Iron, Manganese, and Copper

AbstractA DTPA soil test was developed to identify near‐neutral and calcareous soils with insufficient available Zn, Fe, Mn, or Cu for maximum yields of crops. The extractant consists of 0.005M DTPA (diethylenetriaminepentaacetic acid), 0.1M triethanolamine, and 0.01M CaCl2, with a pH of 7.3. The soil test consists of shaking 10 g of air‐dry soil with 20 ml of extractant for 2 hours. The leachate is filtered, and Zn, Fe, Mn, and Cu are measured in the filtrate by atomic absorption spectrophotometry.The soil test successfully separated 77 Colorado soils on the basis of crop response to Zn, Fe, and Mn fertilizers. Critical nutrient levels must be determined separately for each crop using standardized procedures for soil preparation, grinding, and extraction. The critical levels for corn using the procedures reported herein were: 0.8 ppm for Zn, 4.5 ppm for Fe, and tentatively 1.0 ppm for Mn, and 0.2 ppm for Cu.Development of the soil test was based, in part, on theoretical considerations. The extractant is buffered at pH 7.30 and contains CaCl2 so that equilibrium with CaCO3 is established at a CO2 level about 10 times that of the atmosphere. Thus, the extractant precludes dissolution of CaCO3 and the release of occluded nutrients which are normally not available to plants. DTPA was selected as the chelating agent because it can effectively extract all four micronutrient metals. Factors such as pH, concentration of chelating agent, time of shaking, and temperature of extraction affect the amount of micronutrients extracted and were adjusted for maximum overall effectiveness.

Correction of Mn Deficiency of Soybeans1

AbstractThe objective of this study was to compare rates of Mn application and methods of Mn application to correct Mn deficiency of soybeans (Glycine max L.) in planting systems where no starter fertilizer is utilized. Field experiments were conducted at three locations in the Coastal Plain region to evaluate broadcast and foliar applications as well as band placement of granular Mn fertilizer in the row with seed. The latter application was accomplished by utilizing a conventional granular insecticid applicator. Soils studied in this investigation included two aquic hapludults and one typic quartzipsamment.Applications of 5.6, 11.2, and 16.8 kg Mn/ha bandplaced in the row with seed produced yield increases of soybeans on both limed and unlimed areas at one location. Soybean yield increases were obtained at this location from broadcast applications of 11.2, 22.4, and 44.8 kg Mn/ha on the unlimed soil, and from the 22.4 and 44.8 kg Mn/ha on the limed soil. A foliar treatment of 2.2 kg Mn/ha also produced grain yield increases. Only the 11.2 and 16.8 kg Mn/ha band‐placed with seed, and the 11.2 kg Mn/ha broadcast treatments on the limed soil gave soybean yield increases at a second location. Drought conditions prevailed at the third site and no soybeans emerged on the 11.2 and 16.8 kg Mn/ha bandplaced with seed treatments.In planting systems where conventional band placement of fertilizer is not practical, band placement of Mn in the row with seed can increase yields on soils supplying insufficient Mn for plant growth. Plant populations can be reduced by band placement of Mn in the row with seed under adverse moisture conditions. Broadcasting high rates of Mn or repeated foliar applications of Mn will also correct Mn deficiency of soybeans.

Effect of Soil and Foliar‐applied Manganese on the Micronutrient Content and Yield of Soybeans1

AbstractManganese deficiency of soybeans (Glycine max (L.) Merr.) will undoubtedly become more prevalent as soybean acreage increases along with strong emphasis on yield maximization. Thus, field experiments were conducted on two soils (Argiaquoll and a Hapludoll) in southern Wisconsin to evaluate sources, rates, and methods of application of Mn fertilizers on soybeans. Two sources, MnSO4 and Mn‐ethylenediaminetetraacetic acid (MnEDTA), were broadcast, row or foliar‐applied at various rates to Mn‐deficient soils and/or soybeans. Micronutrient concentrations, Mn uptake, and various production parameters were measured.All rates and application methods of MnSO4 and foliar applications of Mn‐EDTA were effective in supplying Mn to the plant. Row applications of MnSO4 were somewhat more efficient than broadcast applications. Manganese applied at rates ranging from 5 to 22 kg Mn/ha as MnSO4 with the starter fertilizer in the row at planting time appeared to be most efficient soil treatments in increasing seed yields. The MnEDTA applied in the row reduced plant weight, leaf Mn, and soybean yields slightly. When Zn was not included in the starter fertilizer, leaf Zn and Cu were increased by the soil‐applied MnEDTA treatments. Leaf Fe was not affected by any of the Mn treatments.Foliar applications of Mn were most effective when applied at the early blossom or early pod set stages or in multiple applications at these stages. Single applications of 2.24 and 4.48 kg Mn/ha as MnSO4 or 0.51 kg Mn/ha as MnEDTA caused some burning of the foliage.Combined row and foliar methods of application also appeared to relieve Mn deficiency effectively. Small amounts of MnSO4 applied in the row corrected the Mn deficiency early in the season, whereas foliar applications adequately supplied Mn to the plant later in the growing season. This combination resulted in higher yields than with either row or foliar treatments applied alone.

Effect of N, P and K fertilizers on the availability of native and applied manganese to wheat

SUMMARYThe influence of three rates of each of N, P and K fertilizers on the availability of native and applied Mn to wheat was studied in a field experiment on an alluvial soil of the Indo-Gangetic plain. Increasing dressings of N as ammonium sulphate resulted in consistently higher yields and Mn uptake by the crop. Concentration of Mn in the grain increased with increasing N dressings when native Mn and Mn fertilizer supplied this nutrient but it was unaffected inplants sprayed with Mn. Adding P as superphosphate tended to lower the concentration of Mn in the grain when relying on native or applied Mn but it significantly enhanced the crop yield and total Mn uptake. Applying K as muriate of potash slightly depressed Mn uptake by plants. Potassium had a more pronounced effect in the absence of P fertilizer. The concentration of Mn in thestraw was not significantly affected by N, P and K fertilization.