Organic Fertilizer Rates Research Articles

Pengurangan Dosis Pupuk pada Produksi Sawi Hijau Organik dengan Pergiliran Tanaman Jagung dan Kedelai

<p> The application of organic fertilizer and crop rotation are combination of cultivation system integrally to preserve land fertility. This study aimed to determine the effect of crop residues produced in the first season to reduce organic fertilizer rate for mustard greens cultivation in the second season. The experiment was conducted at IPB organic farm, Cikarawang, Darmaga in April until June 2015. The first season was the first experiment conducted separately for soybean and corn to study different manure types for both crops which the rate of each manure was 20 ton ha-1 for soybean and 25 ton ha-1 for corn. Soybean and corn residues were used in the following season on mustard green cultivation. The experimental design was split plot design with crop residues as main plot, and combination of manure types (chicken, cow, goat) and rates (0, 10 ton ha-1) as sub plot. Data were analyzed using variance. Means were statistically compared with Tukey test at α < 0.05 level. The results showed that the soybean and corn residues can be used as nutrient sources for mustard greens cultivation. The application of manure was not necessary for mustard greens cultivation if soybean or corn residues were added in the second season and there was residues from manure in the first season.<br /><br />Keywords: chicken manure, cow manure, crop residue, goat manure <br /><br /><br /></p>

Soil chemical properties and growth response of Moringa oleifera to different sources and rates of organic and NPK fertilizers

PurposeThe need for increasing production of Moringa oleifera in Nigeria can be achieved through adequate fertilization. This study investigated the effects of sources and rates of NPK (15:15:15) and compost on soil properties and productivity of Moringa at National Horticultural Research Institute, Ibadan, Nigeria.MethodsNPK was applied at 30, 60, and 90 kg N/ ha, cow dung (CD), poultry manure (PM) and organomineral (OM) were applied at 10, 20 and 30 tons/ha. The experimental design was a randomized complete block design with three replicates. Organic fertilizers were incorporated into the soil 2 weeks before sowing; NPK was split applied at 2 and 5 weeks after sowing. Seeds were sown at 75 cm × 75 cm spacing. Data were taken on plant height (cm), stem girth (cm), number of leaves, leaf biomass, stems weight and post-planting soil properties.ResultsGrowth values for NPK and compost treatments were higher than the control. PM applied at 30 tons ha−1 resulted in highest growth values: plant height (65.91 cm), stem girth (1.51 cm) and number of leaves (14.20). PM applied at 30 tons ha−1 gave higher stem weight (2249.9 g) and leaf biomass (3610.5 g). Post-planting soil analysis indicated that nitrogen, phosphorus, calcium, sodium, manganese, iron and zinc contents were higher in plots with organic and inorganic fertilizers except for potassium and magnesium.ConclusionPM proved more superior to CD manure and others because it produced better growth attributes such as shoot height, stem girth and number of leaves and leaf biomass than its counterparts produced.

Optimal Rate of Organic Fertilizer during the Vegetative-stage for Cannabis Grown in Two Coir-based Substrates

Cannabis producers, especially those with organic operations, lack reliable information on the fertilization requirements for their crops. To determine the optimal organic fertilizer rate for vegetative-stage cannabis (Cannabis sativa L.), five rates that supplied 117, 234, 351, 468, and 585 mg N/L of a liquid organic fertilizer (4.0N–1.3P–1.7K) were applied to container-grown plants with one of two coir-based organic substrates. The trial was conducted in a walk-in growth chamber and the two substrates used were ABcann UNIMIX 1-HP with lower water-holding capacity (WHC) and ABcann UNIMIX 1 with higher WHC. No differences in growth or floral dry weight (yield) were found between the two substrates. Pooled data from both substrates showed that the highest yield was achieved at a rate that supplied 389 mg N/L (interpolated from yield-fertilizer responses) which was 1.8 times higher than that of the lowest fertilizer rate. The concentration of ∆9-tetrahydrocannabinol (THC) in dry floral material was maximized at a rate that supplied 418 mg N/L, and no fertilizer rate effects were observed on Δ9-tetrahydrocannabidiolic acid (THCA) or cannabinol (CBN). The highest yield, cannabinoid content, and plant growth were achieved around an organic fertilizer rate that supplied 389 mg N/L during the vegetative growth stage when using the two coir-based organic substrates.

Response of parsley (Petroselinum crispum) to different application rates of organic fertilizer

Response of parsley (Petroselinum crispum) to different application rates of organic fertilizer

Field performance of spider plant (Cleome gynandra L) under different agronomic practices

Field experiments were carried out at Kaguvi Vocational Training Centre located in the Midlands province of Zimbabwe, to determine the effect of planting date and fertilizer types in enhancing the productivity of spider plant, an indigenous leafy vegetable. The experimental design was a split- plot arranged in a randomized complete block design (RCBD) with three blocks. The planting date was the main plot with three levels (15/10/12, 30/01/13 and 15/02/13) and the fertilizer treatments as the subplots with seven levels including a control (no fertilizer applied), 20 t/ha cattle manure, 30 t/ha cattle manure, 5 t/ha poultry manure, 10 t/ha poultry manure, 300 kg/ha Compound D + 100 kg/ha ammonium nitrate and 300 kg/ha Compound D + 150 kg/ha ammonium nitrate). Growth parameters, vitamin A and C, crude protein, iron content, fresh and dry yield were significantly (p<0.05) increased by use of organic and inorganic fertilizers across all planting dates compared to the control where no fertilizers were added. The October 2012 planting date, combined with high rates of organic and inorganic fertilizers had the best response with regards to the variables measured, including the duration of the harvest period which was nine weeks, compared to the January and February planting dates where harvesting was for six weeks. The inorganic fertilizers provided readily available nutrients for uptake by the plants while the long production period for the October 2012 planting date enabled the organic manures (cattle and poultry manure) adequate time to release the nutrients for uptake, compared to the January 2013 and February 2013 planting dates. It can be concluded that there is merit in staggering the planting dates while using organic and inorganic fertilizers as the practice results in an extended harvest period. High rates of both inorganic and organic fertilizers are recommended for the different planting dates as follows; 30 t/ha cattle manure, 10 t/ha poultry manure, 300 kg/ha Compound D + 100 kg/ha ammonium nitrate and 300 kg/ha Compound D + 150 kg/ha ammonium nitrate. Key words : Indigenous vegetable, spider plant, planting dates, fertilizers, nutrients

The Effect of Organic and Inorganic Fertilizers on the Yield of Two Contrasting Soybean Varieties and Residual Nutrient Effects on a Subsequent Finger Millet Crop

The problems of low soil fertility resulting from continuous monocropping, crop residue removal and limited fertilizer use represent key challenges to produce surplus food for the ever increasing population of Ethiopia. However, the practices of crop rotation and integrated sources of fertilizer uses could potentially improve soil fertility and productivity. In 2012 and 2014, soybean with different trials consisting of two soybean varieties (Boshe and Ethio-ugozilavia), three levels of farm yard manure (FYM) (3, 6 and 9 t/ha) and three phosphorus levels (8, 16 and 24 kg P ha−1) were combinedin2×3×3factorialarrangements. Twosoybeanvarietiesreceivingnofertilizerapplication followed by finger millet receiving a recommended rate (20 kg P/ha) were included. The experiment was laid out in a randomized complete block design with three replications. In 2013 and 2015, finger millet was planted on each soybean plot as per previous treatment arrangements to evaluate the effect of the precursor crop (soybean) and integrated fertilizer application on yield performance of the subsequent finger millet. Soil pH, organic carbon, total nitrogen and available phosphorus before planting and after crop harvest of soybean in each year showed treatment differences. Both precursor crop and fertilizer application had a positive effect on soil fertility status and, hence, improved the performance of the subsequent finger millet. On the other hand, since the rainfall amount and distribution were different in the 2012 and 2014 seasons, the response of soybean varieties to applied fertilizers was significantly affected, and the correlation between soybean yield and annual rainfall was strongly positive. Use of an early maturing soybean variety (Boshe) with the lowest rates of organicandinorganicfertilizersgavesignificantlyhigheryieldin2012(shortrainyseason)compared with other treatment combinations. In the 2014 cropping season, however, ‘Ethio-ugozilavia’ showed greateryield performancewith the combinedapplication of3 t FYM/haand 1616kg PP/ha followed by 3 t FYM and 88 kg P/ha. Hence, it is recommended to use the ‘Boshe’ variety under a short rainy season and under a low soil fertility status, while variety the ‘Ethio-ugozilavia’ can be used under goodrainyandsoilfertilitymanagementconditions. Consideringresidualeffects,theuseoftheearly maturing soybean variety as a precursor with 3 t FYM/ha and 8–16,816 kg P/ha during the short rainy season could enhance the yield of the subsequent finger millet. On the other hand, the use of the late maturing soybean variety as a precursor with higher organic fertilizer rates (6–9 t FYM/ha) resulted in a significant yield increase of the subsequent finger millet. The use of a late maturing variety of soybean with lower rates of organic manure resulted in a finger millet yield comparable to farmers’ practice, indicating that this option can be adopted by smallholder farmers who cannot produce sufficient organic manure. This study showed that planting of finger millet after a soybean precursor crop even without fertilizer application could give better yield and economic benefits as it saves 70–85% of chemical fertilizer costs compared to the farmers’ practice.

Integrated Fertilizer Management: Influence on Soil Nitrogen, Available Phosphorus, Potassium, Nutrient Uptake and Maize Yield

ABSTRACTA field experiment was conducted on an Alfisol (kandic paleustalf) in Abeokuta, Southwestern Nigeria, for two seasons to assess the influence of inorganic and organic fertilizers on nitrogen (N), phosphorus (P), potassium (K), nutrient uptake and maize yield. The treatments consisted of three rates of organic fertilizer 0, 5 and 10 t ha−1 in the form of poultry manure and NPK fertilizer (20:10:10) applied at 0 and 120 kg ha−1. Maize (Zea mays) was used as the test crop. The results showed that the combined application of 10 t ha−1 poultry manure and 120 kg ha−1 NPK fertilizer enhanced the uptake of N, P and K better than other treatment combinations. Application of 10 t ha−1 poultry manure alone gave the highest grain yield, which was 67.02% higher than the control in the first season. Complementary application of 5 t ha−1 poultry manure with 120 kg ha−1 NPK 20–10-10 was recommended for grain yield.

Effect of integrated use of manure and fertilizer on the growth and yield of potato

An experiment was set up in the Research Farm of Patuakhali Science and Technology University, during the rabi season of 2015 to evaluate the effect of fertilizers and manures on the growth and yield of Potato. The experiment was laid out in a Randomized Complete Block Design (RCBD) with two potato varieties namely Diamant (V1) and Cardinal (V2) and five different types and rates of organic manures and inorganic fertilizers viz. T0: Control , T1: NPK, T2: NPK + CW(Cowdung), T3: NPK+ PM(Poultry Mannure) and T4: CW(Cowdung), + PM(Poultry Mannure) were used for the present study. The two–factor experiment was laid out in a Randomized Complete Block Design (RCBD) with three replications. Result showed that almost all the characters were affected significantly due to the effect of varieties, organic–inorganic fertilizer and their combinations .In case of treatments, NPK with PM also showed the tallest plant (39.76 cm), highest fresh and dry weight (95.97 and 6.05 g plant–1, respectively), CGR and RGR (0.086 and 0.218 g m–2 day–1, respectively), gross (24.36 t ha–1) and marketable (23.39 t ha–1) compared other treatments. In case of interaction, the highest plant height (41.00 cm), highst fresh and dry weight (96.87 and 3.62 g plant–1, respectively), highest CGR and RGR (0.089 and 0.228 g m–2 day–1, respectively) as well as the highest gross (24.45 t ha–1) and marketable (23.67 t ha–1) yield were recorded in Diamant at NPK with PM. From the above observation it may be concluded that the variety Diamant at NPK + PM was more effective under Patuakhali region.Progressive Agriculture 27 (4): 435-443, 2016

Phosphorus speciation and transformation in long-term fertilized soil: evidence from chemical fractionation and P K-edge XANES spectroscopy

Knowledge of speciation and transformation of phosphorus (P) in soil following high application rates of chemical and organic fertilizers is essential for improving P management in Chinese agricultural ecosystems because P fertilizers have been increasingly overapplied in China. Phosphorus speciation of the soil in three long-term fertilization experiments established in 1990 was investigated jointly with a sequential fractionation scheme and P K-edge X-ray absorption near edge structure (XANES) spectroscopy. Both chemical fractionation and XANES spectroscopy confirmed that P species in the topsoils (0–20 cm) were mainly composed of iron phosphate, calcium phosphate and organic P, regardless of soil pH and mineralogy. The continuous application of nitrogen, phosphorus and potassium fertilizers (NPK) had little effect on the distribution of P species in the topsoils compared with that in the control and 1990 baseline topsoils. In contrast, the application of NPK plus organic manures (MNPK) changed significantly the speciation distribution of P by increasing distinctly available P in the soil. The transportation and transformation of P species depended on soil properties including P levels, organic carbon concentrations and mineral types. The long-term application of MNPK facilitated the transportation of P into lower horizons and the accumulation of organic P in the soil. The XANES results provided spectroscopic support for the P species identified by the fractionation scheme, and the combination of the two techniques provided complementary information on the speciation and transformation of P in soil.

Balanced Fertilization and Rate of Organic Foliar Fertilizer on the Yield and Biomass of Sweet Corn

This study was conducted to determine the yield and biomass of sweet corn (Zea mays) applied with balanced fertilization and organic fertilizer. The field trials was laid out in RCBD factorial design with 5 treatments and 3 replications. The findings revealed that balanced fertilization plus 75% to 125% of vermicast significantly higher on yield but insignificantly different with biomass. The return of investment showed insignificant difference on both treatments. However, the highest percentage of the highest return of investment is the balanced fertilization strategy plus compost based on the recommended rate of Bureau of Soils and Water Management. Balanced fertilization plus rate of vermicast of 100-125% gave the best and significant performance in sweet corn yield. Through chemical analyses, Vermicast fertilizer have a composition of 2%Nitrogen, 12%P2O5, 2%K2O, 6%Calcium, 9%Magnesium, 0.45%Zinc, 2.5%Sulfur, 0.2%Manganese, 5%Iron, 0.2%Copper, 0.1% Boron, 1%Molybdenum, 1% Chloride, and about 29% organic matter that promotes best growth in Zea mays. Thus, it is concluded that balanced fertilization plus vermicast with a rate of 100-125% is the best fertilization strategy to increase the yield of sweet corn of about 25% as compared to balanced fertilization alone.

EFFECTS OF DIFFERENT RATES OF ORGANIC AND INORGANINC FERTILIZER ON GROWTH AND YIELD COMPONENTS OF POTATO (SOLANUM TUBEROSUM L.) IN JIMMA ARE, SOUTH WEST ETHIOPIA

The experiment was conducted under field condition at Jimma University College of Agricultures and Veterinary Medicine (JUCAVM) to determine the Effects of Different Rate of Organic and Inorganic Fertilizer on Growth and yield Components of Potato (Solanum tuberosumL).The experiment design used was randomized complete block design(RCBD). The experimental treatments were replicated three times. A Potato cultivar ‘Jalene’ was grown combined with Farmyard manure and nitrogen (F0N0), (F20N70), (F0N35),(F0N70), (F20N35), (F20N0) as a treatment.. Data were recorded on Potato leaf area, plant height, leaf length, leaf number, leaf diameter, stem diameter and stem number. The result revealed that the combination of various level of Farmyard manure and nitrogen statistically (p≤0.05) affected leaf area, plant height, leaf length, leaf number, leaf diameter, stem diameter and stem number. The maximum values for leaf area, plant height, leaf length, leaf number, leaf diameter, stem diameter and stem number were recorded from (F0N70, F20N70, F0N70, F20N35, F20N0, F20N70, F20N0) respectively .However The minimum values of all the parameters were recorded from the control treatment (F0 N0). From the study it could be concluded that Potato yield components were greatly affected by different rates of organic and inorganic fertilizers. The appropriate amount of different rates of fertilizers (farmyard manure and nitrogen) should be used to increase Potato growth and yield.

EFFECT OF GREENHOUSE NIGHT HEATING BY SOLAR ENERGY SYSTEM AND ORGANIC FERTILIZER ON THE PRODUCTIVITY OF TOMATO

The aim of this experimental work was to investigate the effect of utilizing different rates of dried biogas digester residue as organic fertilizer and solar energy for heating greenhouse on growth, development, productivity, and fruit quality of tomato hybrid (Agiad 7) during winter of two following growing seasons (2013 and 2014). Two similar gable-even-span greenhouses were functioned at EL-Sabahia Horticultural Research Station. The seedlings of tomato hybrid Agiad 7 were planted on the 1st week of December during the two growing seasons under two different greenhouse microclimates. The first greenhouse (GH1) was equipped with a complete heating system utilizing the solar energy, while, the second greenhouse (GH2) was mechanically ventilated during daylight without heating system. Referring to the effect of the solar heating system on the greenhouse microclimate, the obtained results revealed that, the maximum and minimum indoor air temperatures of greenhouse (GH1) were (24.3 and 11.6), (26.0 and 12.1), (28.1 and 15.2), (28.6 and 16.3) and (30.6 and 17.1) oC during the experimental period (from December to April), respectively. On the other hand, the maximum and minimum indoor air temperatures of the greenhouse (GH2) were (25.3 and 6.0), (26.8 and 6.3), (28.0 and 10.8), (29.8 and 13.4) and (32.6 and 15.3) oC during the same period, respectively. Referring to the effect of organic fertilizer rates on the tomato plant vegetative growth, showed that increasing the organic fertilizer rate significantly increased all the studied characters; plant length, leaf area, number of leaves per plant, dry weight and stem diameter in both seasons whereas, the fresh weight increase was not significant in 2014 season. The data also, showed that plants fertilized with 30 m3/fed from dried biogas residue gave the best vegetative growth characteristics; plant height, leaf area, fresh, dry weight per plant and stem diameter as compared with other used organic levels in both seasons. Early yield, number of fruit per plant, fruit weight, total yield per plant and total yield per feddan were significantly increased by increasing the organic fertilizer rate in both 2013 and 2014 seasons. For the heated greenhouse (GH1), the percentages increase in early yield, number of fruit per plant, fruit weight, total yield per plant and total yield per feddan were 28.64, 13.04, 6.89, 20.84 and 20.84%, respectively for dried biogas residue of 30 m3/fed over those of farm yard manure, respectively in 2013 season. For the unheated greenhouse (GH2), the percentages increase in early yield, number of fruit per plant, fruit weight, total yield per plant and total yield per feddan over those of farm yard manure were 13.18, 16.29, 8.30, 25.52 and 25.52%, respectively for 30 m3/fed dried biogas residues in same season. Whereas, in the second season 2014, for the heated greenhouse (GH1), the percentages increase in early yield, number of fruit per plant, fruit weight, total yield per plant and total yield per feddan over those of farm yard manure were 24.87, 11.18, 6.89, 18.86 and 18.86%, respectively for 30 m3/fed dried biogas residue, respectively. For the unheated greenhouse (GH2), the percentages increase in early yield, number of fruit per plant, fruit weight, total yield per plant and total yield per feddan over those of farm yard manure were 17.18, 16.29, 5.87, 22.84 and 22.84%, respectively for 30 m3/fed dried biogas residues in same season. Concerning effect of the microclimatic conditions of (GH1) it was at and around the optimal level for the tomato crop, resulting in increase the tomato growth, development, and productivity. The percentages increase for greenhouse GH1 over GH2 greenhouse in early yield, number of fruit per plant, fruit weight, total yield per plant and total yield per feddan were 21.32, 17.42, 12.87, 32.28 and 32.28%, respectively, in 2013 season while, they were 16.06, 15.33, 10.14, 27.08 and 27.08%, respectively in 2014 season.

Response of wheat 'Triticumaestivum L.' to humic acid and organic fertilizer application under varying Siwa Oasis conditions

A field experiment was carried out at Siwa Oasis, Matrouh governorate, during 2012/2013 growing winter season, to study the response of wheat (Triticumaestivum, L.) cv. Sakha 94, to applications of humic acid rates (8.3, 10.7 and 13.1 kg/ha) and organic fertilizer rates (35, 47.5 and 60 m 3 /ha) under varying Siwa conditions. The most important results are summarized as follows:1) Variation in soil salinity had an impact on studied characters, especially those subjected to combined analysis over locations. 2) Spike length, no. of spikelet/spike and 1000-grain weight were increased with increasing both organic and humic acid rates in the three locations. 3) The data for combined analysis showed significant differences between locations, organic fertilizer rates and applied humic acid rates for plant height, no. of spikes/m 2 , no. of grains/spike, biological yield and harvest index. 4) Location 2, with lowest E.C. values gave significantly higher values for plant height, biological yield, grain yield and yield components, i.e. number of spikes/m 2 and number of grains/spike, and harvest index compared to location 1 and 3. 5) Increase in grain yield reached 7.1 and 13.6 % by increasing humic acid rate from 8.3 to 10.7, and from 8.3 to 13.1, respectively.

Effect of Fertilizer Management in Combination with Soil Conditioner on Yield of Cassava Cultivated on Coarse-Textured Soil in Thailand

This study was conducted to determine the effect of fertilizer management in combination with soil conditioner (zeolite, pumice and organic fertilizer) on yield of cassava var. Huay Bong 60 cultivated on coarse-textured soil in Thailand. The experiment was arranged in a randomized complete block design. The results revealed that addition of chemical fertilizer combined with organic fertilizer rate 1,018.75 kg ha-1 gave the highest plant height, above ground biomass, fresh tuber yield, starch content, starch yield and concentration of primary nutrient in fresh tuber yield and were not difference from addition of 100% chemical fertilizer combined with zeolite rate 312.5 kg ha-1 (P≤0.01). After experiment, it was found that all treatments comprising sole chemical fertilizer at various rates or combined with soil conditioners were found to influence soil properties; soil pH was moderately to slightly acid, electrical conductivity (ECe) was non-saline soil, low to moderately low organic matter in soil, moderately low to moderate cation exchange capacity (CEC), low to moderate available P in soil; very low exchangeable K in soil.

CHAMOMILE PRODUCTION USING SUPPLEMENTARY IRRIGATION AND ORGANIC FERTILIZATION IN SANDY SOILS

ABSTRACT: The use of medicinal plants in the herbal medicine of Brazilian Health System has intensified production and the need for developing efficient agricultural techniques that promote greater productivity of these species. The objective of this work was to evaluate the chamomile production at field conditions as a function of irrigation depths and organic fertilizer rates. The experiment was conducted in the Universidade do Oeste Paulista (Campus II experimental area), in Presidente Prudente, São Paulo State, Brazil. A triple factorial experimental design was used, consisting of irrigation rates (150, 100, 75, 50, 25 and 0% of the reference evapotranspiration - ETo), organic manure types (poultry and cattle manure) and manure rates (0, 3 and 5 kg m-2), with four replications. The capitula production per plant, capitula dry weight and yield per water input (water use efficiency) were evaluated. The supplementary irrigation combined with organic manure fertilization provided the highest capitula yield for chamomile crop in the Presidente Prudente region. The combination of poultry manure at rate of 5 kg m-2 with water depth equal to 150% of the ETo resulted in higher average values of capitula fresh and dry weight and water use efficiency.

Nitrogen Fertilization Strategies for Organic Wheat Production: Crop Yield and Nitrate Leaching

Nitrogen fertility management represents a crucial aspect for common wheat (Triticum aestivum L.) production, particularly when we deal with organic agriculture. This study was conducted to determine the effect of five N fertilization strategies on yield, grain protein content, and N leaching risk. In a 3‐yr field experiment, a faba bean/wheat temporary intercropping (TIC) and four fertilization treatments with extra‐farm N sources were compared. Extra‐farm N sources were represented by blood meal (BM) and roasted leather (RL) (broadcast all‐at‐once at seeding or split into one‐half at seeding and one‐half at tillering in a side‐dressing application). Unfertilized and mineral fertilized controls were included. The effect of the legume on TIC wheat N uptake was always positive while dry weight accumulation and yield were generally poorly affected. Regardless of the broadcasting method, BM treatments generally showed a slightly higher yield and grain protein content compared to wheat fertilized with roasted leather (this was also confirmed by fertilizer release efficiency). The risk of N leaching was maximum at the onset of drainage (i.e., during the first phase of crop growth), so using organic fertilizers at pre‐seeding stage appeared to be a very risky practice, especially if quick‐N‐releasing ones are used. Splitting the organic fertilizer rate avoided a large amount of mineralized N to be leached in the watershed during the critical stage of drainage onset. The TIC was the best option in terms of environmental preservation, and assured a constantly higher grain protein content compared to the other organic fertilization treatments.

Selected Macronutrient Uptake by Sweet Corn under Different Rates of Liquid Organic Fertilizer in Closed Agriculture System

In the last few years, soil deterioration due to excessive application of synthetic agrochemical has become growing concern. Use of organic fertilizer is believed to be able to enhance soil quality. The objective of this experiment was to determine nitrogen, phosphorus, and potassium uptakes by sweet corn as affected by local based liquid organic fertilizer (LOF) under closed agriculture system. The experiment was conducted in Closed Agriculture Production System (CAPS) Research Station in Air Duku Village, Bengkulu, Indonesia from March to June 2015, employing Randomized Completely Block Design with 2 factors. The first factor was 3 sweet corn genotypes, i.e. Talenta, Jambore, and Asian Honey and the second factor was 5 rates of LOF, i.e. 0, 25, 50, 75, and 100 mg l-1, respectively. Each treatment combination was replicated 3 times. Foliar application of LOF was carried out every week at 2-8 weeks after planting (WAP) with total volume of 600 ml per plant. Sweet corn leaves were sampled at the beginning of tassel emergence. The experiment revealed that sweet corn genotype significantly influenced the uptake of nitrogen, but not phosphorus and potassium. It was observed that Asian Honey genotype absorbed highest nitrogen as compared to other genotypes. In addition, increase in rates of LOF significantly raised nitrogen uptake by sweet corn, but not phosphorus and potassium.

Use of compost as an alternative to conventional inorganic fertilizers in intensive lettuce (Lactuca sativa L.) crops—Effects on soil and plant

Intensive crop over-fertilization is causing the diffuse contamination of superficial and ground-waters by nitrates in many Mediterranean areas. At the same time this practice is also damaging the soil in the long-term. In this work the feasibility of using composts as total or partial substitutes for conventional inorganic fertilization (CIF) was evaluated in two successive crops of lettuce (Lactuca sativa L.), one of the most consumed vegetables in Europe. The aim was to offer alternative agricultural practices that are more environmentally friendly. Treatments consisting of various rates of inorganic and organic fertilizers (composts) were assayed in quadruplicate on a sandy loam soil classified as Haplic Calcisol in Southern Spain. Macro- and micronutrients and heavy metal concentrations were analysed in soil and plant leaves. Parameters such as soil basal respiration (BR), microbial biomass C (Cmic) and dehydrogenase (DHA) and hydrolase activities, indicators of soil microbial abundance and activity, were also determined after each crop. After the second lettuce crop, certain physical soil properties such as aggregate stability and soil water holding capacity were also determined. In the first crop lettuce yields in the compost-treated soils did not significantly (p≤ 0.05) differ from the yields of CIF-treated soils. In the second crop, however, lettuce yields were higher in organically treated soils than in soils receiving only inorganic fertilization. Organic fertilizers were able to supply sufficient nutrients to achieve similar yields as those obtained with additional inorganic fertilizer. After the second crop, organically treated soils also showed higher C, N, P concentrations and higher Cmic, BR and DHA than soils receiving conventional inorganic fertilization as well as improved physical conditions (a higher percentage of stable soil aggregates and a greater water holding capacity). Also after the second lettuce crop, compost-treated soils showed significantly higher β-glucosidase and phosphatase activity than CIF-treated soils. Furthermore, lettuces grown in compost-treated soils showed significantly lower leaf nitrate concentration than lettuces grown in soil receiving CIF, thus reducing the potential toxicological risks associated with consuming nitrate-rich foods. Moreover, compost fertilization did not increase the concentration of heavy metals in lettuce leaves. Results confirm that manure and sewage sludge composts can be used as an alternative to inorganic fertilization in lettuce crop cultivation, leading to similar or even higher yields and reducing nutrient-leaching risks, while improving soil chemical, physical and microbiological properties.

Temporal Profiles of Soil Properties and Performance of Amaranthus Grown on Farm Yard Manure-mediated Crude Oil Polluted Soil

An experiment was conducted in the plant house of the Department of Crop, Soil and Pest management, Federal University of Technology, Akure, Nigeria, to examine the efficacy of manuring and incubation periods on the amelioration of the toxic effects of crude oil contamination on soil properties and Amaranthus performance. The time dynamics of physical, chemical and microbial population of the manured mediated crude oil contamination were observed following 270 days (9 months) of incubation. Bonny light crude oil was applied at zero and 5% (0 and 325 ml per pot) to the containerized (pot) soil which were amended with Farm Yard Manure (FYM) at 0 and 40 g per pot. The manure-mediated crude oil polluted containerized soil were incubated for periods of 0, 2, 4, 6 and 9 months. Treatments were arranged using Completely Randomised Design (CRD) with three replications. The toxicity of the crude oil pollution and its capacity to support plant growth was assessed via germination, seedling survival and growth of Amaranthus at the various periods of incubation. Data were also collected on soil biological, physical and chemical properties at the various sampling dates (periods of incubation). Application of organic fertilizer to crude oil-contaminated soil produced significant influence on soil chemical properties, microflora populations, and on the growth characters of Amaranthus. Organic amendment of crude oil contamination at two rates of organic fertilizer produced increases in soil pH and its contents of organic matter, N, P and K, and the colony sizes of microflora populations, and improved root, shoot biomass and leaf development of Amaranthus. Soil application of of crude oil affected soil chemical properties via decreases in soil pH, organic matter, N, P and K) and the colony sizes of microflora populations (bacterium, yeast and fungi counts). Crude oil contamination inhibited seed germination and growth of Amaranthus from the commencement of experiment to 4 weeks after treatment application. The time changes in soil elemental concentrations and biological populations following contamination with crude oil was monitored. Data obtained on soil chemical constituents (pH, organic matter, CEC) biological populations were fitted to correlation and regression models. The observed trendlines in time-dependent elemental concentration and soil biological populations were described by power, logarithmic and polynomial relations with high R2values. The initial declining trends in values with time up to the forth months after crude oil application were followed by a little linear increases in soil chemical properties and microbial population with time. These trends were consistent for both soil chemical properties and microbial population. The nature of the trends (polynomial function as best fit) indicate that the responses were not sole function of a factor but suggest synergy among factors responsible for the decay of petroleum hydrocarbon compounds and hence its toxicity to soil chemical properties and biological activities. The study showed that soil microbiological population (diversity) may be useful tools for assessing the effect of petroleum hydrocarbon contamination on soil and environmental health.

Organic and Nitrogen Fertilization of Soil under ‘Syrah’ Grapevine: Effects on Soil Chemical Properties and Nitrate Concentration

Viticulture is an activity of great social and economic importance in the lower-middle region of the Sao Francisco River valley in northeastern Brazil. In this region, the fertility of soils under vineyards is generally poor. To assess the effects of organic and nitrogen fertilization on chemical properties and nitrate concentrations in an Argissolo Vermelho-Amarelo (Typic Plinthustalf), a field experiment was carried out in Petrolina, Pernambuco, on Syrah grapevines. Treatments consisted of two rates of organic fertilizer (0 and 30 m3 ha-1) and five N rates (0, 10, 20, 40, and 80 kg ha-1), in a randomized block design arranged in split plots, with five replications. The organic fertilizer levels represented the main plots and the N levels, the subplots. The source of N was urea and the source of organic fertilizer was goat manure. Irrigation was applied through a drip system and N by fertigation. At the end of the third growing season, soil chemical properties were determined and nitrate concentration in the soil solution (extracted by porous cups) was determined. Organic fertilization increased organic matter, pH, EC, P, K, Ca, Mg, Mn, sum of bases, base saturation, and CEC, but decreased exchangeable Cu concentration in the soil by complexation of Cu in the organic matter. Organic fertilization raised the nitrate concentration in the 0.20-0.40 m soil layer, making it leachable. Nitrate concentration in the soil increased as N rates increased, up to more than 300 mg kg-1 in soil and nearly 800 mg L-1 in the soil solution, becoming prone to leaching losses.