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546,196 artículos
Año:
2020
ISSN:
2594-0252, 2448-7546
Tinal-Ortiz, Sofia; PALMA LÓPEZ, DAVID JESÚS; Zavala-Cruz, Joel; Salgado-García, Sergio; Palma-Cancino, David J.; Hidalgo-Moreno, Claudia I.
Colegio de Postgraduados
Resumen
Objective: To evaluate the chemical soil degradation caused by nutrients lost in Acrisols from the Savannah of Huimanguillo, Tabasco, Mexico.
Design/methodology/approach: The effect of two factors, land use and slope relief, were study. Properties evaluated were soil organic matter (SOM), total nitrogen (Nt), available phosphorus (P), Cation Exchange Capacity (CEC), and exchangeable cations (K, Ca, Mg, Na).
Results: The content of SOM were considerate rich to very rich, and did not showed any significant differences between factors. Nt was statistically high, and K was statistically low. P, CEC, Ca, Mg and Na showed statistically differences and lower contents.
Limitations of study/implications: Soil degradation is a global problem, therefore the necessity of studies to understand the effect of land use over soil fertility and land chemical conditions.
Findings/conclusions: The results indicates presence of chemical degradation in Acrisols, mostly by effect of land use and suggest the necessity of conservation strategies.
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Año:
2020
ISSN:
2594-0252, 2448-7546
Rivera-Hernández, Benigno; Garruña-Hernández, René; Santamaría Basulto, Felipe; Andrade-Torres, José L.; Carrillo-Ávila, Eugenio; Andueza-Noh, Rubén H.
Colegio de Postgraduados
Resumen
Objective: to evaluate the effect of three soil moisture tension (SMT) on lime yield and fruit quality in winter season.
Design/methodology/approach: Effect of three SMT (-10kPa, -35kPa and -85kPa) was studied. The variables evaluated were yield and quality attributes (size and color), taste (total soluble solids, titrated acidity and Brix/acidity ratio) and texture (fruit firmness and juice content).
Results: Yield and percentage of large fruits decrease as the SMT increases. No significant statistical difference was found between SMT of -10kPa and -35kPa in color variables, juice percentage, firmness and TSS, but were statistically different from the values found at -85kPa of SMT.
Limitations of study/implications: Although treatments that improve production and fruit quality were found, more studies are required to better understand the floral induction process in the winter season, as well as study the effect of SMT levels on the phenological stage of flowering.
Findings/conclusions: Results show that the highest production was achieved with the SMT of -10 kPa. Fruit yield decreased as SMT increased. Color, size, firmness and juice content of the fruit improved by reducing SMT.
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Año:
2020
ISSN:
2594-0252, 2448-7546
Aceves-Navarro, Lorenzo A.; Rivera-Hernández, Benigno; Santillán-Fernández, Alberto; Arrieta-Rivera, Agricola; Juárez-López, José F.; Gutiérrez-Burón, Roberto
Colegio de Postgraduados
Resumen
Objective: To define the actual best potential areas for growing coffee in Tabasco state and its expected potential yields. Also, define its new distribution in the year 2050 under a climatic change scenario, as well as the impact of this scenario on the future potential yields.
Design/methodology/approach: The FAO AgroEcological Zoning (AEZ) methodology was used to define the best areas to grow coffee and to estimate their potential yield in Tabasco state under current era and on a future climate change scenario for the year 2050 (FAO, 1981). The AEZ performed for the 2050 year takes in account a 1.6°C increment in the mean daily temperature for the selected climatic stations in the present study.
Results: The resulting overlapping map of soil and climate most suitable potential areas shows that in Tabasco coffee has been grown in not optimal agro ecological conditions. Actually the more suitable and optimal areas for arabic type coffee in Tabasco covers a 59,400.24 ha out of the existing total 2,034,227.52 ha.
Limitations of study/implications: There is a large group of new coffee clones in Mexico which leaf area and harvest index are unknown, getting hard to estimate their potential yields.
Findings/conclusions: In the year 2050, under the worst climatic change scenario, the actual best potential areas to grow coffee in Tabasco will be reduced in 96.42% and their potential yields will also be reduced in 67% compared to the actual potential yields.
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Año:
2020
ISSN:
2594-0252, 2448-7546
Chávez-Aguilar, Griselda; Burrola-Aguilar, Cristina; González-Morales, Azucena; Pérez-Suárez, Marlín
Colegio de Postgraduados
Resumen
Objective: to evaluate the effect of two forest species in soil organic carbon (SOC) stocks and ectomycorrhizal abundance (ECM) characterizing the most representative morphotypes ECM under each forest species.
Design/ methodology/ approach: SOC was determined by the oxide reduction method in soil samples collected at 0-30 cm under individuals of Pinus hartwegii and Abies religiosa. Ectomycorrhizal roots were extracted of soil to quantify ECM abundance and characterize the morphotypes ECM.
Results: COS under P. hartwegii (219.0 Mg ha-1) was not significantly different from that of A. religiosa (211.7 Mg ha-1), but not in the abundance of ECM, which was higher (p= 0.000) under A. religiosa (43.5%) than under P. hartwegii (26.4%). 21 total ECM morphotypes were observed, of which five were common under both forest species.
Limitations on study/ implications: it is an initial study that requires subsequent molecular identification of ectomycorrhizal morphotypes.
Findings/ conclusions: P. hartwegii and A. religiosa have the same capacity to storage COS under their individuals, while ECM abundance was defined by the forest species. Both forest species shared only 28% of total ECM morphotypes observed. This work contributes to knowledge as the first step for identifying the influence of the fungus-tree association on the dynamics of the COS in temperate forest soils.
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Año:
2020
ISSN:
2594-0252, 2448-7546
García-González, César G.; Porras-Flores, Damián A.; Arras-Vota , Ana M.; Prieto-Ampáran, Jesús A.; ORTEGA RODRIGUEZ, Anabel
Colegio de Postgraduados
Resumen
Objective: to analyze the evolution of pecan nut (Carya illinoinensis (Wangenh) Koch)production and its economic relevance in the State of Chihuahua, Mexico.Design/methodology/approach: in order to evaluate the evolution and behavior ofdifferent economic variables of pecan nut production, in Chihuahua, México, we appliedanalytical-synthetic and historical, and bibliographic and statistical techniques to studyindicators of planted, harvested and damaged area, value of production, yield per haand the Rural Average Price.Results: the need to add value to the fruit tree is highlighted, diversify itscommercialization, plan agriculture according to proper cropland uses and invest inagro-territorial development stands out.Limitations on study/implications: the growth of the planted area is taking placeconsiderably in the state, but it lacks agricultural planning.Findings/conclusions: consider the proper land use and the necessary conditions forthe long-term water sustainability of this crop. The State of Chihuahua has 75,238hectares (ha) planted with this tree crop, and annually it produces 92,938 t of nuts. It isthe largest nut producer in Mexico.
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Año:
2020
ISSN:
2594-0252, 2448-7546
Bucio Galindo, Adolfo; Castañeda Vazquez, Hugo; Izquierdo Reyes, Francisco
Colegio de Postgraduados
Resumen
Objective: Evaluate whether CMT values for bulk milk depend on its somatic cell content. Evaluate if the composition of the milk changes as a function of the number of somatic cells.Design/methodology/approach: 48 samples of bulk milk from different dairy farms and cheese factories in Tabasco, Mexico were taken randomly. Measured parameters were: California Mastitis Test (CMT), the somatic cell count (CCS), fat, protein, non-fat solids, lactose. The values of CCS were grouped in 3 intervals: (<500,000), (>500,000-1,000,000), (> 1,000,000) to be compared with qualitative data of CMT (0, 1, 2) in a two-way contingency table. Milk samples were also grouped in 4 categories according to their number of somatic cells A (0-250,000), B (>251,000-500,000), C (>500,000-750,000) y D (> 750,000) to compare fat, protein, non-fat solids, lactose by one-way ANOVA and Tukey test at a 5% confidence level.Results: The CMT values were dependent on its somatic cells content intervals; (x2 = 88.1, p < 0.05). A lower amount of non-fat solids, lactose and protein was observed in the group D, with highest category of somatic cells (p ?0.05). Limitations on study/implications: The CMT test depend on the somatic cell content in cow´s bulk milk. Milk with high somatic cell content had less non-fat solids, and less lactose. Findings/conclusions: The CMT have been traditionally used to assess the udder´s health of individual cows; in this research, we validate to use CMT to assess bulk milk samples. Samples with high somatic cell content had less non-fat solids, less lactose and less protein. That is important knowledge for cheese producers because high somatic cell content is linked to less cheese yield.
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Año:
2020
ISSN:
2594-0252, 2448-7546
Guerrero-Lagunes, Luz A.; Ruiz-Posadas, Lucero del Mar; Rodríguez-Mendoza, María de las N.; Soto-Hernández, Marcos
Colegio de Postgraduados
Resumen
Basil (Ocimum basilicum L.) is an aromatic plant whose fresh, dried leaves and essential oils are used in the manufacture of medicines, perfumes, food and beverage flavoring. Although worldwide consumption and production is increasing considerably, Mexico intensive cultivation of this species is emerging. From this perspective, this study raises, with the objective of evaluating the production of basil grown in hydroponic greenhouse under an open system using volcanic rock as substrate. D1, D2 and D3 (14, 28 and 71 plants m-2, respectively) and two concentrations Steiner nutrient solution (S1: 100% and S2: 50%) three planting densities were evaluated. A factorial arrangement 3x2 was used with four replicates per treatment. The results show that the highest values ??for plant height were presented with S1 D1 and D2; for fresh and dry weight of the aerial part were the treatments S1 D1, S1 and S2 D1 D2 which threw the higher S1 and D1 values ??greater leaf area was obtained. In the quantification of essential oils 14.03 mg was obtained essential oil, per gram of dry matter, the major component was linalool. The use of hydroponics with an increase in plant density, can generate up to 70.21 ton ha, increasing production by more than 600%, with the economic gains that this represents.
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Año:
2020
ISSN:
2594-0252, 2448-7546
Rivera-Lopez, Samuel; Perales-Salvador, Arturo; Del Valle-Sanchez, Manuel; Caamal-Cauich, Ignacio
Colegio de Postgraduados
Resumen
Objective: to analyze the variables of production and marketing of orange in the Mexican market.
Design/methodology/approach: was calculated the participation of the Mexican market in the world orange market, the exchange rate of the production variables of this citrus in Mexico, the trade balance of the crop in question, producer-export marketing margin, national and per capita apparent consumption and the index of revealed comparative advantages (RCA).
Results: Mexico owns about 8% of the world's harvested area of ??orange and produces 6% of the total volume of this citrus. The variation rate of the sown and harvested area of ??this crop was negative; the production volume presented a positive rate of 19.13%, attributable to the increase in the average yield per hectare. The commercial balance of the orange in Mexico had a positive balance in most of the years analyzed; in 2018, the United States of America (USA) consumed 91.33% of exports and provided 100% of Mexican imports of said citrus. Apparent consumption per capita has been greater than 35 kg. The producer's marketing margin with respect to the export price was 24.57%, while, with respect to the final consumer price, in the domestic market, it was 26.92%. The RCA with respect to the USA has been positive from 2014 to 2018.
Limitations on study/implications: the databases of international organizations present data with delays of up to two years. There is no repository of marketing margins calculated monthly by the Servicio de Información Agroalimentaria y Pesquera (SIAP).
Findings/conclusions: the orange producers are not the main beneficiaries of the value of national and international trade in this fruit. The Mexican market has a competitive advantage in the international orange market, the RCA is positive with respect to the USA; however, the volume of Mexican exports is low compared to production.
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Año:
2020
ISSN:
2594-0252, 2448-7546
Rocha-Méndez, C.; Chiquini-Medina, R. A.; Herrera Guzman, Carlos Josue
Colegio de Postgraduados
Resumen
The objective of this work was to compare the costs of the application of acaricides used in the control of Rhipicephalus microplus ticks, considering the necessary inputs for the application, the personnel involved and the indirect expenses generated in each treatment. The methodology consisted of applying different products Cypermethrin®, Azuntol®, Fluazuron®, Ivermectin®, and a parasitic fungus (Metarhizium anisopliae) to control the tick and identify the costs of the application. The highest cost per year of treatment per head of cattle corresponded to Fluazuron® with an amount of $1,282.50 per head of cattle, secondly Ivermectin® with a total of $1,053.45, followed by Metarhizium anisopliae with the amount of $279.00, Azuntol® with a total of $162.85 and finally Cypermethrin® $109.93. Although the use of the parasitic fungus was not the most economical, it offers environmental advantages over the other products.
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Año:
2020
ISSN:
2594-0252, 2448-7546
Martínez Aispuro, José Alfredo; Figueroa Velasco, José Luis; Sánchez-Torres, María Teresa; Cordero Mora, José Luis
Colegio de Postgraduados
Resumen
The purpose of this review is to know the mode of action and commercial application of unconventional plants as growth promoters in poultry production. Numerous reports have demonstrated the efficacy of plant phytochemicals as antioxidants, antimicrobial and immune-stimulants. Thus, the use of additives of natural origin in poultry feed represents a viable option to replace or reduce the use of antibiotics and growth promoters in broilers.
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