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Biochar (BC) is presented as an amendment based on biomass pyrolysis residue that promotes an increase in the amount of beneficial bacterial and mycorrhizal communities and the quantity of elemental nutrients for plant fertility; in addition, by its characteristics, it provides recalcitrant carbon, generates physicochemical changes, such as an increase in pH, increase in water retention in soil and cation exchange capacity. Most studies about BC focus on evaluating the results in physicochemical variables into soils, however, few studies show and explain reasons because BC increases beneficial bacterial and mycorrhizal communities to plant growth, for this reason is necessary to selectively analysis to define the mechanisms between BC and microorganisms. This review examines publications of the last 12 years of research on BC in different databases (ScienceDirect, Scopus, Springerlink, SciELO, Google Scholar), focusing on the years (2020-2022), to elucidate the underlying mechanisms that let the interaction between BC-soil microbial communities and its benefits as an agricultural amendment. An accepted hypothesis is the high porosity into BC that serves as a “microhabitat” since it allows ideal conditions of space, temperature, humidity, air, and food growing levels of rhizobacteria and mycorrhizal fungus involved in the solubilization of nutrients such as N, P and K increasing the exo-enzymatic activity of dehydrogenase, β-glucosidase, urease between others improving soil fertility and plant growth. [ABSTRACT FROM AUTHOR]

Contextualization: Advance knowledge of soil quality is very important to decide the implementation of crops and elaborate fertilization plans.D Knowledge gap: The study contributed to the acquisition of knowledge about the condition and quality of soil, and its physicochemical parameters, as a preliminary step to designing new agricultural practices, in places where farmers did not count with soils analysis, and they were unaware that soils can have a heterogeneous composition, even at relatively short distances. Purpose: The objective was to characterize agro-chemically the soils in 15 farms in the municipality of Santa María to know their natural fertility, in a place where 3 agroecological models will be implemented as part of the project "Strategic agroecological development for the strengthening of the productive sector in the Department of Boyacá". Methodology: The samples of the soils were collected in June 2019. After processing in the laboratory, the following results were obtained: pH (potentiometric method in water or in NaF), exchangeable acidity (KCl 1N), Al exchangeable, texture (Bouyucos), CO (Walkley Black %p/v) P (Bray II), S (extraction with Ca(HPO), interchangeable bases (Ca, Mg, K, Na), cation exchange capacity, minor elements (Fe, Cu, Mn, Zn, by the modified Olsen method), electrical conductivity, N available by laboratory protocols in the form of nitrate and exchangeable ammonium (KCl), ionic relationships in soil (Ca/Mg, Ca+Mg/K, Ca/K, Mg/K). Results and conclusions: The results obtained, after the soil analysis, showed significant deficiencies in the primary macroelements N, P, K and Ca. However, there was evidence that the soils have good capacity of cation exchange, and that stimulate the retention and exchange of nutrients for the plants. Therefore, it was concluded that the soils that were studied are suitable for the implementation of agroecological models, despite the deficiencies presented by the agrochemical elements. These evidence should be considered in the fertilization plans to fill these deficiencies, based on the requirements of each crop. These can be achieved by applying organic amendments, phosphoric rocks, calcareous, among others. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate the in vitro and ex vitro combination of P. chlamydosporia (IMI SD 187) and Trichoderma asperellum (Ta. 13) in the acclimatization of banana vitroplants Bluggoe type (AABB) 'FHIA-03'. Firstly, the in vitro compatibility, through space competence (radial growth) and growth inhibition percentage at 24, 48, and 120 h, was assessed by the dual culture technique. In second place, it was evaluated the application of these fungi separately or in combination during the ex vitro adaptation phase of the vitroplants. In total, 12 treatments were included, the treaments with each fungus and the control without fungus. The vitroplants were transplanted into polypropylene trays of 70 alveolus containing red ferralitic lixiviated soil and organic amendment (1:3 v/v) as substrate. P. chlamydosporia strain IMI SD 187 (KlamiC® Bionematicide) was applied with T. asperellum strain Ta.13 (SevetriC Biofungicide) by submerging the root before transplanting or by spraying the plant at 3 and 20 days post planting. The trays were randomly arranged in the adaptation area. At 30 days, the plant vegetative growth and the substrate and root colonization by P. chlamydosporia were assessed. In vitro, T. asperellum grew faster than P. chlamydosporia, but there was no direct hyphal contact between them. P. chlamydosporia colonized the root system and the rhizosphere of banana vitroplants when this fungus was applied separately or in combination with T. asperellum; both fungi promoted vitroplant growth. The results show that P. chlamydosporia and T. asperellum are good candidates for banana biomanagement strategies. [ABSTRACT FROM AUTHOR]

This article is a review of the use of organic amendments in the immobility of cadmium in contaminated agricultural soils. Cadmium (Cd) has become a global problem since industrialization began and since the implementation of intensive agricultural practices. Cadmium remains as an omnipresent environmental problem since it is a highly toxic metal that persists in the soil for long periods due to its minimal microbial and chemical loss. Currently, there is public awareness about the implications of agricultural soils contaminated with cadmium. Therefore, there is increased interest in developing and applying cost-effective, friendly, and environmentally friendly techniques such as in situ immobilization using organic amendments. It is concluded that organic amendments have the potential value to reduce Cd uptake by plants and improve immobilization by adsorption, ion exchange, complexation and precipitation. [ABSTRACT FROM AUTHOR]

The objective of this study was to validate the application of P. chlamydosporia strain IMI SD 187 (a.i. of bionematicide KlamiC®) in the agronomic management strategy for plantain vitroplants (Musa paradisiaca L.) during the ex vitro adaptation phase. In a first assay, the in vitro compatibility of P. chlamydosporia, with the products FitoMas, Urea, Cuproflow, Bayfolan, and Dimethoate added to the culture medium, was evaluated, taking into account the fungal radial mycelial growth and sporulation. In a second assay, these products were combined with the strain IMI SD 187, during the acclimatization phase of vitroplants. P. chlamydosporia was applied at 5,6 x 105 clamidospore.vitroplant-1 by sprinkling the vitroplants at 3 and 20 days after transplanting, alone or in combination with agrochemicals and bioestimulant, on vitroplants of different size, cultivar 'CEMSA - ?'. The vitroplants were transplanted into polypropylene trays of 70 alveolus containing substrate: ferralitic red lixiviade soil and organic amendment (1:3 v/v); and they were distributed in the acclimatization area under randomize block design. The plant growth and fungal colonization on the substrate and roots were evaluated. Cuproflow was considered high toxic and the rest of the products evaluated were compatibles with the fungus. P. chlamydosporia colonized the vitroplants rhizosphere, and plant growth parameters were increased: plant length, pseudo-stem diameter and foliate and root fresh masses. The major growth stimulation was achieved on smaller size vitroplants. [ABSTRACT FROM AUTHOR]

The thermochemical transformation of biomass, i.e., to generate electrical power, produces a solid residue named biochar. Biochar properties allow using it in different applications, including soil amendments. In this work, two specific types of biochar are evaluated as potential substrate substitutes in open small-scale cultures. A crop of Solanum lycopersicum (tomato) was used as reference, and the effect on plant development and harvest (number, diameter and weight of fruits) was observed when replacing the commercial substrate by biochar in proportions of 0, 20, 50, 80 and 100%. It was observed that with substitutions of 20% and 50% of substrate by biochar, the plants show a normal development and the tomato production is comparable to the one obtained in the absence of biochar; However, when replacing 80% or 100% of the substrate by biochar, the effect on plant growth is negative, apparently due to the absence of nutrients. From an economic and environmental perspective, these results are quite satisfactory; since using 20% or 50% of biochar can represent significant savings for the farmer (less use of substrates), while also giving utility to agro-industrial waste (biochar). [ABSTRACT FROM AUTHOR]

Se presenta una serie de resúmenes para trabajos finales de graduación de Ingeniería Agronómica, incluyendo uno sobre el rendimiento de grano y forraje en La Pampa, Argentina, uno sobre el efecto del procesamiento del grano de maíz en el crecimiento de terneros y uno sobre la aplicación de enmiendas en suelos salinizados.

Chicken production wastes, principally poultry manure ( layers ) and litter (from chickens for fattening), may impact negatively on the environment, contributing to soil, water and air pollution. Aerobic stabilization through composting is an alternative to reduce contamination. This study aims to evaluate the composting process in two mixtures with different percentages of poultry manure of laying chickens and broiler poultry litter. Two mixtures were composted containing 81% and 70% of poultry wastes for 16 weeks. The analytical parameters were: temperature (T°), pH, electrical conductivity (EC), humidity (H), cationic exchange capacity (CEC), total organic carbon (TOC), amonium (NH4 +), nitrate (NO3 - ), total nitrogen (TN), soluble carbon soluble (SC) were determined in each treatment. The final compost A and B characteristics were 7,1 - 6,8, CE 3,3 - 2,9 (mS.cm-1), COT 14,8 - 17,9%, NT 0.97 - 0.88%, NH4 + 501 - 144,9 mg kg-1, NO3 - 552,3 - 543,0 mg kg-1 respectively. The composting process may be a tool to stabilize poultry wastes, minimizing its environmental damage. [ABSTRACT FROM AUTHOR]

Waste generation, manifest the complex relationship between society and nature. Biosolids are a byproduct of urban waste water treatment and final disposal is an environmental problema. One option is to use as organic amendment in agricultural soils. In the municipality of Puebla, Mexico generated 200 t d-1 of biosolids used in rural agricultural soils in rural areas. The effects caused to the soil and the environment have been studied. The effects socioeconomics produced to farmers and their families, is an unexplored area. A survey was conducted among farmers in the town of La Paz Tlaxcolpan, Puebla, applying biosolids on their land. The aim of this study was to evaluate the magnitude of the economic and social benefits they receive from using biosolids. There is an increase in yields ranging from 25% to 400%. The economic and social benefits are minimal. [ABSTRACT FROM AUTHOR]

The effect of the presence of organic amendment on the activity of two selected strains of Pochonia chlamydosporia var. catenulata (Kamyschko ex Barron and Onions) Zare & Gams on Meloidogyne enterolobii Yang & Eisenback was evaluated. The fungal strains studied were IMID SD 187 from Cuba and CG1006 from Brazil. The experiment was carried out in Embrapa-Cenargen, Brasilia-DF (Brazil), under greenhouse conditions during February-April, 2011. An agricultural soil (sterilized and not sterilized) was used and combined with the presence-absence of organic amendment (Bioplant) (1:1 v/v). Four treatments were prepared inoculating polyethylene bags with 4kg of substrate with 5000 chlamydopores.g-1 of substrate of each of the strains, leaving non-inoculated bags as controls. Then, a chicory plant was transplanted into each bag, and 5000 juveniles/eggs of M. enterolobii were added. Colonization of both strains of P. chlamydosporia var. catenulata was in the order of 103-104 UFC,g-1 in the soil and roots. The percentages of egg mass colonization and egg parasitism of the strain CG1006 were higher, between 77-92% and 71-78%, than those of IMI SD 187, which were 58-89% and 37-74%, respectively. Although the galling index of M. enterolobii was not reduced by the effect of none of the fungi, the number of healthy egg was reduced compared with the control. The results indicated that the presence of organic amendment did not influence the activity of the native strain significantly, but it did influence that of the foreign strain (IMI SD 187), fundamentally in natural soil. Therefore, the pertinence of studies in non- sterilized soils was ratified for offering more reliable information for the selection of promising strains as biological control agents of nematodes and their use within nematode management strategies. [ABSTRACT FROM AUTHOR]

Usually, fertility of soils is evaluated based on chemical, physical or biological analysis, comparing the results obtained with preset calibration scales. This is in some way tedious and with little or any spacid visualization of their edaphic behavior. Taking on consideration the abovementioned features, a work was developed at Las Papas farm belonging to the National Institute of Agricultural Sciences (INCA), whose main objective was to elaborate thematic maps of pH, organic matter, assimilable P and exchangeable cations to use them in the handling of there soils. The soil sampling was carried out with a drill, to a depth of 0-20 cm, using the zigzag method, and where sampled chemical analyses were carried out, using the analytic techniques used at the laboratory of INCA where each lot, whit 4,6 ha were evaluated, taking five composed samples for area. The maps show the prevalence of lightly sour to sow soils, with low to medium contents of organic material and high content of P and high to medium in K, low values of Ca and Mg, although in the last one, with few exceptions, there exist areas with medium content. Take decisions about the fertilization, amendments and the crops to grow, on that soils. [ABSTRACT FROM AUTHOR]

Natural and anthropic factors may produce soil acidification in temperate areas, causing deficiencies/unbalances of basic nutrients, particularly Ca and Mg. This problem requires regional experimentation to generate regulations for the election of the amendment, rate and application form. The aim of this study was to compare the alfalfa yield of three areas in the argentine temperate region, the basic nutrient concentration in the plants, and the changes in edaphic properties caused by the different rates and types of amendments. Two trials were conducted in Typic Argiudolls and one in an Entic Hapludoll of Buenos Aires, Santa Fe and Córdoba provinces. The treatments consisted in the application of 0 and 700, or 1,000, 1,500 and 2,000 kg ha-1 of shell/calcite and dolomite, according to the site. The effect of the additional application of 200 kg ha-1 of gypsum was evaluated. Alfalfa dry matter yield, foliar concentration of Ca and Mg and the effect of the treatments on edaphic properties were measured. The smaller rates (700-1,000 kg ha-1), with or without gypsum, produced the greatest yield increases. These increases were of 9, 16.5 and 18.8% respect to the control, for the trial of Santa Fe (C1000; 6 harvests), Buenos Aires (C1000, 5 harvests) and Córdoba (C700, 10 harvests), respectively, and of 11.7; 14.4 and 9.1% respect to the control, for the trial of Santa Fe (D1000), Buenos Aires (D1000) and Córdoba (D700), respectively. The residuality extended all along the evaluation time (27 months). The treatments did not produce mayor differences in the foliar concentrations of Ca and Mg, although they increased the availability of both nutrients per area unit at the expense of the increase of yield, with maximums of 9.4 kg ha-1 of Ca and 7.6 kg ha-1 of Mg. After two years of liming, the soils still showed the effects in the reduction of the real acidity (0.1-1.1 pH units) and in the potential acidity (0.1-0.9 unit of pH) in the superficial layer. The cationic exchange capacity increased from 0.2 to 5.3 cmol kg-1, and the exchangeable Ca up to a maximum of 2.6 cmol kg-1. Liming produced a negative impact on the extractable P levels, suggesting the need to monitor P levels when following this practice. [ABSTRACT FROM AUTHOR]

Edaphic acidity causes productivity problems due to microbiological and nutritional disturbances and Al3+ phytotoxicity. The purpose of this study was to: a) evaluate the cation exchange capacity and the amount of basic nutrients present in some acid soils of the Pampa Region, b) evaluate the exchangeable Al3+ concentration, and c) assess the effect of different rates and types of alkaline amendments on the exchange complex. Real and potential pH, the exchange complex and exchangeable Al3+ were studied in 10 acidic Argiudoll and Hapludoll soils. The same analyses were conducted on an Entic Hapludoll treated with different rates and types of amendments. In addition, the cation exchange capacity at each soil pH level was evaluated. The soils presented Ca+2 deficiency relative to Mg+2 and K+, and to a lesser extent low Mg+2 concentrations relative to K+. High to slightly acidic real pH corresponded with a high/moderately acidic potential pH. Liming increased the cation exchange capacity and exchangeable Ca+2. Although exchangeable Al3+ was not present at toxic levels in the untreated soils, addition of any amendment combination and rate reduced its concentration 4 to 5-fold. Gypsum did not modify the calcite effect on Al3+, but its addition to dolomite reduced carbonate efficiency. For each amendment, the best rates for lowering exchangeable Al3+ were 1,500 and 2,000 kg ha-1. [ABSTRACT FROM AUTHOR]

A sustainable approach to dealing with waste generated in agriculture is its application in horticultural production. The aim of this study was to evaluate the effect of applying different types and quantities of organic amendments, compostvermicompost (LC) and bone meal (HH), in the production of beet and its impact on soil physical and chemical properties. The experiment was conducted in the urban organic vegetable garden at the Facultad de Agronomía-UBA (FAUBA) in a Typical Argiudoll. Soil organic carbon (CO), particulate organic carbon (COP), bulk density (DA), extractable phosphorus (Pe), pH, electrical conductivity (EC) and cation exchange capacity (CEC) were evaluated. Dry matter yield (DM) and nutrients in dry matter (mg NPK kg MS-1) were determined on beet. The results showed some differences in edaphic variables, yield and nutrient content in plant dry matter. In the soil, COP, CIC, EP and EC were increased with LC and LC HH. Vermicompost and bone meal combined and applied at double rates proved to be the best amendment for the maintenance of soil properties and beet productivity. [ABSTRACT FROM AUTHOR]

The objective of this work was to determine the effect of nitrogen, phosphorus and potassium applied to the soil, on yield and bromatological quality of mulberry. The experiment was conducted in Costa Rica at 1542 masl, in a mulberry plantation with a population of 25000 plants/ha established in 2002. The plants were homogenized by prunning at 60 cm above the soil surface and 84 days after were harvested for the evaluation. The annual mulberry dry matter yield showed important differences between applied levels of nitrogen, phosphorus and potassium (p<0.05). The highest concentration of dry matter was observed with 112.5 kg of N/ha/year, 30 kg of P/ha/year and 225 kg K/ha/year. The highest percentage of crude protein was obtained with 112.5 kg of N/ha/year but with similar results (p>0.05) were observed when different amounts of phosphorus and potassium were applied. The concentration of neutral detergent fiber was affected (p<0.05) when the levels of nitrogen were increased and considerable variations were observed with addition of phosphorus and potassium. The different levels of NPK did not show important effects on acid detergent fiber; however, as the nitrogen levels increased the hemicelulose decreased (p<0.05), and the cellulose augmented with high levels of nitrogen and phosphorus, but decreased significantly with elevated amounts of potassium. The production of dry matter resulted highly significant (p<0.01) when nitrogen, phosphorus and potassium where applied together, but crude protein and neutral detergent fiber did not show the same pattern (p>0.05). [ABSTRACT FROM AUTHOR]

Anthurium is a much appreciated ornamenta plant for its elegant leaves and beautiful flowers. It is a slowly growing crop that completes its physiological cycle by going through three stages or phases: adaptation, acclimatization and nursery. Tissue culture is its most appropriate reproduction form and its development is based on available slightly acid -3 substrates with a bulk density of about 0.60 kg.cm-3 and an estimated organic matter content of 25 %. It also requires well aerated substrates. Besides, it is necessary to take into account other influential aspects to obtain a good seedling, such as mineral fertilization, use of growth promoters and, in the last decades, addition of soil microorganisms as biofertilizers. Ex perimental works were developed at the nursery stage in the National Institute of Agricultural Sciences (INCA), over the period of June/2004- January/2006, with the objectives of localizing and characterizing adequate carriers to satisfy plan needs; preparing, characterizing and defining the possible influence of different substrate formulas on plants within this stage; determining the influence of different substrate pH values as well as evaluating the effects of AMF biofertilization on seedling growth in tested substrates. Results showed Anthurium answer to different substrates used, standing out those mixing acid peat+filter cake+zeolite, so proving the significance of substratum pH on crop development and growth, 6,5 being the most appropriate one. In general, a positive effect was recorded after applying mycorrhiza biofertilizers to Anthurium growth, these treatments showing a higher growth than those without it. [ABSTRACT FROM AUTHOR]

This research work was carried out at the National Institute of Agricultural Sciences (INCA), with the aim of evaluating the agricultural use impact of urban sewage sludge from «Quibú» Purifying Station of Residual Waters. Biosolids obtained through anaerobic digestion and applied to a compacted Red Ferralitic soil increased oxidizing organic matter, assimilable phosphorus and changeable calcium contents. Total contents of bacteria, fungi and actinomyces became higher in the soil, whereas pathogen populations were minimal and in some cases null. On the other hand, it was observed that this organic residual had a positive influence on tomato plant production and its components, without affecting fruit quality. In general, the agricultural use of biosolids proved to be a viable choice in agricultural exploitation systems. [ABSTRACT FROM AUTHOR]

During more than 15 years investigations in experimental stations and in production conditions were carried out with the hypothesis that a decrease of the amounts of nitrogen applied on potato at present was possible without yield affectation while the environmental damages could be diminished. Results of some of representative experiments carried out in three important soils are showed. Increasing amounts of nitrogen as urea or ammonium nitrated were tested in experimental stations (0-220 kg N/ha) and the best amounts previously obtained were compared in validation tests with those applied in production conditions that year (from 186 to 220 kg N/ha), as ammonium sulphate as component of a complete formula plus the other sources previously mentioned. The fertilizer was split in two applications: one at the plantation moment and another one 25-30 days later. The results showed that the N amounts usually applied under production conditions (more than 180 kg N/ha) were unnecessary high for yields until 35 t/ha and could decrease the yields, even causing the annulment of the potential fertilizers effect, affecting the potato tuber formation and favouring the incidence of diseases in addition to represent a danger for the underground waters of the respective zones that in occasions have reached concentrations not advisable for human consume. The most convenient amounts ranged generally between 120 and 150 kg N/ha. [ABSTRACT FROM AUTHOR]

Introduction. The increase in the organic products demand has generated a higher consuming of composted materials, in order to increase the chemical and physical quality of the soils and guarantee better crops. Besides, laws are being created and implemented to rule the parameters for the organic manure production, processing and application in Colombia and worldwide. There are many reasons to control the process in a production plant: The smell, the standardization of properties to sanitize the final product and the compost quality. Objective. To evaluate the effect of the pH on the micro organisms growth in compostation systems under passive ventilation and no ventilation. Materials and Methods. The compostation process was made on the field with two piles which were taken to their maturation stage. The samples were collected and incubated in enriched BHI broth and with a pH adjusted to 5, 6, 7, 8 and 9. 24 hours later they were seeded to count the bacteria, moulds and leavenings. Another sample was collected at a field pH and the microorganisms were counted. In the statistic evaluation, the SAS program was used. Results. The pH effect is significant in the growth of bacteria, moulds and leavenings. For the bacteria, the most influent pH was 5 for both piles. For the moulds and leavenings it was 9 for the ventilated piles. Conclusion. The results show the significant effect of pH on the growth of colony forming units of mesophilic and thermophilic bacteria, moulds and leavenings. This fact cannot be evaluated keeping away the others that intervene in the compostation, such as ventilation, temperature, humidity and kind of substrate used as raw material. [ABSTRACT FROM AUTHOR]

This work was carried out in the farm «101»; belonging to the UBPC «La Julia» of the ECV «Batabanó», with an electric irrigation system, kind central pivot. The general objective of the investigation is to propose recommendations for the differentiated application of fertilizers for quadrants for the potatoes crop using technical of Precision Farming, studying the chemical properties fertility of the soil. The main chemical characteristic of the soil were determined, demonstrating the existent differences from a quadrant to another. They were calculated, also, the differentiated doses of fertilization for the crop of the potato in the farm «101» that guarantee a saving of 16,21 t of NPK (9-13-17) and 1,16 t of UREA (46-0-0), meaning a decrease of the production cost for the ECV in $4 988,53 (NM) and a saving of for the MINAG of $3 278,51 (USD). [ABSTRACT FROM AUTHOR]

The experiment was mounted low controlled conditions, in the Center of Agricultural Investigations (CIAP), with the objective of studying the effect of different gallinaza levels on the physical and chemical conditions of five floor types: Pardo con Carbonatos, Pardo sin Carbonatos, Ferralítico rojo, Oscuro Plástico y Ferralítico cuarcítico amarillo rojizo lixiviado. The following treatments settled down: Witness, 2 t.ha-1 of Gallinaza, 4 t.ha-1 of Gallinaza, 6 t.ha-1 of Gallinaza, 8 t.ha-1 de Gallinaza, 10 t.ha-1 of Gallinaza. The results demonstrate that the good level of gallinaza for all the floor types, is of 6 t.ha-1. It could be proven that the gallinaza achieves an important effect on the assimilable P2O5 in all the floors in study. The effect of the material on the structure is marked in the Brown floors with Carbonates, Brown without Carbonates, red Ferralítico. It is demonstrated that with applying a reduced level of this organic payment (2 t.ha-1) positive answers were achieved in the floor. The practice of the use of the gallinaza lowers these approaches he/she makes viable its use from the ecological and economic point of view. [ABSTRACT FROM AUTHOR]

Land application of organic materials is a common practice in sustainable agriculture. Our aim was i) to study the effectof the incorporation of organic material at different maturity stages on the ryegrass (Lolium peremne L.) growth, and ii) to estimate the stage capable to produce the product more efficient in providing nitrogen to the plant nutrition. Four compost samples consisted of pruning waste, leaves and grass clippings were selected from four different piles at different stages of the composting process: initial non-decomposed material, 2 months old at the end of the bio-oxidative stage, 7 months old during the maturation phase, and 12 months old at the end of the maturation phase. These compost samples were used to ryegrass growing assays, and they were also added to a clay silty soil. Dry matter values were lower in Tl and T2 than in T3 and T4. Similar results were quantified when the same materials were incorporated to a soil. Nitrogen leaf content revealed that soil N immobilization had ocurred in Tl and T2 treatments. A compost, which had 7 months old during the maturation phase, did not cause any negative effect on the evaluated parameters. This compost seems to be sufficiently stable and its use would save time in compost process, compared with a compost 12 months old. [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate the influence of phosphorus (P) fertilizer placement (in-furrow incorporated or broadcast) on growth and root mycorrhizal colonization of wheat (Triticum aestivum L). Experiments were setup during the 2001 and 2002 growing seasons at four productive sites of Balcarce and Lobería with different initial availability of Bray-P. Treatments were; N; nitrogen broadcast; N broadcast and P incorporated in furrow at seedling; N and P broadcast; Control without fertilizer application. In situations with low soil P availability (lower than 11 mgkg1), the P incorporated was more efficient than the P broadcast treatment at increasing grain yield. In situations with P contents higher than 11 mg kg1, differences in grain yield were lower between the treatments of P placement. Phosphorus fertilization negatively affected myeorrhizal colonization until 15.9 mg kg1. At P concentrations higher than 15.9 mg kg1 mycorrhizal colonization remained stable at the lowest level (6.85 %). The P broadcast depressed mycorrhizal colonization; however mycorrhizal depression was lower than when P was incorporated. The lowest difference in grain yield between the P placement treatments, particularly at soil P contents higher than 11 mg kg1, could be consequence of a higher mycorrhizal colonization when P was broadcast. The fertilization strategy could be broadcast the fertilizer at rates which permit to increase the soil P at levels (between 11 and 15 mg kg1) in order to attain high yields of wheat crop without extremely depress mycorrhizal colonization. In this way, this could permit simplicity at the time of fertilization and to attain adequate grain yield taking into account the agroecosystems sustainability. [ABSTRACT FROM AUTHOR]

The present work was developed in the UBPC "Arcidez de Armas Pomo" of Topes of Collantes in Sancti-Spíritus, with the objective of determining the relationships between properties of soil and yield. The parameters showed evidence of the sensibility to changes in Red Ferralíticos of Mountain soil. They took 50 soil samples to depth of 0-20 cm being applied 10 treatments of amendments and 5 repetitions for each one (a witness as reference, NPK, 4 t/ha compost, 15 t/ha Humid Bases Residual , 4 t/ha compost+ 4 t/ha Fosfatada Calcareous , 4 t/ha compost+4 t/ha Dolomita, 15 t/ha Humid Bases Residual+4 t/ha CF, 15 t/ha Humid Bases Residual+4 t/ha D, 4 t/ha D, 4 t/ha CF) under controlled conditions. The data were processed by the statistical package Statgrafic 4.1 (for the regression relationships) and SPSS 8.0 (for the main components) in Windows 2000. The obtained results revealed that the pH KCl was an indicator capable to diagnose the problems of acidity of the soil, as well as a parameter that affects other structural properties and tenors of fertility. The properties of fertility (P2O5, K2O), physical properties (AE and FAITH) and of acidity (pH KCl and To the camb), they grouped in levels of main components, demonstrating their sensibility in the changes in the established system. [ABSTRACT FROM AUTHOR]

We determined the growth, nutrient (PO43-, NO3-, NH4+) uptake and proximate composition of Rhodomonas sp. cultured during seven days in batch culture using f/2 medium and agricultural fertilizers. The growth rate was similar with both media (μ = 0.37 and 0.38 day-1). Protein content in Rhodomonas sp. cultured with f/2 medium was higher than with agricultural fertilizers (10.7 and 8.96 pg cell-1, respectively). Carbohydrate and lipid contents decreased during the exponential growth phase and there were no significant differences (P = 0.027 and 0.08, respectively) between both experiments. Carbohydrate content was higher during the slow growth phase in cultures using f/2 medium, whereas lipid content showed little variation during the slow growth phase, but was higher in cells cultured using agricultural fertilizers. During the first five days, total phosphate uptake by Rhodomonas sp. was 39.9 μM (94.3%) in the f/2 medium and 40 μM (99%) in the agricultural fertilizer medium. A total of 667.3 μM of nitrate (72.2%) was consumed during the first four days in the f/2 medium, whereas in the agricultural fertilizer medium formulated with ammonium nitrate, ammonium uptake (418.1 μM, 78.7%) in the first three days was higher than nitrate uptake (37.7 μM, 7.3%); however, when ammonium concentration decreased to 1.83 μM, the nitrate uptake increased. In conclusion, the cellular quantity and quality of Rhodomonas sp. was similar when both media were used and agricultural fertilizers can be used in marine aquaculture programs. [ABSTRACT FROM AUTHOR]

The work was carried out in a popular orchard of the municipality of Cruces, between the months of February of 2003 and March of 2004 to evaluate the use of the payment organic fermented type "Bocashi", as alternative in the nutrition of the cultivation of the bean in popular orchards. For the elaboration of this payment inputs characteristic of the town were used, which fulfilled the required parameters of quality, as for characteristic nutritional and time of production. By means of a design of blocks the treatments were studied at random: Application of Bocashi, compost application and a witness without application and the variable height of the plants, moment of appearance of beginning of the trees were evaluated, wide and long of the leaves and the sheaths, mass of the sheaths for plant and the agricultural yield. The results indicate that the Bocashi constitutes a nutrition alternative in the cultivation of the bean in the popular orchards. [ABSTRACT FROM AUTHOR]

The compostation made from organic remains produced by municipals, can be a liability and cause damage when used as soil conditioners, because of the excess of inert materials, stinking emissions, high salinity levels, toxicity due to organic contaminants or heavy metals, immaturity of the process and the presence of pathogenic organisms. Given all this factors, it is necessary to evaluate all of the physical, chemical and microbiological parameters of the process, keeping in mind the corresponding Colombian laws on the subject, which regulates the organic materials used as fertilizers and soil conditioners in Colombia: Colombian Technical norm 5167 and the resolution 00150 of January 21st of 2003, made by the Colombian Agro-Cultural Institute, ICA. [ABSTRACT FROM AUTHOR]

The use of the organic waste and vegetable residuals in the agriculture are reason why of great importance for the benefit that it reports to the soil and the plants. A study in the demonstrative area for the production of organic matter of the Provincial Laboratory of Soils of Camagüey, was carried out where a compost formed by bovine manure, banana remains, grass and trashes was processed, with the objective of to establish a method of static compostaje and to define some parameters of its quality. An experiment bifactorial was made where the time of rest or of decomposition of the pile (3, 4, 5 and 6 months) was analyzed and the thickness of the layer of manure (5 and 10 cm). After having conformed the piles and of lapsing the established time for each case. The contents of N, P, K, Ca, Mg, C and M.O, as well as the relationship C/N and the pH were chemically determined. It conclude that the very good time of application of the static compost is to the 5 months; the thickness of the layer of appropriate bovine manure as microbial inoculum is that of 5 cm and a compost in a simple, economic way and of good quality was obtained. [ABSTRACT FROM AUTHOR]

The aim this work is to characterize the natural conditions of the Bajio Guanajuatenses' Region like cereals producer, as well as to determine the agricultural parameters for the cultivation of Esperanza malster barley variety that influence in the automated process of crop-transport. The Region was characterized for the climatological conditions during the crop period, with the precipitation indicators, relative humidity, half temperature and wind speed. To the soil conditions it was considered, the relief; the micro-relief; the soil humidity; the soil compactación before and after the cropper's step. With relationship to the cultivation, the grain yield, the plant inclination; the relationship grain/straw; the volumetric mass, the hectoliter weight and the natural losses. [ABSTRACT FROM AUTHOR]

Changes in production practices, as from conventional tillage to minimum tillage, might affect allelopathic interactions between different crops residues below the Cuban productions systems. Field experiments were conducted on typical Red Ferralitic soil in the Agricultural Enterprise April 19, of municipality Quivicán, Mayabeque province, Cuba, during two years. The objective was: to evaluate the inluence of minimum tillage systems and the allelopathic effects on the common beans (Phaseolus vulgaris, L) productions cv Tomeguín 93-N. The residues were sweet potatoes (Ipomoea batata, L) cv CEMSA 78- 354, corn (Zea mays, L) cv. Francisco, sunlowers (Helianthus annus, L) cv Cuba- Sol and commom beans (Phaseolus vulgaris, L) cv Tomeguín 93-N. These residues were incorporated into the soil a ration to 0,3 kg m². The t reatments study objects were the result of the four vegetables residues incorporated and the cont rol the t reatments were ar ranged and the random block with four replicas. The observations and determinations were: survival of the plants (reduction percentage), yield (t ha-1), and analyze of cost and crops common beans utility. The results indicated the negative inluence of minimum tillage systems in the survival of the plants and yield of common beans (Phaseolus vulgaris, L) cv Tomeguin 93- N as consequence the allelopathic effects of such residues. [ABSTRACT FROM AUTHOR]

La tendencia de muchos productores y exportadores de Melón y Sandía es bajar el uso de pesticidas en sus sistemas de producción, por lo que a partir del año 2005 se inició un proceso de capacitación y montaje de algunas biofábricas para la reproducción de microorganismos benéficos, también algunos productores adquieren los bioproductos de laboratorios nacionales o usan productos importados. En el caso de nuestra empresa, brindamos el servicio de asesoría para algunas de las fincas que poseen sus propios laboratorios, a ellos se les vende los inóculos para su reproducción y a algunos otros se les suple el producto listo para aplicar. Los organismos más utilizados en estos cultivos son: Trichoderma asperellum, Bacillus subtilis, Paecilomyces lilacinus y el consorcio de microorganismos para la descomposición de la materia orgánica y la reducción del inóculo de patógenos (Cytophaga, Lactobacillus lactis, Rhodotorula, Saccharomyces y Trichoderma reesei). Dentro de las empresas que más utilizan estas novedosas herramientas podemos citar: Melones del sol, Monserrat y María, J.M Ivando, La Ceiba, Exporpack, Agroexportador La Nena, entre otros. Como resultado de estas acciones, al día de hoy se aplican estos organismos a más de 2000 hectáreas, se ha reducido el uso de fumigantes y fungicidas de suelo y, en el caso del bromuro de metilo, se eliminó casi en su totalidad. En el caso del manejo de rastrojos de arroz y caña, con la adición de los microrganismos descomponedores, no es necesario recurrir a las quemas. [ABSTRACT FROM AUTHOR]

It is suggested that cabbage dry residues provide antagonist microorganisms to plant pathogens and they modify the pH of the soil. We used cabbage sun-dried residues, packaged and preserved in a dry environment for two and five years. They were analyzed microbiologically, and their effect on the pH of a sterile soil for 30 d, and the type and number of microorganisms they can incorporate were studied. We also determined its effect on pH, the physical, chemical and biological characteristics in five unsterilized soils for 51 days. In the residues, the Bacillus sp., Pseudomonas sp., Trichoderma sp. and Penicillium sp. predominated. In vitro, Bacillus and Pseudomonas showed antibiosis against Rhizoctonia solani and Fusarium o×ysporum f sp. lycopersi. Trichoderma and Bacillus were mycoparasites of these fungi respectively. In sterile soil, residues increased the pH from 7.57 to 8.79, and favored the development of bacteria (160×107 ufc g-1 soil), mainly from Bacillus and Pseudomonas. In four of the non-sterile soils, the pH was always significantly (P <= 0.05) lower than the control and ranged dynamically between 7.33 and 8.24; the content of assimilable nitrogen, potassium, and the bacteria g-1 in soil were increased; Bacillus and Pseudomonas were incorporated; and the development of Penicillium was promoted. [ABSTRACT FROM AUTHOR]