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11.
Abigail E. Baxter Rory O. Maguire Garnett Whitehurst David Holshouser Mark Reiter 《Communications in Soil Science and Plant Analysis》2019,50(1):65-76
Soybean (Glycine max) commonly experience Mn deficiencies in the coarse-textured soils of Coastal Plain Virginia, especially under high pH conditions. The objective of this study was to investigate the ability of a novel coated fertilizer to provide Mn and B to soybeans in soils where Mn deficiency is common and B deficiency, although far less common than with Mn, is possible. A 60-d greenhouse experiment was conducted with three treatments: control, uncoated KCl, and Mn +B coated KCl applied to Bojac and Dragston sandy loams. Soil and whole plant tissue samples were collected throughout the experiment. Bojac and Dragston soils treated with the coated KCl contained 12.0 mg kg?1 and 15.8 mg kg?1 more Mehlich 1 – Mn, 21.7 mg kg?1 and 23.0 mg kg?1 more Mehlich 3 Mn, and 4.5 mg kg?1 and 4.6 mg kg?1 CaCl2 – Mn than the control and uncoated KCl, respectively. Coated KCl increased above ground tissue Mn by 42.9 mg kg?1 compared to the control and the uncoated KCl treatments in the Bojac soil, while the Dragston soil showed no significant differences in Mn tissue concentration between treatments. Above ground tissue, Mn was much lower in the Dragston soil than the Bojac, probably due to greater organic matter which chelates Mn keeping it less plant available. Boron concentrations did not differ in plant tissue or soil, regardless of the extraction method. Results indicate that the coated KCl product could consistently provide increased Mn concentration in acidic sandy soils despite varying levels of organic matter, but is not effective for B. 相似文献
12.
Assessment of nickel's sufficiency critical levels in cultivated soils,employing commonly used calibration techniques 下载免费PDF全文
Although Ni has been officially recognized as an essential micronutrient for all higher plants since 2004, research on assessing its sufficiency critical levels with different soil tests is missing in the literature. The objective of the study was to determine Ni critical levels in unpolluted cultivated soils utilizing four methods, employing three commonly used calibration techniques. Ten soils with different physical–chemical properties and low Ni content were treated with Ni at rates of 1, 2, 4, and 8 mg kg?1. After equilibration for one month, the soils were analyzed for extractable Ni by four methods, namely DTPA, AB‐DTPA, AAAc‐EDTA, and Mehlich‐3. Response to soil‐applied Ni was assessed by a greenhouse pot experiment, with the untreated and Ni‐treated soils in three replications, using ryegrass (Lolium perenne L.). The aboveground biomass of ryegrass was harvested two months after sowing, dry weight of biomass was measured and relative biomass yield was calculated. Nickel's critical levels were determined employing the: (a) graphical technique of Brown and co‐workers, (b) Mitscherlich–Bray equation, and (c) Cate and Nelson graphical technique. According to the first technique, Ni critical levels were ≈ 2 mg kg?1 for the DTPA and AB‐DTPA methods, and 6.0 and 5.3 mg kg?1 for the AAAc‐EDTA and Mehlich‐3 methods, respectively. Similar levels were obtained by the Mitscherlich–Bray equation. However, the critical levels assessed by the Cate and Nelson technique were lower and ranged from 0.5 to 1.3 mg kg?1 for all four methods. Conclusively, Ni sufficiency critical levels for all four methods are expected to range at levels of a few mg Ni kg?1 of soil. As far as the three calibration techniques are concerned, a distinct boundary between Ni response and non‐response was accomplished by none. However, the fact that 60–74% of the soils were correctly separated into responsive and non‐responsive to added Ni by the graphical technique of Brown and co‐workers suggests that this is the most suitable technique. 相似文献
13.
Oil cultivars of Brassica napus L. were grown to compare the effects of composted municipal waste (CMW) and sheep manure (SM) to field soil (C0). To each soil group, one of three levels of urea nitrogen fertilizer (N) was added. SM grown plants had higher N than those grown in CMW with the Sarigol cultivar having a higher N content than the RGS cultivar. Field soil plants grown in control soil had lowest N levels. Organic amendments increased N content of both cultivars. SM grown plants produced more siliques, a higher seed yield, and greater 100 seed weight compared to those grown in CMW. Control soil plants had the lowest number of siliques, seed yield, and 100 seed weight. CMW-treated plants contained slightly more metals than SM plants. Field soil plants had the lowest metal levels. CMW and SM application had potential to improve the growth and chemical composition without adding urea. 相似文献
14.
Labile soil organic carbon,soil fertility,and crop productivity as influenced by manure and mineral fertilizers in the tropics 总被引:1,自引:0,他引:1
In recent years, organic agriculture has been receiving greater attention because of the various problems like deterioration in soil health and environmental quality under conventional chemical‐intensive agriculture. However, little information is available on the comparative study related to the impact of use of mineral fertilizers and organic manures on the soil quality and productivity. A long‐term field experiment was initiated in 2001 to monitor some of the important soil‐quality parameters and productivity under soybean–wheat crop rotation. The treatments consisted of 0, 30, and 45 kg N ha–1 for soybean and of 0, 120, and 180 kg N ha–1 for wheat. The entire amount of N was supplied to both the crops through urea and farmyard manure (FYM) alone or in combination at 1:1 ratio. Results indicated that Walkley‐and‐Black C (WBC; chromic acid–oxidizable) exhibited a marginal increase under only organic treatments as compared to control treatment (without fertilizers and manure) after completion of five cropping cycles. In case of labile‐C (KMnO4‐oxidizable) content in soil, relatively larger positive changes were recorded under organic, mixed inputs (integrated) and mineral fertilizers as compared to WBC. Maximum improvement in the values of C‐management index (CMI), a measure of soil quality was recorded under organic (348–362), followed by mixed inputs (268–322) and mineral fertilizers (198–199) as compared to the control treatment after completion of five cropping cycles. Similarly there was a substantial increase in KCl‐extractable N; in Olsen‐P; as well as in DTPA‐extractable Zn, Fe, and Mn under organic treatments. Although labile soil C positively contributed to the available N, P, K, Zn, Fe, and Mn contents in soil, it did not show any relationship with the grain yield of wheat. After completion of the sixth cropping cycle, organic treatments produced 23% and 39% lower grain yield of wheat as compared to that under urea‐treated plots. Relatively higher amount of mineral N in soil at critical growth stages and elevated N content in plant under mineral‐fertilizer treatments compared to FYM treatments were responsible for higher yield of wheat under mineral fertilizers. 相似文献
15.
Matthias Westerschulte Carl-Philipp Federolf Dieter Trautz Gabriele Broll Hans-Werner Olfs 《Journal of plant nutrition》2018,41(11):1381-1396
Slurry injection below the maize (Zea mays L.) row may substitute a mineral nitrogen (N) phosphorus (P) starter fertilizer (MSF) and thus reduce nutrient surpluses in regions with intensive livestock husbandry. We investigated the plant P, zinc (Zn), and manganese (Mn) status compared to the current farm practice. In 2014 and 2015 field trials were conducted to evaluate plant nutrient status at different growth stages. Besides an unfertilized control, two slurry injection treatments (±nitrification inhibitor (NI)) were compared to slurry broadcast application plus MSF. In both experiments NI addition significantly increased nutrient concentrations during early growth (6-leaf 2015: +33% P, +25% Zn, +39% Mn). Under P deficiency due to cold weather conditions broadcast application showed higher P uptake until 6-leaf (36–58%), while it was lower at 8- (32%) and 10-leaf (19%) stage compared to slurry injection (+NI). Zn availability was enhanced for slurry injection (+NI) during early growth and Zn and Mn uptakes were higher at harvest. Slurry injection decreased P balances by 10–14 kg P ha?1, while Zn and Mn balances were excessive independent of treatments. Slurry injection (+NI) can substitute a MSF without affecting early growth and enhances the Zn and Mn status. This new fertilizing strategy enables farmers to reduce P surpluses. 相似文献
16.
José Zilton Lopes Santos Bruno Fernando Faria Pereira José Augusto Figueira da Silva Carlos Alberto Franco Tucci Sílvio Vieira da Silva Tainah Manuela Benlolo Barbosa 《Communications in Soil Science and Plant Analysis》2017,48(11):1280-1290
We evaluated the effects of macronutrient and micronutrient omission, and of liming, on Jatropha curcas (JC) in greenhouse study. The experimental design was a factorial combination of 2 liming treatments (nil or 4.5 t. ha?1 of dolomitic lime) x 7 combinations of fertility status, with five replications. The concentrations and uptake of nutrients by JC plants follow the order: nitrogen > potassium > calcium ≥ Magnesium > sulfur > phosphorus > iron > boron > manganese > zinc > copper (N > K > Ca ≥ Mg > S > P > Fe > B > Mn > Zn > Cu), but the growth of JC plants was negatively affected mainly by omission of macronutrients, in the following order: P > N = K = S, on limed soil. Phosphorus is the most critical element for development. JC is responsive to micronutrients only when applied together with macronutrients. Potassium chloride is not recommended as K+ source for JC crop. Lime is recommended to improve growth and nutritional status of JC plants. 相似文献
17.
Ammonium and nitrate are the major forms of nitrogen (N) present in tropical soils. An experiment was conducted to assess the influence of nitrate and ammonium forms (NO3?, NH4+, and mix of NO3? + NH4+), and levels (1.5–12.0 mM) of N on the growth and nutrition of cacao (Theobroma cacao L). Growth parameters were significantly influenced by N forms, and nitrogen supplied as NH4+ proved better for the growth of cacao compared with NO3? form and mixtures of these two forms. Irrespective of the forms of N, levels of N had no significant effect on plant growth parameters. Nutrient efficiency ratios (NERs) (shoot dry matter produced per unit of nutrient uptake) for macronutrients were sulfur>phosphorus>calcium>magnesium>nitrogen>potassium (S>P>Ca>Mg>N>K) and for micronutrients NERs were in the order of copper>boron>zinc>iron>manganese (Cu>B>Zn>Fe>Mn). 相似文献
18.
Rilner Alves Flores Ricardo Gomes da Silva Patrícia Pinheiro da Cunha Virgínia Damin Klaus de Oliveira Abdala Everton Martins Arruda 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2017,67(8):697-704
Foliar fertilization may be a viable strategy to boron supply in irrigated cropping systems with common beans (Phaseolus vulgaris), since it prevent B leaching. The aim of this work was to evaluate the economic viability and physiological parameters of the common beans production in irrigated cropping systems using sources and increasing foliar boron doses. A field experiment was carried out using an experimental block design in a factorial scheme 2?×?5?×?3, with two sources of B (boric acid and borax) and five doses: 0 (control), 2, 4, 6 e 8?kg?ha?1, with three repetitions. Foliar B applications were performed at 40 days after seeds germination, in pre-flowering stage. Physiological process (transpiration, stomatal conductance, CO2 internal concentration, net photosynthesis, and relative chlorophyll index), B level in leaves and grain yield were measured. These data were used to determine the economic viability of B fertilization in common beans. Both boric acid and borax increased B levels in common beans leaves. Borax affected some physiological process reducing stomatal conductance and increasing net photosynthesis. Using borax, the highest net photosynthesis was observed at a rate of 4?kg?ha?1, while the boric acid increased net photosynthesis linearly after increasing B doses application. An enhance of 311?kg?ha?1 in the grain yield was observed using borax related to the control (without B application); however, grain yield decreased linearly after application of increasing B doses, as boric acid. Comparing the economic viability of sources and doses of B, the highest profitability is obtained using borax at a rate of 4?kg?ha?1, which promoting a differential profit of US$534.44 per hectare compared to common beans cropping without B. 相似文献
19.
《Communications in Soil Science and Plant Analysis》2012,43(15-16):2484-2499
Desilication and leaching are processes that accompany plinthilization, leading to nutrient depletion. Soils from 12 profiles in a plinthitic landscape were analyzed for extractable micronutrients [iron (Fe), zinc (Zn), manganese (Mn), and copper (Cu)]. Soils of the landscape from crestal to lower‐slope position contain plinthite in the profile, whereas those of the valley floor are devoid of plinthite. The micronutrients were extracted using diethylenetriaminepentaacetic acid (DTPA) and 0.1 M hydrochloric acid (HCl). The results showed that 0.1 M HCl extracted more of the micronutrients than DTPA. The DTPA‐extractable Fe, Zn, Mn, and Cu in all the soils ranged from 1.15 to 12.44 (mean, 3.69); 0.71 to 2.75 (mean, 1.86); trace 12.44 (mean, 3.35), and trace 3.76 (mean, 0.63) mg kg?1, respectively. The DTPA‐extractable micronutrient contents were generally greater than the critical available level (4.5 mg kg?1 for Fe, 0.8 mg kg?1 for Zn, 1.0 mg kg?1 for Mn, and 0.2 mg kg?1 for Cu). The 0.1 M HCl‐extractable micronutrients in the landscape ranged from 8.00 to 30.40 (mean, 15.19); 0.30 to 6.49 (mean, 1.35); 1.00 to 27.20 (mean, 7.74); and 0.26 to 15.0 (mean, 2.77) mg kg?1 for Fe, Zn, Mn, and Cu, respectively. Both DTPA‐ and 0.1 M HCl‐extractable micronutrients were generally lower in the plinthitic horizons than in the nonplinthitic horizons and higher in the Ap than the subsoil horizons. Correlation analysis showed a significant relationship between DTPA‐Fe and DTPA‐Mn, Cu, and organic carbon (r = 0.913**, 0.411**, and 0.385**). There was a significant and positive relationship between 0.1 M HCl‐extractable Mn and organic carbon (C), total nitrogen (N), and available phosphorus (P) (r = 0.413**, 0.337**, and 0.350**, respectively). 相似文献
20.
《Communications in Soil Science and Plant Analysis》2012,43(6):665-678
The present study was conducted to investigate in sunflower the processes of boron (B) uptake, intracellular compartmentation, and xylem translocation in response to B supply, ranging from deficiency to incipient toxicity, and to short-term changes in B supply. The experiments were conducted with two sunflower genotypes, selected on the basis of their susceptibility to knife-cut disease. It appears that the roots of the susceptible genotype of sunflower were more sensitive to low B contents in the solution media than the shoots. The decrease in root dry weight in high-B treatments could also indicate it was more sensitive to B toxicity. Though root dry weight decreased, the shoot/root dry-weight ratio was smaller in the resistant genotype, suggesting that this genotype would have a substantially larger root volume, capable of supporting the B demand of its shoots. The B contents in the water-insoluble residue (WIR) of roots were similar for all genotypes and treatments. In contrast, the B concentration in WIR of leaves reached values near saturation only when B started to accumulate in the cell sap (CS) of roots to the level as detected in CS of leaves. The critical values of B concentrations in shoot tissues would then be established after the B requirement for cell walls was satisfied and a proper metabolic B content in CS of roots was reached. Uptake efficiency (UE) values less than 1.00, detected as a result of treatments with high concentrations of B in the nutrient solution, suggested the presence of an exclusion mechanism that restricted B accumulation. The high UE value obtained with low-B treatments indicated that mechanisms other than mass flow had played a role in providing the acquired B. 相似文献