Slow-release and organic fertilizers on early growth of Rangpur lime

Slow-release and organic fertilizers are promising alternatives to conventional fertilizers, as both reduce losses by leaching, volatilization and problems of toxicity and/or salinity to plants. The objective of this work was to evaluate the effect of different rates of the organic fertilizer Humato-Macota® compared with the slow-release fertilizer Osmocote® on the growth and nitrogen content in the dry matter of Rangpur lime. A field experiment was conducted in a factorial completely randomized design with an additional treatment (4 x 4 +1). The first factor consisted of four Humato­Macota® rates (0, 1, 2, and 3%) applied to the substrate; the second factor consisted of the same Humato-Macota® concentrations, but applied as fortnightly foliar sprays; the additional treatment consisted of application of 5 kgm-3 Osmocote® 18-05-09. Means of all growth characteristics (plant height, total dry matter, root/shoot ratio and leaf area) and the potential quantum yield of photosystem II (Fv/Fm) were higher when plants were fertilized with the slow-release fertilizer. The organic fertilizer applied alone did not meet the N requirement of Rangpur lime.

Orchid growth and nutrition in response to mineral and organic fertilizers

Orchid fertilization is fundamental for a satisfactory plant growth and development for commercial orchid production as well as in collections. Mineral and/or organic sources can be used for fertilization. The objective of this study was to evaluate the effect of the use of organic and/or mineral fertilizers on the nutrition and growth of orchid (Laelia purpurata 'werkhanserii' x L. lobata 'Jeni') seedlings in greenhouse. The following fertilizers were tested: an NPK fertilizer + micronutrients; a Ca source in the form of calcium nitrate; two organic fertilizers, one prepared with a mixture of bone meal, castor meal and ash, and a similar commercial fertilizer. The organic fertilizers were distributed on the surface of the pots every two months and the minerals were applied weekly to the substrate in 25 mL aliquots of a solution containing 1 g L-1 of the respective fertilizer. The plant response to the application of mineral together with organic fertilizer was better, with higher dry matter production than by the isolated application of each fertilizer (organic or mineral). The treatments with calcium nitrate + NPK fertilizer did not differ significantly from the use of NPK fertilizer, probably due to the S deficiency detected in a mineral analysis of the tissues. Commercial organic fertilizer had a very elevated B level, leading to toxicity symptoms, reduced growth and necrotized tips of the older leaves in all fertilized treatments.

SOIL CHEMICAL PROPERTIES AND GROWTH OF SUNFLOWER (HELIANTHUS ANNUUS L.) AS AFFECTED BY THE APPLICATION OF ORGANIC FERTILIZERS AND INOCULATION WITH ARBUSCULAR MYCORRHIZAL FUNGI

The use of organic fertilizers and the inoculation of mycorrhizal fungi in the cultivation of oil crops is essential to reduce production costs and minimize negative impacts on natural resources. A field experiment was conducted in an Argissolo Amarelo (Ultisol) with the aim of evaluating the effects of fertilizer application and inoculation of arbuscular mycorrhizal fungi on the growth attributes of sunflower (Helianthus annuus L.) and on soil chemical properties. The experiment was conducted at the Federal University of Rio Grande do Norte, Brazil, using a randomized block design with three replicates in a 4 × 2 factorial arrangement consisting of four treatments in regard to application of organic fertilizer (liquid biofertilizer, cow urine, mineral fertilizer, and unfertilized control) and two treatments in regard to arbuscular mycorrhizal fungi (with and without mycorrhizal fungi). The results showed that the physiological attributes of relative growth rate and leaf weight ratio were positively influenced by fertilization, compared to the control treatment, likely brought about by the supply of nutrients from the fertilizers applied. The growth and productivity attributes were positively affected by mycorrhization.

The potential of organic fertilizers and water management to reduce N2O emissions in Mediterranean climate cropping systems. A review.

Environmental problems related to the use of synthetic fertilizers and to organic waste management have led to increased interest in the use of organic materials as an alternative source of nutrients for crops, but this is also associated with N2O emissions. There has been an increasing amount of research into the effects of using different types of fertilization on N2O emissions under Mediterranean climatic conditions, but the findings have sometimes been rather contradictory. Available information also suggests that water management could exert a high influence on N2O emissions. In this context, we have reviewed the current scientific knowledge, including an analysis of the effect of fertilizer type and water management on direct N2O emissions. A meta-analysis of compliant reviewed experiments revealed significantly lower N2O emissions for organic as opposed to synthetic fertilizers (23% reduction). When organic materials were segregated in solid and liquid, only solid organic fertilizer emissions were significantly lower than those of synthetic fertilizers (28% reduction in cumulative emissions). The EF is similar to the IPCC factor in conventionally irrigated systems (0.98% N2O-N N applied−1), but one order of magnitude lower in rainfed systems (0.08%). Drip irrigation produces intermediate emission levels (0.66%). Differences are driven by Mediterranean agro-climatic characteristics, which include low soil organic matter (SOM) content and a distinctive rainfall and temperature pattern. Interactions between environmental and management factors and the microbial processes involved in N2O emissions are discussed in detail. Indirect emissions have not been fully accounted for, but when organic fertilizers are applied at similar N rates to synthetic fertilizers, they generally make smaller contributions to the leached NO3− pool. The most promising practices for reducing N2O through organic fertilization include: (i) minimizing water applications; (ii) minimizing bare soil; (iii) improving waste management; and (iv) tightening N cycling through N immobilization. The mitigation potential may be limited by: (i) residual effect; (ii) the long-term effects of fertilizers on SOM; (iii) lower yield-scaled performance; and (iv) total N availability from organic sources. Knowledge gaps identified in the review included: (i) insufficient sampling periods; (ii) high background emissions; (iii) the need to provide N2O EF and yield-scaled EF; (iv) the need for more research on specific cropping systems; and (v) the need for full GHG balances. In conclusion, the available information suggests a potential of organic fertilizers and water-saving practices to mitigate N2O emissions under Mediterranean climatic conditions, although further research is needed before it can be regarded as fully proven, understood and developed.

Carbon dioxide emissions from semi-arid soils amended with biochar alone or combined with mineral and organic fertilizers

Semi-arid soils cover a significant area of Earth s land surface and typically contain large amounts of inorganic C. Determining the effects of biochar additions on CO2 emissions fromsemi-arid soils is therefore essential for evaluating the potential of biochar as a climate change mitigation strategy. Here, we measured the CO2 that evolved from semi-arid calcareous soils amended with biochar at rates of 0 and 20 t ha?1 in a full factorial combination with three different fertilizers (mineral fertilizer, municipal solid waste compost, and sewage sludge) applied at four rates (equivalent to 0, 75, 150, and 225 kg potentially available N ha?1) during 182 days of aerobic incubation. A double exponential model, which describes cumulative CO2 emissions from two active soil C compartments with different turnover rates (one relatively stable and the other more labile), was found to fit verywell all the experimental datasets. In general, the organic fertilizers increased the size and decomposition rate of the stable and labile soil C pools. In contrast, biochar addition had no effects on any of the double exponential model parameters and did not interact with the effects ascribed to the type and rate of fertilizer. After 182 days of incubation, soil organic and microbial biomass C contents tended to increase with increasing the application rates of organic fertilizer, especially of compost, whereas increasing the rate of mineral fertilizer tended to suppress microbial biomass. Biochar was found to increase both organic and inorganic C contents in soil and not to interactwith the effects of type and rate of fertilizer on C fractions. As a whole, our results suggest that the use of biochar as enhancer of semi-arid soils, either alone or combined with mineral and organic fertilizers, is unlikely to increase abiotic and biotic soil CO2 emissions.

Effects of organic fertilizers on the vegetative, nutritional, and productive parameters of blueberries ‘Corona’, ‘Legacy’, and ‘Liberty’

Organic farming does not allow using certain inputs, such as N, which differ in nutrient release rates and dynamics. To evaluate the effect of different organic fertilizers on the vegetative, nutritional, and productive parameters of blueberries ( Vaccinium corymbosum L.), a pot experiment was conducted in three consecutive seasons in a sandy soil of south-central Chile using ‘Corona’, ‘Legacy’ and ‘Liberty’. The following fertilizers were evaluated: compost (CM), Purely Grow (PG), Purely Lysine (PL), Fertil (F), blood meal (BM), lupine meal (LM), along with a control treatment without fertilization (C) and two conventional treatments with urea (CF) and sodium nitrate (S). Results indicate that vegetative growth and leaf N concentration prior to senescence were different among cultivars in the three evaluated seasons. The highest leaf N concentration was recorded in ‘Corona’ followed by ‘Legacy’ and ‘Liberty’ while levels tended to increase in the seasons. Quick-release N sources had greater effects on these parameters but with differences among cultivars. Fruit yield and weight were higher in ‘Corona’ followed by ‘Legacy’ and ‘Liberty’. Fruit yield was generally higher when using LM and F and showed no effect on fruit weight. Leaf chlorophyll content was higher in ‘Corona’ followed by ‘Legacy’ and ‘Liberty’, which increased when using CF, LM, BM, and PG. Finally, the organic fertilizer and blueberry cultivar that obtained the highest values for most of the evaluated parameters were LM and Corona, respectively.

Fertilizers applied to certified organic tomato culture

The tomato culture demands large quantities of mineral nutrients, which are supplied by synthetic fertilizers in the conventional cultivation system. In the organic cultivation system only alternative fertilizers are allowed by the certifiers and accepted as safe for humans and environment. The chemical composition of rice bran, oyster flour, cattle manure and ground charcoal, as well as soils and tomato fruits were evaluated by instrumental neutron activation analysis (INAA). The potential contribution of organic fertilizers to the enrichment of chemical elements in soil and their transfer to fruits was investigated using concentration ratios for fertilizer and soil samples, and also for soil and tomato. Results evidenced that these alternative fertilizers could be taken as important sources of Br, Ca, Ce, K, Na and Zn for the organic tomato culture.

Effects of Organic and Inorganic Fertilizers on Growth and Yield of Banana (Musa AAA cv. Malindi) in Oman

The Sultanate of Oman is located on the south-eastern coast of the Arabian Peninsula, which lies on the south-western tip of the Asian continent. The strategic geographical locations of the Sultanate with its many maritime ports distributed on the Indian Ocean have historically made it one of the Arabian Peninsula leaders in the international maritime trade sector. Intensive trading relationships over long time periods have contributed to the high plant diversity seen in Oman where agricultural production depends entirely on irrigation from groundwater sources. As a consequence of the expansion of the irrigated area, groundwater depletion has increased, leading to the intrusion of seawater into freshwater aquifers. This phenomenon has caused water and soil salinity problems in large parts of the Al-Batinah governorate of Oman and threatens cultivated crops, including banana (Musa spp.). According to the Ministry of Agriculture and Fisheries, the majority of South Al-Batinah farms are affected by salinity (ECe > 4 dS m-1). As no alternative farmland is available, the reclamation of salt-affected soils using simple cultural practices is of paramount importance, but in Oman little scientific research has been conducted to develop such methods of reclamation. This doctoral study was initiated to help filling this research gap, particularly for bananas. A literature review of the banana cultivation history revealed that the banana germplasm on the Arabian Peninsula is probably introduced from Indonesia and India via maritime routes across the Indian Ocean and the Red Sea. In a second part of this dissertation, two experiments are described. A laboratory trial conducted at the University of Kassel, in Witzenhausen, Germany from June to July 2010. This incubation experiment was done to explore how C and N mineralization of composted dairy manure and date palm straw differed in alkaline non-saline and saline soils. Each soil was amended with four organic fertilizers: 1) composted dairy manure, 2) manure + 10% date palm straw, 3) manure + 30% date palm straw or 4) date palm straw alone, in addition to un-amended soils as control. The results showed that the saline soil had a lower soil organic C content and microbial biomass C than the non-saline soil. This led to lower mineralization rates of manure and date palm straw in the saline soil. In the non-saline soil, the application of manure and straw resulted in significant increases of CO2 emissions, equivalent to 2.5 and 30% of the added C, respectively. In the non-amended control treatment of the saline soil, the sum of CO2-C reached only 55% of the soil organic C in comparison with the non-saline soil. In which 66% of the added manure and 75% of the added straw were emitted, assuming that no interactions occurred between soil organic C, manure C and straw C during microbial decomposition. The application of straw always led to a net N immobilization compared to the control. Salinity had no specific effect on N mineralization as indicated by the CO2-C to Nmin ratio of soil organic matter and manure. However, N immobilization was markedly stronger in the saline soil. Date palm straw strongly promoted saprotrophic fungi in contrast to manure and the combined application of manure and date palm straw had synergistic positive effects on soil microorganisms. In the last week of incubation, net-N mineralization was observed in nearly all treatments. The strongest increase in microbial biomass C was observed in the manure + straw treatment. In both soils, manure had no effect on the fungi-specific membrane component ergosterol. In contrast, the application of straw resulted in strong increases of the ergosterol content. A field experiment was conducted on two adjacent fields at the Agricultural Research Station, Rumais (23°41’15” N, 57°59’1” E) in the South of Al-Batinah Plain in Oman from October 2007 to July 2009. In this experiment, the effects of 24 soil and fertilizer treatments on the growth and productivity of Musa AAA cv. 'Malindi' were evaluated. The treatments consisted of two soil types (saline and amended non-saline), two fertilizer application methods (mixed and ring applied), six fertilizer amendments (1: fresh dairy manure, 2: composted dairy manure, 3: composted dairy manure and 10% date palm straw, 4: composted dairy manure and 30% date palm straw, 5: only NPK, and 6: NPK and micronutrients). Sandy loam soil was imported from another part of Oman to amended the soil in the planting holes and create non-saline conditions in the root-zone. The results indicate that replacing the saline soil in the root zone by non-saline soil improved plant growth and yield more than fertilizer amendments or application methods. Particularly those plants on amended soil where NPK was applied using the ring method and which received micronutrients grew significantly faster to harvest (339 days), had a higher average bunch weight (9.5 kg/bunch) and were consequently more productive (10.6 tonnes/hectare/cycle) compared to the other treatments.

The effects of organic and conventional fertilizers on cereal aphids and their natural enemies

Aphids are important pests of spring cereals and their abundance and the impact of their natural enemies may be influenced by fertilizer regime.2We conducted a 2-year field study investigating the effects of organic slow-release and conventional fertilizers on cereal aphids, hymenopteran parasitoids and syrphid predators and considered how the effects of fertilizers on barley morphology and colour might influence these species.3Barley yield was greater in conventionally fertilized pots. Barley morphology was also affected by treatment: vegetative growth was greater under conventional treatments. Barley receiving organic fertilizers or no fertilizer was visually more attractive to aphids compared with plants receiving conventional fertilizers.4Aphids were more abundant in conventionally fertilized barley but the reason for this increased abundance was species specific. Metopolophium dirhodum was responding to fertilizer effects on plant morphology, whereas Rhopalosiphum padi was sensitive to the temporal availability of nutrients.5Syrphid eggs were more numerous in conventionally fertilized pots, whereas the response of parasitoids appeared to be dependent on the abundance of aphids, although the number of parasitoid mummies was low in both years.6This research shows that the fertilizer treatment used can affect numerous characteristics of plant growth and colour, which can then influence higher trophic levels. This knowledge might be used to make more informed fertilizer application choices.

Effects of Organic and Inorganic Fertilizers on the Growth of NH-Ae 47-4 Variety of Okra

The paper evaluates the effects of organic and inorganic fertilizers on the growth of okra (variety NH-Ae 47-4. Organic fertilizers (cow dung and poultry droppings) and inorganic (NPK 15:15:15 and Urea 64:0) fertilizers were used for the experiment. The fertilizers were weighed and applied at 5g, 10g and 15g and were replicated three times and each having a control. Vegetative growth parameters taken include, shoot fresh weight (g), dry weight (g), plant height (cm), leaf number, stem girth (cm), leaf area (cm2). The results obtained from the experiment showed that the effect of the treatments were significantly difference from the control for all the parameters accessed with urea fertilizer having least effect. Plants treated with poultry litters have best performance by recording the highest fresh and dry weight (0.39g) at 4 weeks after planting (WAP); highest stem height 29.33cm for all the concentrations applied. Similarly, it has highest leaf area and stem girth (64.67cm2and 2.23cm respectively) at 8WAP.

Nitrogen fertilization of coffee: organic compost and Crotalaria juncea L.

Information concerning the response of coffee to organic fertilizers is scarce. This study evaluates the effect of different doses of compost and Crotalaria juncea L. on growth, production and nitrogen nutrition of coffee trees. The treatments consisted of compost at rates of 25, 50, 75 and 100% of the recommended fertilization, with or without the aerial part of C. juncea. C. juncea was grown with NH4-N (2% 15N) and applied to coffee. The use of C. juncea increased growth in height and diameter of the coffee canopy. In the first year, the percentage of N derived from C. juncea reached 8.5% at seven months and 4.1% at fifteen months after fertilization. In the second year, the percentage of N derived from C. juncea reached 17.9% N at the early harvest, five months after fertilization. Increased rates of compost increased pH , P , K , Ca , Mg , sum of bases , effective CEC, base saturation and organic matter and reduced potential acidity. 15N allowed the identification of the N contribution from C. juncea with percentage of leaf N derived from Crotalaria juncea from 9.2 to 17.9%.

Physical properties and organic carbon content of a Rhodic Kandiudox fertilized with pig slurry and poultry litter

The impact of pig slurry and poultry litter fertilization on soils depends on the conditions of use and the amounts applied. This study evaluated the effect of organic fertilizers after different application periods in different areas on the physical properties and organic carbon contents of a Rhodic Kandiudox, in Concordia, Santa Catarina, in Southern Brazil. The treatments consisted of different land uses and periods of pig and poultry litter fertilization: silage maize (M7 years), silage maize (M20 years), annual ryegrass pasture (P3 years), annual ryegrass pasture (P15 years), perennial pasture (PP20 years), yerba mate tea (Mt20 years), native forest (NF), and native pasture without manure application (P0). The 0-5, 5-10 and 10-20 cm soil layers were sampled and analyzed for total organic carbon, total nitrogen and soil physical properties such as density, porosity, aggregation, degree of flocculation, and penetration resistance. The organic carbon levels in the cultivated areas treated with organic fertilizer were even lower than in native forest soil. The organic fertilizers and studied management systems reduced the flocculation degree of the clay particles, and low macroporosity was observed in some areas. Despite these changes, a good soil physical structure was maintained, e.g., soil density and resistance to penetration were below the critical limits, whereas aggregate stability was high, which is important to reduce water erosion in these areas with rugged terrain in western Santa Catarina, used for pig and poultry farming.

Spectroscopic quantification of soil phosphorus forms by 31p-nmr after nine years of organic or mineral fertilization

Long-standing applications of mineral fertilizers or types of organic wastes such as manure can cause phosphorus (P) accumulation and changes in the accumulated P forms in the soil. The objective of this research was to evaluate the forms of P accumulated in soils treated with mineral fertilizer or different types of manure in a long-term experiment. Soil was sampled from the 0-5 cm layer of plots fertilized with five different nutrient sources for nine years: 1) control without fertilizer; 2) mineral fertilizer at recommended rates for local conditions; 3) 5 t ha-1 year-1 of moist poultry litter; 4) 60 m³ ha-1 year-1 of liquid cattle manure and 5) 40 m³ ha-1 year-1 of liquid swine manure. The 31P-NMR spectra of soil extracts detected the following P compounds: orthophosphate, pyrophosphate, inositol phosphate, glycerophosphate, and DNA. The use of organic or mineral fertilizer over nine years did not change the soil P forms but influenced their concentration. Fertilization with mineral or organic fertilizers stimulated P accumulation in inorganic forms. Highest inositol phosphate levels were observed after fertilization with any kind of manure and highest organic P concentration in glycerophosphate form in after mineral or no fertilization.

The influence of shade and organic fertilizer treatments on the physiology and establishment of Theobroma cacao clones

Aims: This experiment aimed to determine whether the soil application of organic fertilizers can help the establishment of cacao and whether shade alters its response to fertilizers. Study Design: The 1.6 ha experiment was conducted over a period of one crop year (between April 2007 and March 2008) at the Cocoa Research Institute of Ghana. It involved four cacao genotypes (T 79/501, PA 150, P 30 [POS] and SCA 6), three shade levels (‘light’, ‘medium’ and ‘heavy’) and two fertilizer treatments (‘no fertilizer’, and ‘140 kg/ha of cacao pod husk ash (CPHA) plus poultry manure at 1,800 kg/ha). The experiment was designed as a split-plot with the cacao genotypes as the main plot factor and shade x fertilizer combinations as the sub-plots. Methodology: Gliricidia sepium and plantains (Musa sapientum) were planted in different arrangements to create the three temporary shade regimes for the cacao. Data were collected on temperature and relative humidity of the shade environments, initial soil nutrients, soil moisture, leaf N, P and K+ contents, survival, photo synthesis and growth of test plants. Results: The genotypes P 30 [POS] and SCA 6 showed lower stomatal conductance under non-limiting conditions. In the rainy seasons, plants under light shade had the highest CO2 assimilation rates. However, in the dry season, plants under increased shade recorded greater photosynthetic rates (P = .03). A significant shade x fertilizer interaction (P = .001) on photosynthesis in the dry season showed that heavier shade increases the benefits that young cacao gets from fertilizer application in that season. Conversely, shade should be reduced during the wet seasons to minimize light limitation to assimilation. Conclusion: Under ideal weather conditions young cacao exhibits genetic variability on stomatal conductance. Also, to optimize plant response to fertilizer application shade must be adjusted taking the prevailing weather condition into account.