Effect of nitrogen and potassium fertilization on strawberries in an annual hill culture system: 1. Yield and fruit size

Abstract

A field trial showed that strawberries do not need large quantities of N and that N applied in spring had the biggest influence on yield. Plants receiving spring N yielded 43.1 t ha^‐1 compared with 26.0 t ha^‐1 by plants not receiving spring N. Although N applied in autumn did not influence yield to a marked extent, it caused a shift in production peaks. Plants that had received autumn N produced an early crop, while plants receiving no autumn N showed a delayed production peak. Highest yields were obtained with 36.5 kg N ha^‐1 in the spring, and 36.5 kg N ha^‐1 in autumn in split applications. For optimum yields, N should be applied from mid‐winter in small, regular amounts. Although yield was not greatly affected by K applications, it is essential to keep the soil K content at about 40 ppm Bray II extractable K in order to obtain better fruit size.     

Effects of nitrogen carriers,nitrogen rates,and maturity on composition of smooth bromegrass

Abstract

Magnesium and Ca concentrations in smooth bromegrass (Bromus inermis L) were not affected by late‐winter applications of N. Magnesium concentrations were constant until rapid growth in mid‐May then they declined until early June harvest. Highest seasonal concentrations were found in the fall regrowth. Calcium concentrations declined as plants matured in spring. Highest seasonal Ca concentrations were found in the fall regrowth. Nitrogen, P, and K concentrations and K/(Ca+Mg) ratios were increased by N applications during early spring but did not differ significantly by early June harvest. Nitrogen and P concentrations decreased as plants matured in spring and fall. K concentrations and K/(Ca+Mg) ratios changed inconsistently from sampling date to sampling date. Forage yields were approximately doubled by 67 kg N/ha and tripled by 202 kg N/ha. Significant yield differences were related to different N carriers.     

Effect of potash fertilizer on leaf nutrients and their relationships to tuber yields of sweet potato

Abstract

The fourth, fully‐expanded leaves at sweet potato vine tips were sampled at harvest from two separate but similar experiments on njala upland soils after 7 years bush fallow to study the effects of timing and rates of K fertilizers on leaf nutrients and their relationships to sweet potato tuber yields. Potash showed significant effects on leaf P, leaf Zn, leaf Ca, leaf Mn, leaf K/P and leaf Ca/Mg. K x timing interaction affected leaf K/Mg and leaf K/P but timing of Z application did affect significantly neither leaf nutrients nor leaf nutrient ratios. Significant quadratic effect of K on tuber yields as well as significant cubic K x timing interaction effect on tuber yields were observed. There were significant negative correlations between tuber yields and leaf N and between tuber yields and leaf P, indicating that increases in either leaf N or leaf P depressed yields. On the basis of coefficient of determination, increases in leaf N contributed significantly more to yield variation than increases in leaf P. Analysis of covariance and multiple regression studies showed lack of significance of 10 nutrients on tuber yields. Sweet potato tissue which reflects differential nutrient levels with significant effect on tuber yields must be sought. Apart from the added fertilizer, the total effect of ether factors which affect nutrient status and crop performance must be considered.     

Effect of phosphorus,nitrogen fertilization and foliar applied manganese on yield and nutrient concentration of soybean

Abstract

A greenhouse experiment was conducted on clay loam soil of pH 7.8 to evaluate the effect of P, N fertilization and foliar applied Mn on yield and nutrient concentration in leaves and seeds of soybean. A significant yield increase was obtained for each added increment of P fertilizer up to 30 kg P₂O₅/acre. At application rates of 0, 15, 30 & 45 kg P₂O₅/acre, the seed yield was subsequently 27.8, 65.8, 82.8 & 83.6% of the maximum yield obtained at the maximum calculated P level. The yield increase accounted 14.2 and 10.2% for N and Mn applications. In all treatments, in which P was combined with N, the seed yield was relatively higher than with P or N applied alone.

Phosphorus, N and Mn content in leaves and seeds were positively correlated with the applied nutrient fertilizers. At any given level of applied P and Mn, P content was significantly higher in +N than ‐N treatments. By Mn application, P content in leaves and seeds was decreased. Phosphorus and Mn applications did not influence N content in leaves and seeds.     

Plant Density and Hybrid Impacts on Corn Grain and Forage Yield and Nutrient Uptake

ABSTRACT

Corn (Zea mays L.) production recommendations should be periodically evaluated to ensure that production practices remain in step with genetic improvements. Since most of the recent increases in corn grain yield are due to planting at higher densities and not to increased per-plant yield, this study was undertaken to measure the effects of plant density and hybrid on corn forage and grain yield and on nutrient uptake. Plant density (4.9, 6.2, 7.4, and 8.6 seeds m^?2) and hybrid relative maturity (RM) [early (108 day RM); medium (114 day RM); and late (118 day RM)] combinations were evaluated over five site-years under irrigated and non-irrigated conditions. The interaction of hybrid with plant density was never significant for grain, stem, or leaf biomass. The latest RM hybrid out-yielded the medium and early hybrids by 550 and 1864 kg ha^?1, respectively. Grain yield was highest at 8.6 plants m^?2. Total stem yield was also greatest at the highest plant density but by only 340 kg ha^?1 more than at 7.4 seeds m^?2. Based on grain yield response over sites, the estimated optimum density was 7.6 seeds m^?2, which is 0.7 seeds m^?2 higher than the current recommendation at this average yield level (11.5 Mg ha^?1). Grain nitrogen (N), phosphorus (P), and potassium (K) uptakes were highest for the medium RM hybrid. Nutrient uptake levels varied by planting density, with the lowest levels observed at the lowest and highest plant densities. At 4.9 seeds m^?2, the reduced uptake is explained by lower biomass yields. At the 8.6 seeds m^?2 rate, N and K levels may have been lower due to dilution.     

Effect of seed phosphorus concentration on nodulation and growth of three common bean cultivars

Abstract

An experiment was conducted in the greenhouse to evaluate the effects of seed phosphorus (P) concentration on growth, nodulation, and nitrogen (N) and P accumulation of three common bean (Phaseolus vulgaris L.) cultivars. Seeds were produced under low or high soil P levels, and soaked, or not, in 200 mM KH₂PO₄ solution. The experiment had a 3×3×2×2 factorial block design: three cultivars (ICA Col 10103, Carioca and Honduras 35), three levels of applied P (15, 30 and 45 mg P kg^?1 soil), two native seed P concentrations, and two seed soaking treatments. Plants were harvested at flowering. Soaked seeds increased the number, dry mass and P content of nodules, but did not affect plant growth. Plants originated from seeds with high native P concentration presented higher shoot dry mass and nodule number and mass at every soil P level, and were less responsive to increased soil P supply, than plants from low seed P. In plants from seeds with high P, soil P levels did not alter significantly root dry mass, while in plants from seeds with low P bean cultivars expressed wider differences in root dry mass. The genotypic variability of nodulation was influenced by soil P levels and seed P concentration. Both higher soil or seed P supply enhanced N and P accumulation in shoots. These results indicate that a high seed P concentration produces plants less dependent on soil P supply, and can enhance nodulation and N₂ fixation of common bean. Seed P supply affected the cultivar performance, and should be considered in evaluation of bean genotypes.     

Quality,yield and nitrogen fixation of faba bean seeds as affected by sulphur fertilization

Abstract

Faba bean (Vicia faba L.) is an important source of plant protein for humans and animals; however, nutritional value of seeds is notoriously deficient in sulphur (S)-containing amino acids. In this article, the effect of S fertilization on faba bean's capability of N₂ fixation, grain yield and chemical characteristics in terms of protein fractions, fatty acids and minerals composition is reported. A randomized, complete block design with three replicates was used, and three S applications (0, 30 and 60 kg ha^?1, respectively) for faba bean were performed. The S fertilization was split into two applications: 50% before sowing and 50% in the beginning of March as K₂SO₄. At the same time, both the legume and oat crops were fertilized uniformly with 10 kg N ha^?1 as ¹⁵N NH₄ ¹⁵NO₃ (10% ¹⁵N atomic excess) in solution form. In a Mediterranean climate under optimal spring rainfall situations, faba bean produced high yield of grain and protein. Sulphur application resulted in an increase in overall plant yield and N₂ fixation. In addition, S fertilization enhanced the protein quality, increasing its degradable fraction. Fertilizing faba bean with 30 kg ha^?1 of S resulted in a more appropriate dose in order to obtain a quantitative and qualitative crop improvement. From our findings, it can be concluded that S fertilization to faba bean should be recommended to soils with suboptimal S levels to obtain maximum seed and protein yields.     

Foliar fertilization of soybeans (Glycine max L.)

Abstract

The effects of foliar fertilizer applications to soybeans during seed‐filling were examined using a complete factorial design with four levels each of nitrogen (N), phosphorus plus potassium (P+K) and sulfur (S). Hodgson soybeans were planted in 76‐cm rows on a Piano silt loam (Typic Argiudoll) in 1976 and 1977. Four fertilizer spray applications were made at 7‐ to 10‐day intervals beginning at stage R₄ ². The application of N generally increased yield, seed weight, and percent N in the grain both years of the experiment. Phosphorus, K, and S had little influence on the parameters measured. Leaf burn after each fertilizer application was significantly increased by most levels of fertilizer addition.     

Effects of foliar fertilization on yield,protein, oil and elemental composition of two soybean varieties

Abstract

The effects of foliar fertilization on the yield and seed composition of two soybean (Glycine max L. Merrill) varieties were investigated under mid‐Missouri conditions over a 2‐year period. The foliar fertilizer treatments consisted of (i) 80–8–24–4 (NPKS) kg/ha, (ii) 40–4–12–2 (NPKS) kg/ha, and (in) control (no foliar treatment) with the optimum proportion of N:P:K:S in the solution 10:1:3:0.5 respectively. Nutrient sources were urea, potassium polyphosphate, and potassium sulfate. Water solutions of fertilizers (pH 6.9) containing 0.1% Tween 80 (v/v) were sprayed on the plants using a CO₂ ‐ pressurized back‐pack sprayer. Foliar fertilizer was split between four equal applications during the seed filling period. The variety Mitchell at the higher rate and the variety Williams at the lower fertilizer application rate produced slight, though statistically insignificant, yield increases. At the higher rate of application, the seed protein contents of both varieties increased, while the oil contents decreased. The concentrations of P and K in the seeds were not affected by foliar fertilization, but at the higher rate, there was a small decrease in S content of Williams variety.     

Effects of Nitrogen and Phosphorus Fertilizers and Intercropping on Uptake of Nitrogen and Phosphorus by Wheat,Maize, and Faba Bean

Abstract

One‐third of all the cultivated land area is used for multiple cropping and half of the total grain yield is produced with multiple cropping in China. There have been numerous studies on nutrient acquisition by crops in legume/non‐legume intercropping systems, but few on nutrient uptake in cereal/cereal intercropping. This paper describes a field experiment in which integrated wheat/maize and maize/faba bean systems were compared with sole wheat and sole faba bean cropping to assess the effects of intercropping on nutrient uptake by wheat, maize, and faba bean under various application rates of nitrogen (N) and phosphorous (P) fertilizers. Results show that both N and P fertilizers and intercropping enhanced N uptake by wheat, while only P fertilizer and intercropping increased P acquisition by wheat. The advantage of N uptake by border rows of wheat intercropped with maize declined with increasing N fertilizer application rate, but that of P acquisition was not affected by P fertilizer. The amounts of both N and P taken up by maize intercropped with faba bean were much higher than those by maize intercropped with wheat throughout the period of intercropping. Both fertilization and intercropping did not influence the N and P uptake by faba bean.     

Use of velvet bean to improve soil fertility and weed control in corn production in northern belize

Abstract

The objective of this research was to mesasure the effect of intercropping corn (Zea mays L.) with velvet bean (Mucuna pruriens) oil corn yields, soil fertility, and weed control in northern Belize. Two soils were used which are widespread in the area. These soils are high in clay (simectitc) and are well supplied with bases. One soil, the Louisville, has a black surface horizon overlying light gray to white calcareous weathered coral. The other soil was Xaibe which consists of a reddish‐brown clay over hard limestone “cap rock”; at 30–40 cm. Both soils had a relatively high organic carbon (C) and total nitrogen (N) content. We classified the Louisville as Calciustert and the Xaibe as a Ustropept. The treatments used (carried out annually in 1990, 1991, and 1992) were residue burn (B), bum plus fertilizer (BF), a velvet bean intercrop (G), and a velvet bean intercrop plus fertilizer (GF). Velvet bean intercropping did not have a positive effect on corn yields on these soils. For adequate yields to be maintained, it appears that fertilization with N, phosphorus (P), potassium (K) and certain micronutrients are required. We did obtain some indication that velvet bean intercropping will reduce weed population, including a serious infestation of cogongrass (Jmperata cylindrica). Velvet bean did not maintain the soil N content Corn yields decreased on the Louisville soil at San Victor from a range of 2,804 kg/ha to 3,181 kg/ha in 1990 to 1,783 kg/ha to 2,065 kg/ha in 1992. There were no significant treatment effects in any year. With the Xaibe soil, no yields were obtained in 1990 because of weed competition. In 1991, yields ranged from 555 kg/ha to 1,146 kg/ha (no significant treatment effects). In 1992, the fertilized plots, BF and GF, had corn yields of 1,391 kg/ha and 1,592 kg/ha, respectively. The unfertilized plots, B and G, had corn yields of 751 kg/ha and 699 kg/ha, respectively. We did obtain sufficient information valuable for persons making fertilizer recommendations on similar types of soil. The Mehlich 3 and the ammonium bicarbonate‐DTPA extractant (the latter extractant similar to that used in Belize) did not give good correlations between P and K leaf levels and corn yields. Where soil test P and K were often adequate, corn ear leaf levels were deficient (and presumably yields were reduced because of this metabolic deficiency). We concluded from both soil tests and leaf analyses that the micronutrients copper (Cu), manganese (Mn), and molybdenum (Mo) are seldom, if ever, limiting plant growth and grain yield, although there appears to be seasonal differences. With both soils, soil tests were not good indicators of zinc (Zn) concentrations in the leaf. In 1992, soil tests indicated adequacy of this element, although leaf Zn was deficient in all plots on the Louisville soil in 1990, most plots in 1992, and several plots on the Xaibe soil in both years.     

Wheat response to N2 fixed by faba bean (Vicia faba L.) as affected by sulfur fertilization and rhizobial inoculation in semi‐arid Northern Ethiopia

Nitrogen fixation in faba bean (Vicia faba cv. Mesay) as affected by sulfur (S) fertilization (30 kg S ha^–1) and inoculation under the semi‐arid conditions of Ethiopia was studied using the ¹⁵N‐isotope dilution method. The effect of faba bean–fixed nitrogen (N) on yield of the subsequent wheat crop (Triticum aestivum L.) was also assessed. Sulfur fertilization and inoculation significantly (p < 0.05) affected nodulation at late flowering stage for both 2004 and 2005 cropping seasons. The nodule number and nodule fresh weighs were increased by 53% and 95%, relative to the control. Similarly, both treatments (S fertilization and inoculants) significantly improved biomass and grain yield of faba bean on average by 2.2 and 1.2 Mg ha^–1. This corresponds to 37% and 50% increases, respectively, relative to the control. Total N and S uptake of grains was significantly higher by 59.6 and 3.3 kg ha^–1, which are 76% and 66% increases, respectively. Sulfur and inoculation enhanced the percentage of N derived from the atmosphere in the whole plant of faba bean from 51% to 73%. This corresponds to N₂ fixation varying from 49 to 147 kg N ha^–1. The percentage of N derived from fertilizer (%Ndff) and soil (%Ndfs) of faba bean varied from 4.3% to 2.8 %, and from 45.1% to 24.0%, corresponding to the average values of 5.1 and 47.9 kg N ha^–1. Similarly, the %Ndff and %Ndfs of the reference crop, barley, varied from 8.5 % to 10.8% and from 91.5% to 89.2%, with average N yields of 9.2 and 84.3 kg N ha^–1. Soil N balance after faba bean ranged from 13 to 52 kg N ha^–1. Beneficial effects of faba bean on yield of a wheat crop grown after faba bean were highly significant, increasing the average grain and N yields of this crop by 1.11 Mg ha^–1 and 30 kg ha^–1, relative to the yield of wheat grown after the reference crop, barley. Thus, it can be concluded that faba bean can be grown as an alternative crop to fallow, benefiting farmers economically and increasing the soil fertility.     

Presowing soaking of wheat seeds in copper and manganese solutions

Abstract

Presowing soaking of wheat seeds in CuSO₄ and MnSO₄ solutions increased the grain yield with increasing concentrations of these solutions. Seed soaking in 0.1% CuSO₄ or 0.2% MnSO₄ solution for 12 hrs gave the highest grain yield. The Cu and Mn content of the grain increased with increasing concentrations of these solutions. Whereas N and P contents were not significantly affected, but K content increased significantly due to the Cu treatment.     

Effect of peach root residues,lime and supplemental nitrogen on survival and yield of peach trees in a decline area

Abstract

Supplemental N fertilization significantly increased survival and yield of Elberta peach trees growing in a severe decline area. There was a trend for supplemental N plus dolomitic lime to give further increases in tree survival and individual tree yields but did not significantly influence nutrient content of leaves. Trees did not respond to peach root residue applications.     

Nutrient Utilization Indices of NPK and Drought Management in Groundnut under Sandy Soil Conditions

ABSTRACT

In arid zones, farmers are obligated to reduce water amounts used in irrigating their lands. Consequently, reduction in final yields is realized. Thus, dealing with such a case became a decisive act. We tried to investigate the acceptable degree of lowering irrigation water with sustaining the productivity of groundnut as a way for managing drought conditions. Therefore, in summer seasons of 2016 and 2017 at the Experimental Research and Production Station, National Research Centre, Egypt, field trials were conducted with growing groundnut plants under three irrigation levels, i.e., 50%, 75%, and 100% of crop evapotranspiration (ET_c), denoted as I₅₀, I₇₅, and I₁₀₀, respectively. N, P, and K contents in seed and shoot and their yields in addition to harvest and partitioning indices were estimated. In spite of irrigating groundnut plants by normal water amounts, I₁₀₀, caused the maximum weight of seed biomass yield ha?1 and seed N and P contents, I75 was similar to I₁₀₀ for producing shoot biomass yield ha?1 and seed K content. Moreover, N and P yields (for shoots and seeds) and k yield (for seeds) showed the maximum values with I₁₀₀. Differences in all nutrient harvest indices (NHI, PHI, and KHI) between I₁₀₀ and I75 were not significant. Furthermore, I75 statistically leveled with I₁₀₀ in nutrient partitioning indices, viz., NPI, PPI, and KPI. In conclusion, groundnut straw residues produced by 25% less water supply than normal may share in managing drought stress by releasing nutrients and saving irrigation water in arid areas.     

Nitrogen rate and cultivar effects on nitrogen and nitrate concentration of sweet potato leaf tissue

Abstract

Nitrogen applications to dallisgrass grown on Olivier silt loam, an Aquic Fragiudalf, increased forage yield, forage digestibility, nutrient concentrations and nutrient contents as N rates increased to 896 kg ha^‐1. Expressing yield as a function of N application rate resulted in quadratic prediction equations that accounted for 75 to 98% of the variability in yield during five years. Eighty‐six percent of the maximum yield was obtained during the five years at 448 kg of N ha^‐1. Plant concentrations of N, Ca and Mg were increased more than concentrations of the other macronutrients as N rates increased. Plant contents of N, Ca and Mg in the forage increased 4.0, 3.2 and 3.5‐fold as N rates increased to 448 kg ha^‐1, while that of P, K and S increased 2.5 to 2.8‐fold. Residual N accumulations in the soil profile were apparent at the 896 kg ha^‐1 rate at the end of the growing seasons but were not detected the following March, indicating N losses by leaching and/or denitrification occurred at that N rate. Phosphorus applications increased forage P concentrations but did not increase forage yield nor available P levels in the surface 15 cm of soil. Maximum yields were obtained at forage P concentrations and Bray No. 2 soil P levels as low as 2.0 g kg^‐1 and 17 mg kg^‐1, respectively.     

The effect of Ca and K levels on the herbage yield and nutrient composition of barley plants grown in high Mg soils

Abstract

The effects of Ca and K levels on barley (cv. Johnston) yield were studied in soil media containing high levels of Mg. The dry matter yield of barley decreased with increasing concentrations of Mg in soils, but the decrease was small. Dry matter yield was positively related to concentration of K in the soil. However, additions of fertilizer Ca or K did not increase dry matter yield, indicating that depressed yield associated with high Mg levels was not due to reduced availability of Ca or K. In commercial agriculture, applications of either Ca or K to such soils are unlikely to prove beneficial in increasing crop yields.

Concentrations of Mg in soil solutions of unfertilized soils were lower than levels which were previously shown to reduce crop yield. Additions of N fertilizer increased Mg concentrations to levels which could reduce barley yield     

The DRIS for interpretation of coastal bermudagrass analysis

Abstract

Diagnosis and Recommendation Integrated System (DRIS) norms for N, P, K, Ca, Mg, and S were developed for three high‐yield Coastal bennudagrass populations that were selected from soil fertility studies that contained six rates each of N, P, and K. Norms from the high‐yield population that was based on a single yield level at a given harvest date were considered most suitable. The relative importance of criteria used to select suitable diagnostic parameters was discussed along with composition of index equations. The norms developed from Coastal bennudagrass grown on an Aquic Fragiudalf soil in south Louisiana accurately predicted yield responses to N, P and K applications at that location and to P, S, and Mg applications on Typic Paleudult soils in north Louisiana. A computer generated DRIS balance chart was designed to provide a visual interpretation of individual sets of DRIS indices.     

Nitrogen effect on yield and kernel protein content of sweet corn grown on sandy soils

Abstract

Early spring application of N to Iowa sandy, leachable soils results in reduced sweet corn yields and kernel protein content. Normally, split N applications are used to coincide with crop N demand. Our objectives were to determine if nitrapyrin, a nitrification inhibitor, applied with urea would provide high yields and kernel protein levels when applied at planting.

Nitrogen rate increased yield, ear leaf N concentration, and kernel protein content in 1976 and 1978, with the optimum rate dependent on the year and soil N residual. Urea, with or without nitrapyrin, significantly enhanced yield 13%, early leaf N concentration 17%, and kernel protein content 9% as compared with Ca(NO₃)₂ for both years. High leaching loss of NO₃‐N occurred with the Ca(NO₃)₂ source as compared with urea alone. Kernel protein concentration correlated well with ear leaf N concentration (r = .74) and yield (r = .61). Ear leaf K content was not affected by N rate or source, but Ca(NO₃)₂ enhanced uptake of Ca and Mg as compared with the urea sources. Urea, with nitrapyrin, decreased leaf Mg content in 1978, but not in 1976, as compared with urea alone.     

Effect of fertilization and harvest frequency on yield and quality of tall fescue and smooth bromegrass

Abstract

Fertilization and harvest frequency affect yield and quality of forages. The purposes of this experiment were to determine (i) the effects of fertilization and frequent harvesting on yield and quality of tall fescue (Festuca arundinacea Schreb.) and smooth bromegrass (Bromus inermis Leyss.) and (ii) the efficiency of N in animal waste as compared with inorganic N fertilizer for forage production of these cool season grasses. ‘Fawn’ tall fescue and ‘Southland’ smooth bromegrass were grown in the greenhouse on Pullman clay loam topsoil (fine, mixed thermic Torrertic Paleustoll) under eleven fertilizer treatments and two harvest regimes. Nitrogen fertilizer increased yields, N and K concentrations and K/(Ca + Mg) ratios and decreased P, Ca, and Mg concentrations. Phosphorus and K fertilizers did not affect yields but applied P increased P and tended to decrease N and Ca concentrations. Applied K tended to increase Ca concentrations. Recovery of N from feedlot manure ranged from 0.8 to 14%, whereas, recovery from NH₄NO₃ averaged 64%. Harvesting at 3‐week rather than at 6‐week intervals reduced yields 25%; however, N and P removal were higher under the 3‐week harvest regime. Even though forage production was reduced under heavy utilization, the grasses required more N fertilizer under heavy than under lighter utilization. The two grasses produced similar yields under the 3‐week cutting regime and at N rates through 340 kg/ha under the 6‐week cutting regime. Tall fescue yields were higher with the higher N rates under the 6‐week cutting regime. Smooth bromegrass forage was higher than tall fescue forage in N, K, and Ca, whereas tall fescue forage was higher in P and Mg.