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The soils of Cesar present high percentages in degradation and a low productive capacity, so for their management it is necessary to implement technologies such as fertigation, in order to improve the productive capacity of the soil in a sustainable way. In this research the effect was evaluated of the application of fertigation with central pivot on Water productivity (WP) of Megathyrsus maximus cv. Agrosavia Sabanera in a soil with pH variations was evaluated under colombian dry Caribbean conditions. Five treatments corresponding to five pH ranges were determined; within each range, three experimental plots were established. The variables evaluated were dry matter production (MS), green forage (MV), dry matter percentage (% MS), stem height, plant height and macro and microelement content of the forage. Of the soil the apparent density, pH, electrical conductivity (EC) and infiltration were determined. The MS and WP ware higher when soil pH was lower than 7.8 (p < 0.05). Water productivity (WP) was higher 2.83 kg/m3 and dry matter (MS) exceeded 0.72 kg/m2 with soil pH less than 7.8; in the pH range between 5.5 and 7.8 the assimilation of nitrogen, potassium and calcium was higher (p < 0.1); greater plant development was observed in soil with pH between 5.5 and 6.9 (p < 0.05); in relation to edaphic properties, a positive correlation was observed between infiltration and stem growth and a negative correlation of stem growth versus pH, EC and manganese assimilation (p < 0.1); biomass production of Megathyrsus maximus cv. Agrosavia Sabanera is favorable when the soil pH is between 5.5 and 7.8. [ABSTRACT FROM AUTHOR]

Hops (Humulus lupulus) is a plant with potential for cultivation in the Center-South region of Paraná, Brazil. However, there are no official Brazilian recommendations for production of seedlings or fertilization and liming. The aims of this work were to evaluate the production of hop seedlings and verify the development of hop plants grown in soil with different pH values and K2O rates, in the Center-South region of Paraná, Brazil. Three experiments were carried out: i) cuttings of a plant were dipped in a 1% indole-3-butyric acid (IBA) solution and placed in different substrates - the sprouting and survival of the hop seedlings was verified; ii) hop seedlings were transplanted to a soil with different pH values (4,5; 5,5; 6,0 and 6,5) - the development and nutrients uptake by the plants was evaluated; iii) hop seedlings were transplanted to a soil with different K2O rates added - the development and K uptake by the plants was assessed. The substrate for seedling production did not influence the sprouting of hop cuttings, but the presence of IBA reduced sprouting and growth up to 41 days. The pH 5,5 value in the soil provided the best hop development by increasing the production of fresh and dry biomass in comparison with pH 4,5. Hop plants in soil with pH 6,0 and 6,5 showed lower chlorophyll content, but maintained the same nutrient uptake. The production of dry biomass of hop plants and the K content of the roots increased with the K2O rates added to the soil, However, K was not transferred to the aerial part of the plants in the initial phase of development. [ABSTRACT FROM AUTHOR]

We evaluated the use of vinasse ashes as fertilizer to forage plants. We put the vinasse to the muffle furnace at 600°C for 90 minutes to the production of ashes. It was sowed the forage plant Urochloa brizantha - cv Marandu, in polyethylene plastic bags that were kept in a greenhouse. The treatments used were application of vinasse ashes equivalent to 0, 100, 250, 500, 1000 kg/ha. We cut the plants at 30 days and 60 days in order to evaluate the production of dry matter (DM) and green matter (GM). From the soil enriched with, we took a sample to analyze. There was a correction of pH of the soil and an increase of the macrominerals phosphorus, potassium, calcium, and magnesium. The treatment with 100 kg/ha has proved to be more effective and increase on average of 18.5% the production of GM and of 24% the production of DM of the forage plant studied. We concluded that the use of vinasse ashes is a potential source of minerals to the forage plants. [ABSTRACT FROM AUTHOR]

Most of the soils for agriculture differ in their chemical, physical and biological properties the participation of each one of these determines the natural fertility that has the soil for the establishment of crops. The importance of understanding the electrochemical properties of soils as fertility parameters is currently unknown, where the determination of variables such as cation exchange capacity (CEC) and Point Zero (PCC) will promote the proper management and calibration of fertility plans. One of the key parameters to identify soils variable load or permanent load is the determination of the PCC, identified as the pH value in which both positive and negative charges are equal; therefore if natural state soil has a pH above the PCC will have a predominance of negative or high CIC charges, contrary to that if this same submit a pH value below to PCC generating high anion exchange capacity (CIA) or strong presence of positive charges. This research sought to transform the positive charges of organo-mineral complex to negative by limin different techniques, applied to trays with known amounts of soil. According to the results obtained regarding phosphorus dynamics, it is concluded that the optimum pH value for its solubility is in a range of 6,3 to 6,6, and the PCC value for the soil evaluated shows a value of 4 indicating that variable loads prevail over permanent ones. Likewise, a CICE of 4,7 is defined and a soluble phosphorus that fluctuates significantly from the application of CaCO3 that differs from the available phosphorus because it reports its highest level with the application of 4,5 Mg ha-1 of CaCO3. [ABSTRACT FROM AUTHOR]

The use of organic fertilizers such as Bocashi, Compost and chicken manure, contribute to the improvement of the physical, chemical and biological properties of the soil through the incorporation of nutrients by regulating its water balance. The effect of organic fertilizers on the physical, chemical and biological properties of an agricultural soil in Purupampa Panao, Peru was evaluated. The work area was made up of an area of 596.25 m2 with characteristics of degraded soils. The methodology was composed of a completely randomized block design (DBCA) with four treatments: control 0 kg fertilizers, Bocashi 8,500 kg ha-1, Compost 8,500 kg ha-1, manure 8,500 kg ha-1, during the months January-December 2017. Four repetitions were performed, for a total of 16 experimental units. A slight effect of organic fertilizers with Bocashi 5.69 was observed in the hydrogen potential (pH); organic matter (MO) with Bocashi 3.96% and Compost 3.85%; nitrogen (N) with 0.17% chicken manure; phosphorus (P) with chicken manure 7.63 ppm, potassium (K) with Compost 66.19 ppm. Organic fertilizers, especially chicken manure and Bocashi, showed to improve the concentration of macronutrients in the soil, especially nitrogen, so the use of Bocashi is suggested to improve the levels of macronutrients in the soil by reducing its acidity. [ABSTRACT FROM AUTHOR]

Introduction: The characteristics of coastal wetlands are the result of hydrogeomorphological interactions between the continent and the ocean, which cause an environmental gradient, hat results in different vegetation types such as mangroves, freshwater marshes, swamp forests and palm swamps. Objective: To characterize the hydroperiod and physicochemical variables of water and soil and their effect on the distribution of vegetation in the Sistema de Humedales El Castaño. Methods: A total of 11 permanent sampling units (UM) were established by defined strata: five in the mangrove, two in swamp forest, two in freshwater marshes and two in the flooded pasture. From May 2016 to October 2017 the vegetation was characterized and the water levels and physicochemical parameters (superficial, interstitial and groundwater) were sampled monthly for: salinity, and pH; and the soil for: bulk density, humidity percentage, and redox potential. Results: Mangroves are the closest to the sea, have the lowest diversity (H: 1.66) and species richness (14), they are dominated by Laguncularia racemosa and Rhizophora mangle, have the highest values of interstitial and groundwater salinity, (> 10.8 ups), remain flooded for 4 to 12 months per year, and have a redox potential of 14.57 mV. Immediately, inland, there are remnants of the swamp forests (H: 2.18 and 18 species), dominated by Pachira aquatica, with 5 ups interstitial and groundwater salinity, flooded from 0 to 6 months per year, with a redox potential of 119.07 mV. These forests are followed inland by freshwater marshes (H: 1.92 and 16 species), dominated by Typha domingensis with 6.1 ups interstitial and groundwater salinity, flooded for 5 to 8 months per year and a redox potential of 125.9 mV. Finally, furthest inland is the flooded pasture, a modified herbaceous wetland for cattle grazing (H: 3.44 and 50 species) dominated by Paspalum conjugatum, where interstitial and groundwater salinity is less than 0.5 ups, it stays flooded for 5 to 9 months and the redox potential is 151.23 mV. Conclusions: In each type of vegetation, the structure, composition, and diversity are different, with a high turnover of species that indicates a gradient defined by salinity. The vegetation in the SHC follows the patterns of typical organization of the tropical coastal wetlands, mangroves, swamp forests and herbaceous wetlands, in this case the freshwater marshes and flooded pastures. The factor that define the distribution of the vegetation is the salinity and the gradient that is observed are a function of the hydrological dynamics that depends on the mixing of marine and freshwater. [ABSTRACT FROM AUTHOR]

Of the 6,5 million ha with hydro agricultural infrastructure in Mexico, 10% have problems with salinity and drainage. 16% of the 7,5 million hectaresof humid tropic with agricultural potential, has shallow phreatic table, floods and soil acidity. This problem in the areas of irrigation is increased by 10 000 ha/year with productive decrease of 25%. Since 1992, IMTA developedand transferred subsurface drainage technologies for the rehabilitation of saline in arid soils and management of the regime of soil moisture with lot controlled subsurface drainage in wet areas. Production increases of 20% to 93% in wheat were obtained with agricultural drainage and about 200% in sugar cane, thus economic and production indices have increased with this technology. [ABSTRACT FROM AUTHOR]

The regionalization studies of common bean genotypes are very important, having in to account the specific interaction between genotype and environment. The objective of this work was to determine the morphophysiological response of four commercial cultivars of common bean (Phaseolus vulgaris L.) in late planting season in two types of soil at Remedios municipality. The experiments were developed in La Granja Agropecuaria "Liberación de Remedios" whose soil is red ferralitic compacted and in the Agricultural Cooperative of Credits and Services "Celestino Gutiérrez" with a soft carbonated brown soil. The plant morphophysiological indicators evaluated were height. number of leafiets, leaf area, total fresh and dry mass. For the study an experimental random block design was used, consisting of four treatments (cultivars) and four replications. For each evaluation a random sample of 50 plants per plot was taken. All variables evaluated were significantly higher in soft carbonated brown soil. Notable differences were observed among soil types, mainly in the acidity of the soil, which could infiuence the morphophysiological response of the commercial cultivars studied. [ABSTRACT FROM AUTHOR]

The objective of this research was to characterize the mineral status of the soil and pasture in of the Andean Ecuadorian region, during the rainy and dry periods, three dairy farms were used as study cases investigated him three dairy farms of the El Carchi province. They determined the chemical indicators of the soil and the pasture, the descriptive statisticians were calculated themselves and It was used a multifactorial ANOVA to determine the main factors affecting them on them, comparing means with Bonferroni and Duncan test. The soil classified as acid lightly, 100 % of the samples presented elevated levels of organic matter, NH4+, Mg, Cu, Zn, Fe and Mn. The farm had a significant effect on the pH, Ca, Mg, K, Cu, Fe, Mg and P, and the climatic period on the organic matter, NH4+, S, Cu and P. Pasture presented deficiencies of Mg, Zn and Na, the other minerals were above the critical limits. The farm affected the Ca, P, Mg, Na and Mn, and the climatic period the levels of Ca, K, Cu y Zn. In conclusion, 100 % soil samples presented high OM, slight acidity, low levels of Ca and high concentrations of NH4+, S, Mg, Cu, Zn and Mn. In pastures, there were diagnosed deficiencies of P, Cu and Zn, and their concentrations differed among farms and the two climatic periods of the year. [ABSTRACT FROM AUTHOR]

Both soil phosphorus (P) and soil acidity are the key factors in soil fertility management and often limits crop production in subtropical agriculture. The objective of this study was to evaluate the response of lime and different P rates on sugarcane variety and their interactive effect on the sugar cane borer attack. A three factorial experiment containing, two sugarcane varieties i. e., (SP81-3250 and RB-956911); with and without application of agricultural lime (3.5 t ha-1) and four P rates i. e., (0, 20, 40 and 60 kg P2O5 ha-1) was carried out at the research field area of Federal University of Santa Maria, RS, Brazil during 2011-12. It assessed a) sugarcane stalk length, b) stem diameter; c) number of internodes, d) number of stalk ha-1, e) stalk yield, f) °Brix and g) Intensity of infestation Index. Results indicated that, the stalk yields of RB-956911 and SP81-3250 was 106.6 and 139.8 Mg ha-1, respectively. The °Brix was between 18.60% and 18.00%, respectively. The Intensity of infestation Index was 2.76% for the RB-956911 and 3.65% for the SP81-3250. The lime application showed significant results only on the borer attack. Phosphorus application increased the sugarcane yield from 105.9 Mg ha-1 to 136.5 Mg ha-1 with 60 kg of P2O5 ha-1. The application of phosphorus increased sugarcane productivity but it does not contribute which increase the borer attack. [ABSTRACT FROM AUTHOR]

In the procesing of the coffee of the Guamuhaya mountainous group large numbers of organic pollutants are generated. One of them is the pulp, which contains acid pH and high load of phenols and polyphenols that are toxic for most of the soil fauna. To give an efficient use to this compound is one of the main alternatives to this environmental problem. For that reason the objective of the present work was to determine the effect of the coffee pulp in proportion 3:1 on the structure of the soils Acrisol Alúmico Crómico (AAC), Cambisol Éutrico Húmico (CEH) y Cambisol Éutrico (CE) with different stages of sustainability. To complete the objective was calculated the distribution of the aggregations in the dry and humid sifters, the coefficients of structural stability and the index of average weight of aggregations considered by diameter. For the prosecution of the information was used the statistical program STATGRAPHICS Plus for Windows 5.1 and the factorial test ANOVA. Was obtained as main results that the coffee pulp can be used like a compound to improve the soil structure because it increase the aggregation of the soil fractions, principally the 5 and 3 mm, decrease the contents of dispersed particles less 0.25 mm and increase the average weight of each conglomerates useful for the agriculture. [ABSTRACT FROM AUTHOR]