Showing papers in "Communications in Soil Science and Plant Analysis in 2012"
TL;DR: In this article, a modified dry-ashing (MDA) method was used for the analysis of corn stover pyrolyzed at 300 °C, oak wood at 600°C, and poultry manure with sawdust at 600 °C.
Abstract: Total elemental analyses of biochars presents challenges during digestion because of biochars' high chemical recalcitrance and widely varied composition. Three biochars were chosen with contrasting properties: corn stover pyrolyzed at 300 °C, oak wood at 600 °C, and poultry manure with sawdust at 600 °C. Recovery of phosphorus (P), potassium (K), sulfur (S), calcium (Ca), magnesium (Mg), and zinc (Zn) from poultry manure biochar was 10 to 100 times less with published wet- or dry-digestion methods than when using improved methods. The published dry-digestion method returned significantly (P < 0.05) more sodium (Na), suggesting contamination from borosilicate glassware. A modified dry-ashing (MDA) method was the most precise method, demonstrating a relative standard deviation within 3.7% of the most precise method for recovery of P, K, S, Ca, Mg, and Zn from both corn and oak biochars. The MDA method is comparatively safe and effective for preparing biochar for elemental analysis.
203 citations
TL;DR: Soil organic matter (SOM) is the organic fraction of the soil exclusive of undecayed plant and animal residues as discussed by the authors, which plays a crucial role in maintaining sustainability of cropping systems by improving soil physical (texture, structure, bulk density, and water-holding capacity), chemical (nutrient availability, cation exchange capacity, reduced aluminum toxicity, and allelopathy), and biological (nitrogen mineralization bacteria, dinitrogen fixation, mycorrhizae fungi, and microbial biomass) properties.
Abstract: Soil organic matter (SOM) has long been recognized as an important indicator of soil productivity. The SOM refers to the organic fraction of the soil exclusive of undecayed plant and animal residues. It plays a crucial role in maintaining sustainability of cropping systems by improving soil physical (texture, structure, bulk density, and water-holding capacity), chemical (nutrient availability, cation exchange capacity, reduced aluminum toxicity, and allelopathy), and biological (nitrogen mineralization bacteria, dinitrogen fixation, mycorrhizae fungi, and microbial biomass) properties. The preservation of SOM is crucial to ensure long-term sustainability of agricultural ecosystems. Improvement/preservation of soil organic matter can be achieved by adopting appropriate soil and crop management practices. These practices include conservation tillage, crop rotation, use of organic manures, increasing cropping intensity, use of adequate rate of chemical fertilizers, incorporation of crop residues, liming aci...
160 citations
TL;DR: In this article, the influence of various salinity levels [1 (control), 9 (medium), 17 (high), and 27 dS m−1 (strong)] on nitrogen transformations in soil fertilized with urea and ammonium sulfate was investigated.
Abstract: Laboratory experiments were carried out to study the influence of various salinity levels [1 (control), 9 (medium), 17 (high), and 27 dS m–1(strong)] on nitrogen (N) transformations in soil fertilized with urea and ammonium sulfate. Generally, soil salinization affected the normal pathway of N transformations. The results showed that salinity (medium to high) inhibited the second step of nitrification, causing nitrite (NO2 −) accumulation in soil. The inhibition was more severe in cases of high level of salinity. The greatest salinity level caused inhibition of even the first step of nitrification, leaving more ammonium (NH4)-N accumulation in soil. Severity in nitrification inhibition was observed with increase in salinity and rate of N application, which declined with time. Ammonium accumulation with increased salinity caused N losses in the form of ammonia (NH3) volatilization. After 14 days, the NH3 losses were 1.4-, 2-, and 5-fold greater at 9, 17, and 27 dS m–1 than that of the control (1 dS m–1). A...
69 citations
TL;DR: Co-inoculation of Mesorhizobium sp.
Abstract: We study the effect of plant growth–promoting rhizobacteria (PGPR) along with Mesorhizobium sp. BHURC02 on nodulation, plant growth, yield, and nutrient content of chickpea (Cicer arietinum L.) under field conditions. A similar study has been conducted for nodulation and plant growth of chickpea in pot experiment under glasshouse conditions. The treatment combination of Mesorhizobium sp. BHURC02 and Pseudomonas fluorescens BHUPSB06 statistically significantly increased nodule number plant–1, dry weight of nodule plant–1, and root and shoot dry weights plant–1 over the control under a glasshouse experiment. The maximum significant increase in nodule number, dry matter, and nutrient content were recorded in co-inoculation of Mesorhizobium sp. BHURC02 and P. fluorescens BHUPSB06 followed by co-inoculation of Mesorhizobium sp., Azotobacter chroococcum, and Bacillus megatrium BHUPSB14 over uninoculated control in a 2-year field study. Hence, co-inoculation of Mesorhizobium sp. and P. fluorescens may be effecti...
63 citations
TL;DR: Cattle manure, N fertilizer, and their combination had a highly significant effect on tuber yield and total glycoalkaloid content was affected by the N application only.
Abstract: Management of nutrients, especially nitrogen (N), is one of the most important factors in potato production. Cattle manure and mineral fertilizers are two sources of N that can affect the quality and quantity of potato yield. The effects of the use of cattle manure (5, 10, 15, and 20 ton ha−1), N fertilizer (50, 100, and 150 kg ha−1), and their interaction on tuber yield, chlorophyll content, and glycoalkaloid concentration were evaluated during field experiments in Iran in 2008 with a randomized complete block design with a factorial arrangement of three experimental replications. At the time of flowering, chlorophyll a, b, and total (chlorophyll) were recorded by spectrophotometry. Furthermore, at the end of the growth season, tuber yield was calculated and tuber glycoalkaloids were measured by the colorimetric method for the assessment of quantitative and qualitative characteristics of potato. Chlorophyll a, b, and total content increased linearly and very significantly in response to the application o...
62 citations
TL;DR: In this paper, six factors affecting extraction of soil NO3 −-N and NH4 +-N were investigated in 10 soils sampled from five arable fields in autumn and spring in northwestern China.
Abstract: Extraction of soil nitrate nitrogen (NO3 −-N) and ammonium nitrogen (NH4 +-N) by chemical reagents and their determinations by continuous flow analysis were used to ascertain factors affecting analysis of soil mineral N. In this study, six factors affecting extraction of soil NO3 −-N and NH4 +-N were investigated in 10 soils sampled from five arable fields in autumn and spring in northwestern China, with three replications for each soil sample. The six factors were air drying, sieve size (1, 3, and 5 mm), extracting solution [0.01 mol L−1 calcium chloride (CaCl2), 1 mol L−1 potassium chloride (KCl), and 0.5 mol L−1 potassium sulfate (K2SO4)] and concentration (0.5, 1, and 2 mol L−1 KCl), solution-to-soil ratio (5:1, 10:1, and 20:1), shaking time (30, 60, and 120 min), storage time (2, 4, and 6 weeks), and storage temperature (−18 oC, 4 oC, and 25 oC) of extracted solution. The recovery of soil NO3 −-N and NH4 +-N was also measured to compare the differences of three extracting reagents (CaCl2, KCl, and K2...
53 citations
TL;DR: Leaf total chlorophyll content (LTCC), stomatal conductance (SC), leaf relative water content (LRWC), and membrane leakage (ML) were negatively affected by CS conditions and decreased with reduced temperatures of media, but B and PGPR application alleviate the low-temperature deleterious effect in both species.
Abstract: In 2009 a greenhouse experiment was conducted to determine the effects of boron (B) and plant growth-promoting rhizobacteria (PGPR) treatments, applied either alone or in combination, on yield, plant growth, leaf total chlorophyll content, stomatal conductance, membrane leakage, and leaf relative water content of wheat (Triticum aestivum L cv Bezostiya) and barley (Hordeum vulgare L cv Tokak) plants Results showed that alone or combined B (0, 1, 3, 6, 9 kg ha−1) and PGPR (Bacillus megaterium M3, Bacillus subtilis OSU142, Azospirillum brasilense Sp245, and Raoultella terrigena) treatments positively affected dry weight and physiological parameters searched in both species Statistically significant differences were observed between bacterial inoculation and B fertilizer on root and shoot dry weight under non-cold-stress (NCS) and cold-stress (CS) conditions Leaf total chlorophyll content (LTCC), stomatal conductance (SC), leaf relative water content (LRWC), and membrane leakage (ML) were negatively a
49 citations
TL;DR: In this paper, a laboratory incubation experiment was conducted to determine the dynamics of soil pH and electrical conductivity in a soil to which three animal manures [poultry (PM), cattle (CM), and goat (GM) had been applied.
Abstract: A laboratory incubation experiment was conducted to determine the dynamics of soil pH and electrical conductivity (EC) in a soil to which three animal manures [poultry (PM), cattle (CM), and goat (GM) manures] had been applied. The result of this study showed that the manures differed in qualities. Poultry manure had significantly greater EC and dissolved salts compared with the other manures, whereas the pH of cattle and goat manures are significantly greater than that of PM treatment. The liming effect of the manures was only for about 30 days after manure incorporation, and it varied with manure type and incubation period. There was an increase in EC as days of incubation increased. The potential of manure-induced soil salinization is very high in PM and GM. It was concluded that manure quality and use should be synchronized with consideration of their liming potential and reduced salinization effect.
46 citations
TL;DR: Genetic variability in micronutrient contents in the grain of crops such as rice, corn, wheat, barley, soybean, and dry bean is widely reported in the literature and use of genetic variability among crop species and genotypes within species is an important strategy to achieve biofortification of grain of staple food crops.
Abstract: Micronutrient deficiencies have been reported in food crops worldwide. Several macro- and micronutrients are essential for human health. However, among these elements, the trace elements zinc (Zn), iron (Fe), iodine (I), selenium (Se), and cobalt (Co) are limiting in the diets of much of the world's population. According to United Nations estimates, about 1 billion people, especially woman and children, are suffering from malnutrition of trace elements, especially in Africa, Asia, and South America. Improving bioavailability of these elements in food crops is an important strategy to overcome trace-element deficiencies in food crops and improving human health. Genetic variability in micronutrient contents in the grain of crops such as rice, corn, wheat, barley, soybean, and dry bean is widely reported in the literature. Hence, use of genetic variability among crop species and genotypes within species is an important strategy to achieve biofortification of grain of staple food crops. Other practices that c...
45 citations
TL;DR: The E. aerogenes strain was the most effective strain for reducing the negative effects of salinity, and its effects occurred through increasing the potassium (K+)/Na+ ratio and K+-Na+ selectivity in the eggplant shoots.
Abstract: This study was conducted to elucidate the effects of inoculation with plant-growth-promoting rhizobacteria (PGPR) on eggplant growth, yield, and mineral content under salt stress [0, 25, and 50 mM sodium chloride (NaCl)]. The PGPR strains Xanthobacter autotrophicus BM13, Enterobacter aerogenes BM10, and Bacillus brevis FK2 were isolated from the salt-affected maize and kidney bean fields. The increase in salinity decreased the growth and yield and increased the sodium (Na+) uptake of eggplant. However, inoculation with PGPR strains reduced the negative effects at each level of salinity tested. The E. aerogenes strain was capable of promoting eggplant growth and yield when compared to an uninoculated control. The B. brevis was the most effective strain for reducing the negative effects of salinity, and its effects occurred through increasing the potassium (K+)/Na+ ratio and K+-Na+ selectivity in the eggplant shoots. Inoculation of the eggplant seedlings with PGPR could alleviate the negative effects of sal...
38 citations
TL;DR: A field experiment was conducted on an alluvial soil with winter lettuce [Lactuca sativa (L.) cv. Bacio] plants to study, in the second year of testing and in both field and laboratory conditions, the effects of fertilizers on soil physical and mechanical parameters as mentioned in this paper.
Abstract: A field experiment was conducted on an alluvial soil with winter lettuce [Lactuca sativa (L.) cv. Bacio] plants to study, in the second year of testing and in both field and laboratory conditions, the effects of fertilizers—compost by farm residues [(FC, 2.0% nitrogen (N)], mineral (MIN, 21% N), organomineral (OM, 10% N), mycorrhizas inoculum (MYC), wine-production residue [distiller's residue (DR, 3.6% N), anaerobic digestate (AD), and mycorrhizas (ADM)—on soil physical and mechanical parameters. Application of DR plus mycorrhizas improved the available phosphorus (P) and copper (Cu) contents of the surface (0–0.20 m) soil. The soil surface macroporosity increased significantly (>20%) in treatments FC, MYC, and OM, compared to the control. Results of the oedemeter test showed that with a load of 10 daN the compression susceptibility was greater in the compost treatment compared to other fertilizers, whereas with a load of 200 daN this parameter was lower in FC, AD, MYC, and ADM treatments. The least pene...
TL;DR: The results suggest that ANE may contain compound(s) that promote the legume–rhizobia symbiotic relationship and plant signaling and HPLC profiles and a root hair deformation assay suggested that ANe elicits production of compounds similar to the Nod factor, which are normally induced by the plant signaling molecule luteolin.
Abstract: The soil bacterium Sinorhizobium meliloti forms a symbiotic relationship with alfalfa (Medicago sativa) roots, which results in the formation of intracellular root nodules This symbiosis increases nitrogen (N) in the soil; however, to establish such a synergistic relationship, a complex communication system is required between the bacterium and its legume host Rhizobacteria are known to respond to plant root exudates and produce signal molecules known as “Nod” factors Research suggests that the brown seaweed (Ascophyllum nodosum) extract (ANE) stimulates both root nodulation and growth of alfalfa (Khan et al 2011) To elucidate the mechanism of action, the effects of ANE on the early stages of root–rhizobia interactions were examined A nodosum extract (ANE) and its organic fractions were prepared and alfalfa roots were treated After 2 days, the treated roots were inoculated with S meliloti The roots from treated plants were excised and observed for colony-forming units To verify whether ANE elic
TL;DR: In this paper, the dynamics of calcium (Ca2+), magnesium (Mg2+, sodium (Na+), and potassium (K+) release during decomposition of eight plant residues and two manures over 12 weeks of incubation at 25 ○C were investigated under laboratory conditions.
Abstract: The use of organic residues might be appropriate in maintaining long-term nutrient requirements of crops. We investigated under laboratory conditions the dynamics of calcium (Ca2+), magnesium (Mg2+), sodium (Na+), and potassium (K+) release during decomposition of eight plant residues and two manures over 12 weeks of incubation at 25 ○C. During the processes of decomposition, these nutrients were extracted by 0.1 M sulfuric acid (H2SO4). The release rate of nutrients for residues was best estimated by the exponential model. There were differences in the rates at which release took place between residues and nutrients. In general, release patterns of nutrients with time for all residues were similar in shape, and two regions could be distinguished: a first one during the first 4 weeks of incubation, corresponding to faster release of nutrients, and a second for longer incubation times (weeks 5–12), when the release of nutrients was slower. A 71% loss of K+ was found after 1 week for vegetable waste and onl...
TL;DR: Good agreement between measured and predicted yields was observed while calibrating the QUEFTS model, which shows that the model can be used for making site-specific NPK recommendations for cassava in major cassava production regions of India.
Abstract: Conventional fertilizer-management strategy results in decreased fertilizer-use efficiency and unbalanced nitrogen (N)–phosphorus (P)–potassium (K) applications. The quantitative evaluation of fertility of tropical soils (QUEFTS) model was used for determining region-specific balanced NPK uptake requirements and recommendations for a target yield of cassava. Minimum and maximum internal efficiencies of N, P, and K were estimated as 35 and 80 for N, 250 and 750 for P, and 32 and 102 for K (kg tuberous root per kg nutrient removed). Linear increases in tuberous root yield with N, P, and K uptakes of 17.6, 2.2, and 15.6 kg N, P, and K per 1000 kg tuberous root yield were observed. Relationships between soil supply and soil chemical properties and between fertilizer nutrient recovery efficiencies with their rates of application were developed for major cassava-production regions. Good agreement between measured and predicted yields was observed while calibrating the model, which shows that the model can be us...
TL;DR: In this paper, the results of a multinational study to develop useful calibrations associating NIRS spectra with laboratory-measured results for total soil carbon (C), total soil nitrogen (N), δ13C, and δ15N from a single soil site in Mexico subjected to zero-and conventional-tillage regimens with and without crop residues and crop rotations of maize and wheat across 16 years.
Abstract: Advances in laboratory instrumentation and chemometrics provide alternatives to traditional methods of conducting soil chemical analysis. One of these is infrared diffuse reflectance spectroscopy in the near-infrared spectral range (NIRS). Herein we report the results of a multinational study to develop useful calibrations associating NIRS spectra with laboratory-measured results for total soil carbon (C), total soil nitrogen (N), δ13C, and δ15N from a single soil site in Mexico subjected to zero- and conventional-tillage regimens with and without crop residues and crop rotations of maize and wheat across 16 years. Modified partial least squares regression (MPLS) was used to obtain useful NIR predictions for total soil C and N, with ratio performance deviation (RPD) values of 6.8 and 2.6, respectively. Corresponding multiple correlation coefficients (RSQs) for C and N were 0.98 and 0.85, with standard errors of prediction (SEPs) of ±0.45 g C kg–1 and ±0.09g Nkg–1, respectively. The generation of δ15N and ...
TL;DR: Investigation of the effects of biofertilizers on plant production and nutrient uptake in some Cd-contaminated soils revealed that Cd accumulated primarily in the roots and transport to the shoots was rather low; however, there were differences between the two plants species.
Abstract: Application of various alternative nutrient supplies can partly be substituted by chemical fertilizers, resulting in economical use with less environmental strains. Biofertilizers containing living microorganisms promote nutrition uptake, but still there are questions regarding their application under stress conditions. One of the main abiotic factors that can induce stress is contamination of soils with toxic elements. In the course of intensive plant-growth conditions, considerable quantities of basic cations are removed from the soil, resulting in acidification and thereby enhancing the uptake of heavy metals by plants. Cadmium (Cd) toxicity is a major problem affecting crop productivity worldwide. The presence of Cd in the rhizosphere can cause stress responses and alteration in many physiological processes, including nitrogen metabolism, photosynthesis, carbohydrate metabolism, sulfate assimilation, and plant–water interactions. Once in the plant, Cd can enter the food chain, causing public health pr...
TL;DR: The 1992 Australian Laboratory Handbook of Soil and Water Chemical Methods (the handbook) of Rayment and Higginson defines much of the contemporary soil chemical methodology used in Australia for soil fertility and land-resource survey assessments as mentioned in this paper.
Abstract: The 1992 Australian Laboratory Handbook of Soil and Water Chemical Methods (the handbook) of Rayment and Higginson defines much of the contemporary soil chemical methodology used in Australia for soil fertility and land-resource survey assessments. In addition, codes from the handbook identify methodological details in Australian soil databases, while the codes summarize most tests used for certification purposes by the Australasian Soil and Plant Analysis Council (ASPAC) in its interlaboratory soil proficiency testing programs. A worthy, comprehensive replacement was required as the handbook is out of date in places and out of print. This article provides information on the handbook's replacement with a new book by Rayment and Lyons, titled Soil Chemical Methods-Australasia. Method codes and other strengths of the handbook have been retained and many new tests have been added. There are new chapters on acid sulfate soils, total miscellaneous elements, and miscellaneous extractable elements, plus inclusio...
TL;DR: A potato field experiment was conducted for 2 consecutive years to determine the effects of nitrogen (N) and potassium (K) fertilization rates on the yield and quality of potato cv as discussed by the authors.
Abstract: A potato field experiment was conducted for 2 consecutive years to determine the effects of nitrogen (N) and potassium (K) fertilization rates on the yield and quality of potato cv. Spunta cultivated on soil low in N and K. A 3 × 4 complete factorial experiment was used with three rates of nitrogen (330, 495, and 660 kg N ha–1) and four rates of potassium (112, 225, 450, and 675 kg K2Ο ha–1). An additional treatment without fertilization was used as the control. On soils low in N and K, potatoes showed low yield response to K fertilizer. The greatest tuber yields for both years were achieved at 495 kg N ha–1 and 112 kg K2O ha–1 (29.81 t ha–1) and 225 kg ha–1 (27.13 t ha–1), respectively. Differences in mean fresh weight due to treatment application were not significant. Application of 495 kg N ha–1 significantly reduced harvest index (the ratio of tuber dry weight to the total dry weight at harvest) compared to 330 kg N ha–1, but at 660 kg N ha–1 harvest index achieved the greatest significant value. Pota...
TL;DR: In this article, the effects of different levels of cadmium (Cd) on Cd accumulation and their effects on uptake of micronutrients in Indian mustard [Brassica juncea (L.) Czern] were investigated.
Abstract: A pot experiment was conducted in a greenhouse to evaluate the effects of different levels of cadmium (Cd) on Cd accumulation and their effects on uptake of micronutrients in Indian mustard [Brassica juncea (L.) Czern.]. Cadmium accumulation in shoots and interactions among other metals [manganese (Mn), iron (Fe), copper (Cu), and zinc (Zn)] were investigated. Ten levels of Cd ranging from 0 to 200 mg kg–1 soil were tested. The crop was grown for 60 days in a loamy sand soil with adequate basal fertilization of nitrogen (N), phosphorus (P), and potassium (K), and dry-matter yield (DMY) was recorded. The plants were analyzed for total Cd and micronutrients, and the soil was analyzed for diethylenetriaminepentaacetic acid (DTPA)–extractable Cd. Experimental results showed that the DTPA-extractable Cd in the soil increased consistently and significantly with increase in rates of Cd application up to 200 mg Cd kg–1 soil. Significant reduction in the DMY of Indian mustard occurred with application of 5 mg Cd k...
TL;DR: Results of this study showed that leaf area index and crop growth index were significantly affected by bacterial treatments.
Abstract: Plant-growth promoting rhizobacteria (PGPR) play an important role in plant health and soil fertility. The experiment was conducted as factorial experiment with two factors of Azospirillum and Azotobacter. The bacterial strains were Azospirillum lipoferum s-21, A. brasilense DSM 1690, A. lipoferum DSM 1691, Azotobacter chroococcum s-5, and A. chroococcum DSM 2286. The results indicated that growth promotion by PGPR appears from early stages of growth, 45 days after inoculation (DAI). Beneficial effects of bacterial inoculation on ear growth were observed after 75 DAI. Inoculation with PGPR increased dry weights of leaf, stem, and grain and hence total biomass sampled at 90, 105, and 120 (harvest time) DAI. The greatest grain weight was produced by Azospirillum s-21 inoculation. Dual inoculation with Azotobacter s-5 + Azospirillum s-21 significantly increased total dry weight up to 115%. Results of this study showed that leaf area index and crop growth index were significantly affected by bacterial treatments.
TL;DR: In this article, the authors compared total organic carbon (TOC), total nitrogen (TN), and organic C fractions in postlignite mining soils under different development stages of R. pseudoacacia.
Abstract: In temperate regions, cultivation of Robinia pseudoacacia L. has recently received considerable attention because it is a fast-growing species for biomass and bioenergy production, while acting as a potential carbon (C) sink to counterbalance carbon dioxide (CO2) emissions and an alternative to agricultural crops on marginal sites. The objective of our work was to compare total organic carbon (TOC), total nitrogen (TN), and organic C fractions in postlignite mining soils under different development stages of R. pseudoacacia. Soil samples from three different depths (0–3, 3–10 and 10–30 cm) were taken in plantations 2, 3, 4, and 14 years old (R2, R3, R4, and R14, respectively). The TOC and TN contents increased with increasing tree age in all layers (P < 0.01). In the top 30 cm, TOC and TN stocks ranged from 11.7 to 59.8 Mg C ha−1 and from 0.30 to 2.61 Mg N ha−1 at R2 and R14, respectively. The rate of C sequestration was calculated to be 4.0 Mg C ha−1 year−1. Microbial biomass C and N were strongly correl...
TL;DR: The results suggest that solarization should be practiced before planting horticultural crops in areas with a hot climate, probably because of decomposition of plant residues.
Abstract: Studies were conducted at KPK Agricultural University, Peshawar, Pakistan, in June 2008 and 2009 using a randomized complete block design. Plots were covered with transparent polyethylene films for different periods (0, 2, 4, 6, 8, and 10 weeks). The temperature inside the film was about 10 °C greater than the atmospheric temperature. Solarization increased nitrogen (N) and organic-matter levels in both years, probably because of decomposition of plant residues. Increasing the period of solarization decreased weed density and both fresh and dry biomass. The effectiveness of solarization was species specific. In 2008, Cirsium arvense L. was controlled in the solarized soil, whereas Vicia sativa germination was stimulated by solarization. In 2009, suppressed weeds included Sorghum halepense whereas Chenopodium album L., Cyperus rotundus, and Rumex crispus L. were unaffected. Solarization increased yield of cauliflower (Brassica oleracea L.) in both years. These results suggest that solarization should be pr...
TL;DR: In this paper, the authors evaluated the effect of Conilon coffee (Coffea canephora) cultivated under conventional and organic management systems on the chemical and microbiological characteristics of the soil, as compared to an Atlantic forest.
Abstract: The objective of this study was to evaluate the effect of Conilon coffee (Coffea canephora) cultivated under conventional and organic management systems on the chemical and microbiological characteristics of the soil, as compared to an Atlantic forest. Chemical soil properties, microbial biomass carbon (MBC), microbial biomass nitrogen (MBN), microbial activity (MA), and metabolic quotient (qCO2) were determined at depths of 0–10 cm and 10–20 cm in two seasons (summer and winter). Although microbiological attributes varied according to the season and soil depth, MBC provided 54.15% of relative contribution to distinguish the treatments, followed by MBN and MA. Results indicate that the cultivation of coffee under organic management is more sustainable than under conventional system. Carbon from microbial biomass was the most important soil microbiological attribute in the clustering of the different management methods. Atlantic forest soil followed by organic coffee cultivation soil showed the best soil-q...
TL;DR: The authors' data showed that LA, Chl a and b, and chlorophyll SPAD can be used to discriminate between salt-tolerant varieties and salt-sensitive ones and Deir-Ezzor 22 variety differed by showing high salt tolerance relative to Aleppo 118 and Aleppo 33/1 varieties.
Abstract: Five upland cotton varieties (Gossypium hirsutum L.) (Aleppo 118, Aleppo 33/1, Aleppo 90, Raqqa 5, and Deir-Ezzor 22) were evaluated under different salinity indices [0, 50, 100, and 200 mM sodium chloride (NaCl)] for 56 days. During the course of the experiment, plant size (HT), leaf number (LN) and leaf area (LA), chlorophyll SPAD (Soil Plant Analyses Development), chlorophyll (Chl) a and b content, and osmotic potential were measured in both control and salt-stressed plants for all tested varieties. Salt-stress application reduced the HT and LN of all varieties, whereas LA decreased as salinity level increased for all tested varieties comapared to their respective control expect for Deir-Ezzor 22 variety. Our data showed that LA, Chl a and b, and chlorophyll SPAD can be used to discriminate between salt-tolerant varieties and salt-sensitive ones. In this respect, Deir-Ezzor 22 variety differed by showing high salt tolerance relative to Aleppo 118 and Aleppo 33/1 varieties. Therefore, this investigation...
TL;DR: In this article, the effects of water regimes were tested under extreme climatic conditions (summer in Vega del Guadalquivir, Seville) at two sites during the maximum water-demanding season (June-August period of 2003 and 2004), applied by drip irrigation.
Abstract: Salvia officinalis L. is an aromatic and medicinal species that has medicinal and antioxidative properties. Studying the growth, productivity, and nutrient absorption of this plant under different water regimes is necessary to optimize its cropping techniques. Five irrigation regimes (100, 75, 50, 25, and 0% of ET0) were tested in this trial, through two consecutive years, at two sites during the maximum water-demanding season (June–August period of 2003 and 2004), applied by drip irrigation. The effects of water regimes were tested under extreme climatic conditions (summer in Vega del Guadalquivir, Seville). Data were collected on dry-matter production, mineral nutrition, essential oil production, and the concentrations of bioelements in the airborne organs of the plant to determine the influence of water stress on these indexes. Results showed a significant effect of water regime on dry-matter production, essential oil content, and bioelement concentrations of the plant. Reduced irrigation (from 100% to...
TL;DR: In this paper, seven rates of paper mill effluent (viz., 0, 5, 10, 25, 50, 75, and 100) were used for irrigation of V. radiata (mung bean) along with a control (bore well water).
Abstract: Seven rates of paper mill effluent (viz., 0%, 5%, 10%, 25%, 50%, 75%, and 100%) were used for irrigation of V. radiata (mung bean) along with a control (bore well water). The effluent had significant (P 0.05) effects on moisture content, water-holding capacity (WHC), and bulk density (BD) in both the cultivated seasons: rainy (Kharif) and summer (Zaid) season. The agronomical performance of V. radiata was increased from 5% to 50% in the rainy season and 5% to 25% in the summer season as compared to the control. The enrichment factor (Ef) of various heavy metals were ordered for soil as Pb > Cd, Cr > Zn > Cu in rainy season...
TL;DR: In this article, the influence of nitrogen, phosphorus, and potassium fertilizer doses on iron accumulation in leaves and grains of three high-yielding rice cultivars differing in grain Fe concentration was assessed.
Abstract: Influences of nitrogen (N), phosphorus (P), and potassium (K) fertilizer doses were assessed on iron (Fe) accumulation in leaves and grains of three high-yielding rice cultivars differing in grain Fe concentration. Effects of these treatments were also measured on grain yield, leaf area, and plant biomass of the cultivars. Nitrogen, P, and K applications improved plant biomass and grain yield of all cultivars. Among the nutrients, N was most effective in increasing leaf Fe concentration, followed by P and K in all three rice cultivars. Sharbati accumulated the greatest concentration of leaf Fe followed by IR-64 and Lalat. However, greater doses of these nutrients adversely affected grain yield and Fe content of leaf and grain. Application of excess N, P, and K fertilizers may, thus, sometimes results in lowering of grain Fe content in rice. Judicious application of the elements is recommended for prevention of Fe-induced malnutrition.
TL;DR: Results revealed that intercropping of groundnut with cotton did not significantly affect DM and nutrient partitioning in cotton, but residual soil fertility in terms of potassium permanganate (KMnO4) N showed an improvement in contrast to Olsen's P and ammonium acetate–exchangeable K over sole cotton.
Abstract: A better understanding of the fate of nutrients in transgenic cotton (Gossypium hirsutum L.) fields will improve nutrient efficiencies, will optimize crop growth and development, and may help to enhance soil quality. A study was made to evaluate and quantify the effect of cropping system [sole cotton and groundnut (Arachis hypogaea) intercropping with transgenic cotton] and nitrogen (N) management [control (0N), 100% recommended dose of nitrogen (RDN) through urea, substitution of 25% RDN through farmyard manure (FYM), and substitution of 50% RDN through FYM] on dry matter (DM) and nutrient partitioning and accumulation by transgenic cotton and groundnut at New Delhi during 2006–2007. Soil and plant samples were collected and analyzed at 60, 90, and 120 days after sowing and at harvest. Results revealed that intercropping of groundnut with cotton did not significantly affect DM and nutrient partitioning in cotton, but residual soil fertility in terms of potassium permanganate (KMnO4) N showed an improveme...
TL;DR: In this article, the effects of induced soil compaction on growth and yield of two wheat (Triticum aestivum) varieties grown under two different soil textures, sandy loam and sandy clay loam.
Abstract: The continuous use of heavy machinery and vehicular traffic on agricultural land led to an increase in soil compaction, which reduces crop yield and deteriorates the physical conditions of the soil. A pot experiment was conducted under greenhouse conditions to study the effects of induced soil compaction on growth and yield of two wheat (Triticum aestivum) varieties grown under two different soil textures, sandy loam and sandy clay loam. Three compaction levels [C0, C1, and C2 (0, 10 and 20 beatings)], two textural classes (sandy loam and sandy clay loam), and two genotypes of wheat were selected for the experiment. Results indicated that induced soil compaction adversely affected the bulk density (BD) and total porosity of soil in both sandy loam and sandy clay loam soils. Compaction progressively increased soil BD from 1.19 Mg m−3 in the control to 1.27 Mg m−3 in C1 and 1.40 Mg m−3 in C2 in sandy loam soil while the corresponding increase in BD in sandy clay loam was 1.56 Mg m−3 in C1 and 1.73 Mg m−3 in...
TL;DR: In this article, a modified approach for carbon (C) mineralization using a single-cell infrared gas analyzer (IRGA) was evaluated for 21 days, and the results showed that IRGA did not differ from the GC and NaOH results over 21 days.
Abstract: We evaluated a modified approach for carbon (C) mineralization using a single-cell infrared gas analyzer (IRGA). Objectives were to (i) determine if IRGA, gas chromatography (GC), and alkali absorption of carbon dioxide (CO2) in sodium hydroxide (NaOH) have similar results over 21 days; (ii) determine how these methods correlate; (iii) estimate the limit of quantitation (LOQ); (iv) compare throughput times; and (v) estimate the concentrations of CO2 and oxygen (O2) that suppress respiration. IRGA did not differ from the GC and NaOH results over 21 days. Coefficients of determination (R2) for IRGA, GC, and NaOH had values of 0.92 or more. IRGA and GC had the lowest LOQ (115 and 90 ppm CO2), with the greatest LOQ (600 ppm CO2) found with NaOH. IRGA had the fastest sample throughput (150 h–1), followed by 17 and 10 h–1 for GC and NaOH, respectively. Average suppression concentrations were 5.3% for O2 and 10.5% for CO2.