Cl Treatments Research Articles

First-principles study of roles of Cu and Cl in polycrystalline CdTe

Cu and Cl treatments are important processes to achieve high efficiency polycrystalline cadmium telluride (CdTe) solar cells, thus it will be beneficial to understand the roles they play in both bulk CdTe and CdTe grain boundaries (GBs). Using first-principles calculations, we systematically study Cu and Cl-related defects in bulk CdTe. We find that Cl has only a limited effect on improving p-type doping and too much Cl can induce deep traps in bulk CdTe, whereas Cu can enhance p-type doping of bulk CdTe. In the presence of GBs, we find that, in general, Cl and Cu will prefer to stay at GBs, especially for those with Te-Te wrong bonds, in agreement with experimental observations.

An Ozone Micro-bubble Technique for Seed Sterilization in Alfalfa Sprouts

The efficacy of ozone micro-bubble water (OMBW) in reducing microbial populations on alfalfa seeds was investigated in this study. We observed the surface of alfalfa seeds using microscopy and found that many cracks and crevices existing on the surface could harbor pathogens. Alfalfa seeds were treated with tap water (TW), micro-bubble water (MBW), ozone water (OW), ozone micro-bubble water (OMBW), and chlorine water (CL) for 5 min, and total microbial population, E. coli and Salmonella spp. colonies were determined. Also, the sterilized seeds were germinated and cultivated for 5 d after sowing to investigate the percentage of germination and the growth of alfalfa sprouts. The treatments with OMBW and CL were most effective in reducing total microbial populations and E. coli was eliminated by OW, OMBW, and CL treatments. CL treatment reduced the percentage of germination and fresh weight of a lfalfa sprouts, but OMBW did not cause any negative effects on the germination and growth of alfalfa sprouts. These results indicate that OMBW can be used as an effective sanitizer for eliminating seed-borne pathogens without detrimental effects on seed viability.

Quality of soil organic matter and C storage as influenced by cropping systems in northwestern Alberta, Canada

Crop rotations and reduction in tillage are commonly recommended for sustained crop production and enhancing soil quality. Our objective was to evaluate the long-term effects of cropping systems (1968–1992) on soil structure, carbon storage and the quality of soil organic matter. The study was conducted on a silt clay loam soil (Typic Cryoboralf) near Beaverlodge, Alberta, The cropping systems were: (a) continuous barley (Hordeum vulgare L.) (CB); (b) continuous bromegrass (Bromus inermiss Leyess.) (CG); (c) continuous forage legume (Medicago sativa L. until 1977, and Trifolium pratense L. since 1978) (CL); and (d) 3 years of bromegrass-legume forage alternating with 3 years of barley (RF). Our data showed that the CG and CL treatments had more stable aggregates with greater mean weight diameter (MWD) than soil under continuous barley. Organic C, total N and the light fraction in soil under CG and CL were higher than those of the other two treatments. Soil under CG had the highest and CB the lowest amounts of acid-hydrolyzable monosacchrides (comprising glucose, arabinose, xylose, mannose and galactose). Higher galactose + mannose concentration in soil under CG indicated a higher soil microbiological activity. Microbial biomass C and N followed the trend among treatments in whole and light fraction organic matter, and total extracted sugars. Soil organic matter 13C-NMR spectroscopy showed that: (i) soil under CB contained the highest amounts of aromatic and the lowest content of aliphatic-C, (ii) soil under CL had the lowest phenolic-C and the least aromaticity, and (iii) soil under CG and RF had the highest amounts of aliphatic-C which includes labile substances such as amino acids and carbohydrates, indicating an improvement in the quality of organic matter. It is concluded that perennial forage crops can improve soil structure and soil organic matter quality and quantity as compared with cereal monoculture.

Enhancement of nitrate reduction by chlorine application in Suaeda salsa (L.) Pall

We have previously reported that one of the mechanisms of growth stimulation of the halophyte Suaeda salsa (L.) Pall by NaCl is partly attributed to increased activity of photosystem II by Cl application. In the present study, the effect of Na and/or Cl application on the reduction and assimilation of nitrate in S. salsa was examined by growing plants in nutrient solutions with the following four treatments: –Na·–Cl, +Na·–Cl, –Na·+Cl and +Na·+Cl at 5 mol m−3. Growth was stimulated by the application of Cl, but not Na. The total amount of nitrogen absorbed did not differ among treatments. However, nitrate accumulation in the plant, particularly in the stem, was much higher in the –Na·–Cl and +Na·–Cl treatments than in the –Na·+Cl and +Na·+Cl treatments. In contrast, the accumulation of crude protein in all plant tissues and of amino acids in the leaves was higher in the –Na·+Cl and +Na·+Cl treatments than in the –Na·–Cl and +Na·–Cl treatments. Thus, nitrate reduction and assimilation were stimulated by Cl application, irrespective of Na application. Increased nitrate reduction was considered to be the main cause of the increased nitrate assimilation induced by Cl. Mechanisms of stimulation of nitrate reduction and assimilation are discussed.

Grazing Impacts on Soil Carbon and Microbial Communities in a Mixed‐Grass Ecosystem

Good management of rangelands promotes C sequestration and reduces the likelihood of these ecosystems becoming net sources of CO2 As part of an ongoing study, soil was sampled in 2003 to investigate the long‐term effects of different livestock grazing treatments on soil organic carbon (SOC), total nitrogen (TN), and microbial communities. The three treatments studied (no grazing, EX; continuously, lightly grazed [10% utilization], CL; and continuously, heavily grazed [50% utilization], CH) have been imposed on a northern mixed‐grass prairie near Cheyenne, WY, for 21 yr. In the 10 yr since treatments were last sampled in 1993, the study area has been subject to several years of drought. In the 0 to 60 cm depth there was little change in SOC in the EX or CL treatments between 1993 and 2003, whereas there was a 30% loss of SOC in the CH treatment. This loss is attributed to plant community changes (from a cool‐season [C3] to a warm‐season [C4] plant dominated community) resulting in organic C accumulating nearer the soil surface, making it more vulnerable to loss. Soil TN increased in the EX and CL treatments between 1993 and 2003, but declined in the CH treatment. Differences in plant community composition and subsequent changes in SOC and TN may have contributed to microbial biomass, respiration, and N‐mineralization rates generally being greatest in CL and least in the CH treatment. Although no significant differences were observed in any specific microbial group based on concentrations of phospholipid fatty acid (PLFA) biomarkers, multivariate analysis of PLFA data revealed that microbial community structure differed among treatments. The CH grazing rate during a drought period altered plant community and microbial composition which subsequently impacted biogeochemical C and N cycles.

Transparent and conducting electrodes for organic electronics from reduced graphene oxide

The deposition and optoelectronic properties of reduced graphene oxide thin films are described. Thin films with thicknesses ranging from 1–10nm have been deposited by the vacuum filtration method. The conductivity of the thin films can be varied over six orders of magnitude by varying the filtration volume of the graphene oxide aqueous suspension while maintaining the transmittance between 60%–95%. In addition, enhancement in the conductance through Cl doping is demonstrated. The combination of the reduction and Cl treatments make the reduced graphene oxide thin films sufficiently conducting to incorporate them as the hole collecting electrode in proof of concept organic photovoltaic devices.

Leachability and Phytoavailability of Nitrogen, Phosphorus, and Potassium from Different Bio‐composts under Chloride‐ and Sulfate‐Dominated Irrigation Water

Concerns over increased phosphorus (P) application with nitrogen (N)-based compost application have shifted the trend to P-based composed application, but focusing on one or two nutritional elements does not serve the goals of sustainable agriculture. The need to understand the nutrient release and uptake from different composts has been further aggravated by the use of saline irrigation water in the recent scenario of fresh water shortage. Therefore, we evaluated the leachability and phytoavailability of P, N, and K from a sandy loam soil amended with animal, poultry, and sludge composts when applied on a total P-equivalent basis (200 kg ha(-1)) under Cl(-) (NaCl)- and SO4(2-) (Na2SO4)-dominated irrigation water. Our results showed that the concentration of dissolved reactive P (DRP) was higher in leachates under SO(4)(2-) than Cl(-) treatments. Compost amendments differed for DRP leaching in the following pattern: sludge > animal > poultry > control. Maize (Zea mays L.) growth and P uptake were severely suppressed under Cl(-) irrigation compared with SO4(2-) and non-saline treatments. All composts were applied on a total P-equivalent basis, but maximum plant (shoot + root) P uptake was observed under sludge compost amendment (73.4 mg DW(-1)), followed by poultry (39.3 mg DW(-1)), animal (15.0 mg DW(-1)), and control (1.2 mg DW(-1)) treatment. Results of this study reveal that irrigation water dominated by SO4(2-) has greater ability to replace/leach P, other anions (NO3(-)), and cations (K+). Variability in P release from different bio-composts applied on a total P-equivalent basis suggested that P availability is highly dependent on compost source.

Effect of Chloride and Soybean Cultivar on Yield and the Development of Sudden Death Syndrome, Soybean Cyst Nematode, and Southern Blight

Yields of irrigated soybean in Arkansas are threatened by two problems: chloride toxicity and sudden death syndrome (SDS). Soybeans are sensitive to chloride, which accumulates in the upper soil profile when water with high salt content is used for irrigation. Sudden death syndrome is a soilborne disease often associated with well-irrigated fields. Even though these problems both affect irrigated soybeans, there are no reports on the effect of chloride toxicity on SDS. To determine if there is an effect of chloride toxicity on SDS, a test was established at the Cotton Branch Station, Marianna, AR, in 1995 and 1996. Four cultivars were selected that were either susceptible to SDS (S) or resistant to SDS (R) and either translocated chloride to the leaves (includer, I) or confined chloride in the roots (excluder, E). The cultivars were Hartz 6686 (SE), Terra Vig 6653 (SI), Hartz 6200 (RE), and Asgrow 6297 (RI). Soil chloride concentrations were adjusted by the addition of KCl. Before planting, KCl was applied to achieve the recommended concentration of K over the entire field. At V4, chloride treatments were applied by either adding no additional KCl (low Cl) or adding 1,120 kg of KCl per ha (moderate Cl) or 2,240 kg of KCl per ha (high Cl). Soil samples were taken within the center two rows of each plot at planting, flowering (R2), and harvest and assayed for populations of Fusarium solani and Heterodera glycines. Soil chloride concentrations were determined at R2, and leaf chloride levels were determined at R3. Weekly disease ratings were made on SDS and converted to area under the disease progress curve (AUDPC). Plant lodging and the incidence of southern blight (Sclerotium rolfsii) were determined during mid-reproductive growth. Leaf chloride concentrations were influenced by both chloride treatment and cultivar: elevated concentrations occurred with the includer cultivars in the moderate and the high Cl treatments. Soil concentrations of chloride reflected the chloride treatments in 1995, but not 1996. Soil populations of F. solani did not respond consistently to either chloride treatment or cultivar; however, H. glycines egg densities increased with increased soil chloride treatments in Hartz 6686 (SE) and Terra Vig 6653 (SI) at R2, but not at harvest. Increased soil chloride treatments increased SDS in both years with Hartz 6686 (SE), but did not affect this disease in the other cultivars. Higher soil chloride treatments decreased yield in all cultivars except Hartz 6200 (RE) in 1996. Although Terra Vig 6653 (SI) did not develop severe levels of SDS foliar symptoms, it did have increased lodging and significant increases in southern blight with moderate and high soil chloride treatments. These results indicate that growers with fields that have both elevated concentrations of soil chloride and SDS should select SDS-resistant excluder cultivars to minimize yield losses due to both problems.

Acclimation response of spring wheat in a free-air CO(2) enrichment (FACE) atmosphere with variable soil nitrogen regimes. 3. Canopy architecture and gas exchange.

The response of whole-canopy net CO(2) exchange rate (CER) and canopy architecture to CO(2) enrichment and N stress during 1996 and 1997 for open-field-grown wheat ecosystem (Triticum aestivum L. cv. Yecora Rojo) are described. Every Control (C) and FACE (F) CO(2) treatment (defined as ambient and ambient +200 mumol mol(-1), respectively) contained a Low- and High-N treatment. Low-N treatments constituted initial soil content amended with supplemental nitrogen applied at a rate of 70 kg N ha(-1) (1996) and 15 kg N ha(-1) (1997), whereas High-N treatments were supplemented with 350 kg N ha(-1) (1996 and 1997). Elevated CO(2) enhanced season-long carbon accumulation by 8% and 16% under Low-N and High-N, respectively. N-stress reduced season-long carbon accumulation 14% under ambient CO(2), but by as much as 22% under CO(2) enrichment. Averaging both years, green plant area index (GPAI) peaked approximately 76 days after planting at 7.13 for FH, 6.00 for CH, 3.89 for FL, and 3.89 for CL treatments. Leaf tip angle distribution (LTA) indicated that Low-N canopies were more erectophile than those of High-N canopies: 48 degrees for FH, 52 degrees for CH, and 58 degrees for both FL and CL treatments. Temporal trends in canopy greenness indicated a decrease in leaf chlorophyll content from the flag to flag-2 leaves of 25% for FH, 28% for CH, 17% for CL, and 33% for FL during 1997. These results indicate that significant modifications of canopy architecture occurs in response to both CO(2) and N-stress. Optimization of canopy architecture may serve as a mechanism to diminish CO(2) and N-stress effects on CER.

Corn Responses to Chloride in Maximum Yield Research

AbstractChloride nutrition of corn (Zea mays L.) was investigated to determine if Cl limits production in high‐yield environments. Experiments were conducted to evaluate the effects of Cl fertilization on a Freehold sandy loam (fine‐loamy, mixed, mesic Typic Hapludults) near Adelphia, NJ, using irrigation and intensive crop production practices. Corn was grown at 107 600 plant ha−1 with equidistant spacing. All plots received 454 kg K ha−1 using KOH, K2SO4, or KCl to establish five treatments: 0, 50, 100, 200, and 400 kg Cl ha−1. Positive responses of corn to added Cl were observed each year. In 1990, the Cl treatments averaged 1.1 Mg ha−1 more grain than the check yield of 11.3 Mg ha−1 (P = 0.08). In 1991, the check yield was 19.0 Mg ha−1 and the response to Cl was linear up to the 400 kg ha−1 rate, which yielded 20.5 Mg ha−1. In 1992, the Cl treatments averaged 0.5 Mg ha−1 more grain than the check yield of 14.5 Mg ha−1 (P = 0.07). Grain yields were positively correlated with increases in ear‐leaf Cl concentration. Increases in grain yield were associated with increased ear size. Chloride did not increase stover yield. A linear decrease in incidence of stalk rot with Cl rate was observed in 1992. Results suggest that, when produced in high‐yield environments, corn may respond to enhanced levels of Cl nutrition.

Nitrification in high chloride zones near fertilizer bands in a calcareous soil

Abstract The effect of high chloride (Cl) on nitrification of ammonium‐nitrogen (NH4‐N) in zones surrounding applied fertilizer and on nitrogen (N) uptake by sorghum [Sorghum bicolor L. (Moench)] was examined in a calcareous silt loam soil. Fertilizer N was applied at a rate of 120 mg N/kg as ammonium sulfate [(NH4)2SO4] or ammonium chloride (NH4Cl) and supplemented by calcium chloride (CaCl2) to provide a final Cl concentration of 350 or 700 mg Cl/kg to simulate a concentrated point placement. Soil around the point of fertilizer placement and shoot dry matter (if present) were sampled and analyzed at 1,7,14, 24, 34, and 44 days after application. Soil pH within 2.0 cm from the fertilizer placement point for the Cl treatments was below the bulk soil pH during the entire study due to the effect of adding CaCl2. Beyond the fertilizer placement zone, soil pH for the ammonium sulfate treatment without Cl increased initially to near pH 8.5 then declined steadily with time as acidification from nitrification in...

Processing parameters and kinetics of bromination and chlorination in the YBa/sub 2/Cu/sub 3/O/sub 6+x/ system

The introduction of halogens such as Cl/sub 2/ and Br/sub 2/ can restore 90 K superconductivity to oxygen deficient YBa/sub 2/Cu/sub 3/O/sub 6+x/. This is potentially important for applications to thin-film devices due to the low processing temperatures required relative to reprocessing with oxygen. Low-temperature (260 degrees C) and short-time (>5 min) bromination has been shown to convert initially insulating YBa/sub 2/Cu/sub 3/O/sub 6.2/ powder to a high-temperature superconductor with properties similar to the standard O/sub 7/ material. This process has now been extended to single crystals as well, but with somewhat different processing parameters. Thermal gravimetric analysis (TGA) coupled with mass spectrometry indicated that the Br becomes strongly bonded with no release of Br observed in taking powder samples to 1000 degrees C in flowing forming gas (2%H/sub 2//98%N/sub 2/). The reaction has also been found to be highly exothermic for both Br and Cl treatments, which is consistent with the strong bonding of the bromine.

Chloride and water stress effects on soybean in pot culture

Abstract Chloride (Cl) toxicity in susceptible soybean (Glycine max (L.) Merr.) cultivars is caused by excessive uptake of Cl but the minimum concentration of soil Cl required to produce phytotoxicity is unknown. Also there is no evidence to indicate whether Cl toxicity can be induced in soybean cultivars designated as Cl tolerant under field conditions. Since the severity of the Cl problem appears to be accentuated by limited rainfall, there was a need to evaluate water stress effects with Cl rates on a susceptible cultivar. Potassium chloride solution was the source of Cl in each of three pot experiments using a Leefield sand (arenic Plinthaquic Paleudult). Experiment 1 evaluated treatments of 0, 91, 182, 364, and 728 mg Cl/kg of soil using a Cl susceptible cultivar. Experiment 2 compared treatment effects of 0, 300, and 600 mg Cl/kg of soil with four Cl susceptible and four Cl tolerant cultivars. In experiment 3, the effects of water stress treatments (none, medium, and high) and Cl treatments of 0, 100, 200, 300 and 400 mg/kg of soil were evaluated with a Cl susceptible cultivar. Increased amounts of applied Cl increased leaf scorch symptoms (Cl toxicity), shoot and seed Cl, and decreased shoot and seed weight of ‘Bragg’ soybean (experiment 1). The lowest rate of Cl (91 mg/kg) induced phytotoxicity. Concentrations of Cl in leaves, stems, and pods increased with increased Cl rate for both tolerant and susceptible cultivars, but levels were higher in susceptible cultivars (experiment 2). However, root Cl of tolerant cultivars was higher than that of susceptible cultivars where Cl was applied. Phytotoxicity was induced in susceptible and tolerant cultivars by 300 and 600 mg Cl/kg of soil, respectively. Water stress increased defoliation and decreased pod weight but had no significant effect on phytotoxicity or tissue Cl concentration of ‘Cobb’ soybean (experiment 3). Leaf scorch, defoliation, and concentrations of Cl in leaves, stems, and pods were increased and water usage and pod weight were decreased by increased Cl rate. Cl toxicity was induced by Cl application in cultivars previously designated as Cl tolerant under field conditions and root Cl was higher in tolerant than susceptible cultivars. Therefore, there remains a need to establish the range in soil Cl required to identify Cl tolerant and susceptible cultivars under greenhouse conditions and to study the mechanism for genetic control of Cl sensitivity in soybean cultivars.

Chloride effects on corn

Abstract Chloride (Cl) toxicity was suspected in corn (Zea mays L.) growing in a poorly‐drained Atlantic Coast Flatwoods soil where Cl toxicity of soybean {Glycine max (L.) Merr.} was a problem. Field and greenhouse research was conducted with rates of applied Cl in an effort to induce Cl toxicity in corn. ‘Trojan 114’ corn was grown in the greenhouse with Cl rates (KCl) of 0, 364, and 728 ug/g and in the field with rates of 0, 85, 170, and 340 kg/ha. Potassium sulfate (K2SO4) treatments were included to supply equivalent amounts of K as that in KCl. Phytotoxicity of corn did not occur in greenhouse or field experiments with any fertilizer treatment. In the greenhouse Cl concentrations in 26‐day old corn plants grown in a poorly‐drained Flatwoods soil (Leefield sand ‐ arenic Plinthaquic Paleudult) for the 0 and 728 ug Cl/g treatments were 5.0 and 32.7 g/kg in shoots, 1.6 and 14.9 g/kg in ear leaves, and 1.3 and 16.5 g/kg in stalks, respectively. In the field, Cl treatments applied to corn grown in a poorly‐drained Flatwoods soil (Alapaha sand ‐ arenic Plinthic Paleaquults) were not as effective in increasing Cl concentrations in shoots and ear leaves as that for corn grown in a well‐drained soil (Tifton loamy sand ‐ thermic Plinthic Paleudult) apparently because of the greater amount of residual soil Cl in the poorly‐drained soil. Concentrations of Cl in shoots of corn receiving O and 340 kg Cl/ha were 3.8 and 18.0 g Cl/kg, respectively, for corn grown in the well‐drained soil and 16.1 and 18.0 g Cl/kg, respectively, for corn grown in the poorly‐drained soil. Grain yields were not affected by fertilizer treatments on either soil and Cl concentration in grain for corn grown in the Tifton soil was not different among treatments. These data indicate that corn is not very susceptible to high levels of soil Cl.

Chloride Toxicity of Soybeans Grown on Atlantic Coast Flatwoods Soils1

AbstractLeaf scorch, caused by CI toxicity, affected over 20,000 ha of soybeans (Glycine max (L.) Merr.) in 1980 in the poorly‐drained Flatwoods soils of Georgia. This new disorder, compounded by the extended drought of 1980, resulted in Severe yield reductions of ‘Bragg’ soybeans. Field studies involving fertilizer treatments in two experiments and 15 cultivars in one experiment were conducted in 1981 to determine the cause of the problem. Phosphorus, Mg, and Cl treatments were evaluated on two problem areas—a Leefield sand (arenic Plinthaquic Paleudults) and an Alapaha sand (arenic Plinthic Paleaquults). Cultivars also were evaluated on the Alapaba sand. Leaf scorch developed on plants receiving Cl containing fertilizer and on 5 of 15 cultivars. Symptoms observed were the same as those described for Cl toxicity. Leaf and seed Cl levels averaged 0.12% and 75 µg/g, respectively, for plants receiving no KCl fertilizer compared to 0.94% and 166 µg/g for plants receiving KCl. Leaf and seed Cl levels averaged 1.67% and 682 µg/g, respectively, for five susceptible cultivars compared to 0.09% and 111 µg/g for 10 tolerant cultivars. The parent seed of each cultivar contained relatively low levels of Cl, indicating that susceptible cultivars are not high Cl accumulators when grown under low Cl soil conditions. Leaf scorch ratings were positively correlated with leaf and seed Cl and negatively correlated with seed weight and yield. The leaf scorch problem on susceptible cultivars apparently is caused by a Cl buildup in poorly‐drained Flatwoods soils. The major source of Cl appears to be KCl fertilizer.

Effects of Salts and Application Methods on English Ivy1

Abstract Na2SO4, K2SO4, NaCl, KCl or CaCl2 at concentrations of 0.25N were applied daily as a soil drench or foliar spray to established plants of English ivy (Hedera helix L.). Marginal leaf necrosis developed after 28 days on plants drenched with Cl salts although necrosis was evident after 7 days and the injury was more severe on plants sprayed with Cl salts. Shoot dry weights of plants treated with Cl salts were significantly less than those of control or spray SO4 treatments. Leaf necrosis was not evident on plants drenched with SO4 salts, but shoot dry weights were significantly less than those of plants sprayed with SO4 salts or water. Shoot Na was greater from spray-applied Na salts compared to soil-treatments while shoot Cl was greater in soil-treated plants compared to spray Cl treatments. Shoot Cl generally corresponded with the severity of plant injury whereas shoot Na did not.

AB initio calculation of vertical transition energies of the C 2H 2 molecule

Various ab initio SCF and Cl treatments are reported for the acetylene molecule in ground and excited states at its fixed linear equilibrium geometry. The results speak in favor of the former analysis of the vacuum UV absorption spectra of C 2H 2 given by Wilkinson according to which above the X̃C state an allowed transition to a linear upper state (X̃D) and two allowed transitions with broad bands (X̃E and X̃F) to non-linear upper states are present. The calculated order and spacing of the excited states does not support the new analysis given by Jungen according to which only one allowed transition (X̃F) and a forbidden one to a linear upper state (X̃D) should appear between 1250 and 1360 A.

The Effect of Chloride and Lime on the Manganese Uptake by Bush Beans and Sweet Corn

AbstractThe effect of chloride and lime on the uptake of Manganese by bush beans (Phaseolus vulgaris) and sweet corn (Zea mays var. rugosa) was investigated under field and greenhouse conditions. Lime and Cl treatments were applied in factorial combinations in both field and greenhouse experimens. Lime was applied at rates up to 3 tons/acre with Cl applied at rates up to 90 lb/acre. All treatments received blanket applications of N, P, and S.The Mn content in the trifoliate bean leaves was high enough to explain the toxicity symptoms observed. At the zero lime rate all applications of chloride resulted in Mn levels > 1,000 ppm. Increasing levels of Cl increased the level of Mn in all cases. The level of Mn at the zero Cl treatment and with added lime was below suggested toxic levels. The application of lime always reduced the Mn content.The application of KCl increased the Mn content of the sweet corn plants, whereas the application of K2SO4 or K2CO3 had no effect on the Mn content.

Effects of Soil Moisture Tensions and of Chloride and Sulfate Treatments upon the Yield, Composition, and Bacterial Soft Rot of Irish Potatoes

AbstractGreenhouse experiments were conducted over a period of 2 years to determine the effects of soil moisture and of the chloride and sulfate ions upon the growth and quality of potato tubers.Irish cobbler potatoes were grown in a soil mixture containing equal weights of Bladen fine sandy loam and 18‐mesh quartz sand. The anion variables consisted of KCl or K2SO4 applied at the rate of 180 pounds K2O per acre. The different moisture levels consisted of resaturating the soil when tensions of approximately 300, 800, 2,000 and 10,000 cm. of water were obtained. Measurements of yield, chemical composition, dry matter, specific gravity of tubers, and susceptibility of tubers to bacterial soft rot were made at or after harvest.The yields of U. S. No. 1 tubers from the SO4‐treated plots were greater than those receiving Cl. There were some suggestions that the response to high levels of soil moisture may have been related to the source of potassium. Greater vine yields were obtained with the chloride treatments than with the sulfate. A reversal in the curve for growth of tops occurred at the lowest level of soil moisture. The use of chloride as compared to sulfate increased the content of Ca and Mg in the leaves and stems and decreased the content of Mg in the tubers. The K contents of tubers were greater with the SO4 than with the Cl treatments but no differences in K content of leaves were associated with source of potassium. Applications of SO4 as compared to Cl at all moisture levels resulted in increased contents of N in the leaves, stems, and tubers. No significant differences in the specific gravity of tubers as related to Cl and SO4 treatments were found after 6 weeks storage. The mean specific gravities of U. S. No. 1 tubers increased with increasing levels of soil moisture. The dry matter contents of leaves and stems were greater from the sulfate treated plants than from the chloride. Wound infection by bacterial soft rot organisms was less for tubers grown under low soil moisture tensions, than those grown under high tensions. The rate of bacterial decay of tubers grown under low moisture tensions was greater than for those grown under the limiting conditions of low soil moisture.