Agro Productividad

Alimentary and anti-methanogenic potential of four tropical species in domestic ruminants

Eleab Silvano Beytia-Pacheco — 2023-05-19

OObjective: To describe some considerations about the alimentary and anti- methanogenic potential of Bauhinia divaricata, Dalbergia glabra, Piscidia piscipula and Caesalpinia vesicaria (Fabaceae) present in Campeche, Mexico, in domestic ruminants.
Design/methodology/approach: The information was obtained from databases and archives in the internet, as well as official pages of national and international organizations.
Results: Although there is vast information about some Fabaceae species, it is still limited for B. divaricata, D. glabra, P. piscipula and C. vesicaria, although they are consumed by domestic ruminants. The few studies available report between 11 and 18% of raw protein (RP) and some secondary metabolites; however, there are no
studies that allow understanding their anti-methanogenic potential and their effects on productivity.
Limitations on study/implications: This study offers a panorama of the alimentary and anti-methanogenic potential of four tropical species in domestic ruminants.
Findings/conclusions: B. divaricata, D. glabra, P. piscipula and C. vesicaria grow in the Yucatan Peninsula, they are found in grazing zones and are consumed by animals; however, there are few reports that determine the nutritional value of their edible components and no reports that evaluate their effect on productivity of domestic ruminants or their capacity to decrease the ruminal production of methane (CH ₄ ).

Diversity and relative abundance of rodent species under three habitat conditions in the Altiplano Potosino Oeste, Mexico

Jesús M. Martínez-Calderas — 2023-04-25

Objective: To evaluate the diversity and abundance of rodent species, as well as vegetation cover, under three habitat conditions in the Altiplano Potosino Oeste.

Design/Methodology/Approach: The work was carried out in eight sites with good (3), regular (2), and poor (3) vegetation cover conditions. Frequency, basal, and aerial cover data were collected in three plot sizes to obtain the results for the three types of vegetation: arborescent stratum (20×20 m), shrubs (3 plots of 5×5 m), and herbaceous stratum (2 plots of 1×1m). In order to collect the rodent data, three sampling nets with 100 Sherman traps were used. Rodent species diversity was determined using the Shannon-Whinner index (SWI), while abundance was obtained using the Relative Density Index (RDI). Differences were determined using ANOVA.

Results: Grass cover decreased depending on the condition; however, this was not the case of the shrub cover. The overall diversity of rodent species was 21 (16 in fair, 15 in good, and 14 in poor condition). The total SWI and RDI decreased depending on the condition. Dipodomys ornatus, D. merriami, and Chaetodipus nelsoni were the most abundant and most widespread species.

Study Limitations/Implications: The study was conducted during the most restrictive season and under drought conditions. This situation impacted cattle, but not rodents. However, although their plasticity maintained relatively stable RDI values, the indices decreased depending on the condition.

Findings/Conclusions: Despite their habitat conditions, the rodents found in the area are more diverse and abundant than those reported in reference works. Therefore, further studies about this subject should be carried out using rodents as bioindicators

Aphid diversity and population fluctuation of vector species of the ringspot virus in papaya (Carica papaya L.)

César Orlando Pozo Santiago — 2023-04-25

Objective: To examine the diversity of winged aphids in papaya (Carica papaya L.) crops and to determine the population fluctuation of vector species of the papaya ringspot virus (PRSV).

Design/Methodology/Approach: We captured winged aphids by placing eight Moericke-type water traps (four green and four yellow). We conducted weekly samplings to locate plants with ringspot symptoms, record the abundance of vector species of PRSV, and document the progress of the disease.

Results: We collected a total of n=694 individuals of 20 species, seven of which fell in the green traps and 19 in the yellow traps. The green traps registered the highest diversity value; however, the yellow traps captured the largest richness. Six of the captured aphids are reported as PRSV transmitters. The analysis of the population fluctuation of the vector species determined that A. spiraecola recorded two population peaks during the study: the first at week three, with 93 captured individuals; and the second (and highest) at week ten, with 316 individuals. PRSV was observed in the week seven in nine diseased plants. Full contagion (100%) was reached by week 44.

Study Limitations/Implications: Developing strategies for preventing and controlling pest species and disease vectors crucially depends on the correct choice of methods to capture and monitor insect populations in crops.

Findings/Conclusions: We can infer that vector species conduct short-distance migrations within the plantation. This inference is supported by the increased number of diseased plants.

Yield evaluation of rocoto pepper (Capsicum pubescens R and P) with application of calcium carbonate in greenhouses

Francisco Javier Piña Ramírez — 2023-04-25

Objective: To evaluate if the application of calcium carbonate on the soil and to the leaf influences the weight and number of fruits in rocoto pepper grown under greenhouse conditions.

Design/Methodology/Approach: The study was carried out in the greenhouse of the Facultad de Ciencias Agrotecnológicas, of the Universidad Autónoma de Chihuahua. The Taguchi method was used to develop the 13 treatments, with two factors, five levels per factor, and five repetitions per treatment, using 65 plants under study. Data was analyzed using the quadratic response surface technique, fitting the surface to determine factor levels for optimal response.

Results: Reducing soil CaCO₃ by 9% and increasing leaf CaCO₃ by 100% was necessary to obtain the highest weight in the three harvests (234.8 g).

Findings/Conclusions: A rise in the number of rocoto peppers (from 59 to 70, in the three harvest periods) required an increase in the soil and foliar CaCO₃ by 8.5% and 100%, respectively.

Interaction between nitrogen doses and alfalfa (Medicago sativa L.) incorporation in lettuce (Lactuca sativa L.) production

Juan Manuel Pérez Gómez — 2023-04-25

Objective: To determine the optimal nitrogen dose combined with alfalfa in the growth, yield, and ion concentration in the sap of the lettuce leaf.

Design/Methodology/Approach: We used a completely randomized experimental design, with a 2×5 factorial arrangement and nine repetitions in each treatment. The treatments consisted of five nitrogen doses (200, 250, 300, 350, and 400 kg ha^-1) and two soil conditions (with and without alfalfa).

Results: Aerial fresh weight (AFW), aerial dry weight (ADW), end-to-end diameter of the shoot (EDS), maximum diameter of the shoot (MDS), shoot weight (SW), and yield were higher when a 200-300 kg ha^-1dose of N was applied along with alfalfa. This application had a similar effect to the 300 kg dose of N ha^-1, applied without the addition of alfalfa. The concentration of nitrates (NO₃^-) in the sap decreased with the addition of alfalfa and 200 kg of N ha^-1. The concentration of potassium (K⁺) was higher with or without the addition of alfalfa and 250 kg of N ha^{- 1}. The concentration of calcium (Ca²⁺) was higher in the plants that received a 400-kg dose of N ha^-1, whether alfalfa was included or not.

Study Limitations/Implications: The lack of equipment prevented the determination of the nitrogen available in the soil.

Findings/Conclusions: The incorporation of alfalfa into the soil is a good alternative to improve lettuce production and reduce the use of nitrogen fertilizers.

Effect of climatic factors on the diversity and abundance of Scolytinae and Platypodinae (Coleoptera: Curculionidae) in a pine-oak forest

Maurilio Lopez Ortega — 2023-04-25

Objective: The aim of this work was to evaluate the diversity and abundance of bark beetles and ambrosial beetles and their relationship with temperature and relative humidity.

Design/methodology/approach: The study was carried out in a pine-oak forest of the northeastern Sierra of the state of Puebla, where a monitoring system was established using Lindgren traps baited with frontalin, brevicomine, alpha-pinene and beta-pinene.

Results: The presence of 23 species of bark beetles and ambrosial beetles was recorded. Gnathotrichus sulcatus (LeConte) and Pseudips mexicanus (Hopkins) were the most abundant species and their presence was significantly associated with places having high relative humidity.

Limitations on study/implications: The results obtained are limited to the studied ecosystem.

Findings/conclusions: It was concluded that the abundance of the species observed was closely related with climatic factors.

Resultados: Se registró la presencia de 23 especies de escarabajos descort

Productive potential and typology of the bean agroecosystem in the Papaloapan basin, Mexico

Roberto de Jesús López Escudero — 2023-04-25

Objective: analyze the municipal level production potential using simulation methods and typification of the bean agroecosystem based on the edaphoclimatic, socioeconomic, and technological characteristics present in the basin.

Design/methodology/approach: the potential yield of beans was mapped, the SWAT model set a total of 8423 HRU'S within the basin surface. Based on this, three clusters were generated for high (1-65-2.75 t ha^-1), medium (0.87-1.64 t ha^-1), and low (0-01-0.86 t ha^-1) yield.

Results: regarding the variables used to analyze the typology of clusters of the bean agroecosystem, Natural Resources (RN) had a P = 6.842e-08 value; Technological Development (DT) a P = 1.01e-06 value and Infrastructure Development (DI) a P = 8.284e-06 value, while the Economic Development (DE) variable obtained a value of P = 0.3564 and the Social Development variable (SD) a P = 0.04867 value, therefore, in these last two, there were no significant differences among the three clusters.

According to the P values, the high cluster agroecosystem presents the ideal conditions to produce comapa black beans, while the medium cluster can be improved to optimize it. For its part, the low cluster must be addressed in the RN, DT, and DI variables to improve its potential and sustainability.

Findings/conclusions: High cluster areas, despite containing fewer municipalities, present a higher production biophysical potential (RN). The agroecosystem of the high and medium-yield clusters has a surface with edaphoclimatic, socioeconomic, and technological characteristics suitable for the productive development of the bean agroecosystem.

Varietal description of two genotypes of manzano chili pepper (Capsicum pubescens Ruiz & Pav.)

Chirstiam I Galvez-Orduña — 2023-05-08

Objective: The objective of this research study was to obtain the varietal description of two varieties of manzano chili pepper in Las Montañas region, in central Veracruz, Mexico.

Design/methodology/approach: The varietal characterization module was established under greenhouse conditions. The markers recorded were in accordance with the International Plant Genetic Resources Institute for Capsicum and the Graphic Handbook for Variety Description of manzano chili pepper. The plants were characterized from seedling in greenhouse to adult plant. The agronomic management of the crop was carried out in accordance with the manual for the production of manzano chili pepper in Las Montañas, state of Veracruz.

Results: All qualitative markers were constant for the two varieties, MEXUVNE1-15-C2 and MEXUVCU1-16-C2, from seedling to fruit setting. In contrast, there were dissimilarities in plant height, and stem, leaf, flower, fruit and seed dimensions.

Study limitations/implications: The pandemic caused by COVID-19 was the main limitation, resulting in some markers not being recorded in a timely manner as indicated in the Graphic Handbook.

Findings/conclusions: Both varieties are very similar; however, the greatest distinction was in the quantitative markers, such as: plant height, fruit length, fruit diameter and number of seeds.

Family patio agroecosystem: role and empowerment of rural women in two communities

Leydy Odeth Ruiz Puente — 2023-05-08

Objective: To identify the role of women in the family patio agroecosystem and its relationship in the empowerment process, in two groups of women in the municipality of Medellín de Bravo, Veracruz, Mexico.

Design/methodology/approach: The research carried out is qualitative-quantitative, of a constructionist nature, and is based on the Research-Action-Participatory process, through adaptation of the management model for natural resource management in family farming.

Results: The psychometric results obtained in the Rosemberg Self-Esteem Scale indicate that the average response is 26.3, which indicates a normal self-esteem of women who work in the family patio agroecosystem, and positively impacts their human development, empowerment, and personal identity.

Limitations on study/implications: The work of rural women in the family patio agroecosystem is not recognized, so it is important that it be made visible, mainly to them, and that they be empowered in their being, through their actions.

Findings/conclusions: A total of 52 species were found, distributed among 15 fruit trees, 13 ornamental plants, 9 seasoning plants, 9 medicinal plants, 4 timber trees and only 2 vegetables. In the breeding of small species, 3 animal species are reported: 41 chickens, 2 pigs and 3 sheep.

Use of Theory of Change (ToC) as a methodological apprach to evaluate the papaya Maradol Regional Development Program in the Mixteca Poblana region

José Manuel De León Reyes — 2023-05-08

Objective: To determine the extent to which the use of the Theory of Change (ToC) as a methodological approach is appropriate to assess the medium and long term effects generated by the Maradol Papaya Program in the Mixteca Poblana region (Puebla, Mexico).

Design/methodology/approximation: A case study was conducted with qualitative approach with a phenomenological approximation directed at the validation of the ToC as methodological tool for the assessment of programs, through Documental Research methods, observation and interviews with producers and key informants for the study.

Results: The design of the route or pathway of change allowed a punctual definition of the key variables for its operation and measurement as part of the assessment exercise. The use of qualitative methods (in-depth interviews) allowed an appropriate valuation of qualitative variables, such as learning, identificaiton of quantitative variables (production volumes, production costs, etc.) that can be made with conventional methods (questionnaires) without this representing any methodological conflict.

Limitations on the study/implications: Since it is a case study, its generalization is not appropriate. However, there are elements that can be suggested as a general premise, such as the recommendation of the use of mixed methods in the assessment of programs and projects.

Findings/conclusions: The Theory of Change (ToC) is a valuable tool in identifying change variables through the design of the route or pathway change; however, this exercise has great validity and wealth if it is constructed in a participative way. The use of mixed methods (quantitative and qualitative) is suggested for this type of assessment.

PCR molecular identification of the fall armyworm in the Chontalpa region, Tabasco, Mexico

Eder Ramos-Hernández — 2023-05-08

Objective: To perform the first molecular characterization of the barcoding COI region of the S. frugiperda found in Tabasco and to test whether it can reliably identify the strain detected in the said state.

Design/Methodology/Approach: We collected S. frugiperda specimens using four pheromone traps placed in corn plots. Subsequently, we implemented DNA extraction, PCR with LCO-L/HCO-L primers, and the sequencing of six individuals captured in the traps.

Results: After aligning the sequences, we developed a phylogenetic tree, determining that S. frugiperda belongs to the rice strain (RS).

Implications: Identifying the S. frugiperda strain is necessary for management purposes, since different strains may require different control methods.

Findings/Conclusions: Our study revealed that the isolates from Chontalpa, Tabasco, Mexico, match the RS fall armyworm reported in other latitudes. Consequently, this is the first report to identify this strain of S. frugiperda in Tabasco. Our findings are relevant because this species can potentially become a pest in sugarcane- and rice-growing areas of the state.

Use of equine chorionic gonadotropin (eCG) in Mashona heifers, under a J-Synch synchronization protocol, and its effect in pregnancy rate

Fernando Sánchez Dávila — 2023-05-08

Objective: To evaluate the J-Synch protocol with two eCG doses in beef heifers during the summer in northeastern Mexico.

Design/Methodology/Approach: 218 heifers (109/treatment) with a body weight of 350 ± 12.1 kg were used. A J-Synch protocol was applied in order to evaluate two eCG doses: T1 (250 IU) and T2 (300 IU). Subsequently, the total number of heifers from both treatments were inseminated at a fixed time (FTAI): 72 h after removing the device.

Results: No significant differences (p>0.05) were recorded in the estrous percentage at first service (T1 = 91%; T2 = 96%) and in the repeating heifers (T1 = 25.2%; T2 = 19.2%). The insemination technician and coat color variables impacted the estrous percentage in repeating heifers. The pregnancy percentage at first service was 64.8% and 70.1% for T1 and T2 (p>0.05), respectively. The insemination technician had a variable effect on the pregnancy percentage, from 63.4% (the best-qualified technician) to 48.6% (the technician who obtained the lowest percentage).

Study Limitations/Implications: The pregnancy rate in beef heifers will depend mainly on the experience and skill of the insemination technician.

Findings/Conclusions: The same results were obtained regarding the presence of estrous and pregnancy in beef heifers during the summer season, either with 250 or 300 IU of eCG.

Corn price volatility and producer income protection

MARIO IVAN GARCÍA HERNÁNDEZ — 2023-05-08

Objective: To estimate the risk indicator of the future price of yellow corn #2 at the Chicago Futures Exchange (USA) regarding the spot price of white corn in the main producing regions in Mexico through the financial volatility indicator.

Methodology: The research used the returns of the monthly time series corresponding to the spot price of white corn from January 1998 to December 2020, considering five producer-consumer regions of Mexico and the future price of yellow corn #2 as listed on the Chicago Stock Exchange. To quantify volatility, the generalized autoregressive conditional heteroskedasticity model of order (1,1) was estimated.

Results: The yellow corn #2 volatility indicator was 0.9870 (future price). In the case of the spot price of white corn in Mexico, the volatility was 0.7977 for the national price, 0.3385 for the central region, 0.3206 for the western region, and 0.0078 for the southeast region.

Implications: The high volatility of yellow corn #2 (close to unity) shows that the international market for this commodity is riskier than the national market or regional markets in Mexico.

Conclusions: The national white corn market proved to be riskier than the west, center, and southeast regional markets, which have a higher volatility indicator.

Agronomic response of two experimental varieties of habanero chili in the application of band vermicomposting

Brenda L. Santiago-Morales — 2023-05-08

The habanero chili pepper has great productive potential in Mexico, with an annual growth of 12.5% in the planted area in the last five years. Objective: was to evaluate the agronomic response of two experimental varieties of habanero chili called HNC-6 orange color and HCC-8 chocolate color, belonging to the Center for Training and Development in Seed Technology. Methodology: the study was established under five doses of vermicompost, 0, 0.3, 0.6, 0.9 and 1.2 kg plant^-1 using a completely random design with a 2x5 factorial arrangement. Results: the HNC-6 variety had a better agronomic response than HCC-8, its yield was 95 % higher, the number of fruits per plant 84 %, fruit length (FL) 25 %, pericarp thickness 28 %, fruit firmness 11 %, and average fruit weight 4.7 %. The HCC-8 variety exceeded the height of HNC-6 by 38 % and the fruit diameter (FD) by 14 %. The vermicompost doses exerted a similar effect on both varieties. In conclusion, the experimental variety HNC-6 showed a better agronomic response under the conditions tested. The vermicompost doses exerted a response effect and similar trend in the two experimental varieties of habanero pepper tested, the significant interactions found in FL, FD, and total soluble solids indicate that the application of vermicompost influenced the quality of the fruits in some aspects. Conclusions: the main factors that determined the response of the crop are its genetic component in response to the environment and the degree of maturity of the vermicompost.

Soy (Glycine max L.) production and importation determinants in Mexico and actions aimed to increase its domestic coverage

Francisco Garcia-Fernández — 2023-05-12

Objective: To analyze soy (Glycine max L.) production and importation determinants in Mexico, during the 1990-2000 period.

Design/Methodology/Approach: Using lineal models, two econometric models were developed, in order to evaluate the relation between the soy production, harvested area, and soy production vs. importation variables.

Results: We confirmed that soy production in Mexico is related to the increase of the harvested area, which promotes an increase in the domestic market and a reorganization of the soy harvested areas. The second model verified that the importations are the result of the limited domestic production. We propose a set of actions to increase domestic soy production.

Study Limitations/Implications: The models must consider new variables to broaden the determinants and to improve the public policy actions proposed.

Findings/Conclusions: The low domestic coverage rate and the high dependency on imports requires the implementation of policy actions to improve the domestic production capacity. A specific set of actions is proposed.

Perception of inhabitants from the Laguna Santiaguillo Basin: natural resources and liveli-hoods

María del Socorro Morales de Casas — 2023-05-12

Objective: To learn about the state of the natural resources and productive systems in the Laguna Santiaguillo Basin from the viewpoint of the inhabitants.

Methodology: The approach was qualitative, by means of a focus group.

Results: The problems perceived are related to: access to water both because of its low availability and due to the inequity in its distribution which generates low productivity and conflicts over the use of this resource; low prices for agricultural products; conflicts arising from the use of wildlife; and the degradation of grasslands as a result of overgrazing.

Limitations on study/implications: The Mennonite group, which is an important actor within the basin, was not represented in the focus group.

Conclusions: The participants in the group perceive the basin’s problem in an integrated manner, linking components of natural, economic, social and political resources, which lead them to actions adapted to their context to solve this problem.

BIOACTIVE PEPTIDES IN RED MEATS, BYPRODUCTS AND RESIDUES FROM THE MEAT INDUSTRY

J. Olloqui Enrique — 2023-05-12

Objective: To provide a comprehensive overview of the generation of bioactive peptides from raw red meat, its by-products, and the waste meat cuts, as well as the bioactive health effects.

Design/methodology/approach: A literature search was conducted through the organization and systematized analysis of information for an updated literature review of bioactive peptides in red meat.

Results: Meat is a food of great nutritional value for human beings, since the digestibility of its protein stands out. In addition to the nutritional value of this protein, there are some studies in meat where bioactive peptides provide bioactivity mainly as an antihypertensive and antioxidant. Bioactive peptides are generally obtained by enzymatic hydrolysis and through microbial fermentation processes. Subsequently, they are identified by analytical techniques to perform in vitro and in vivo evaluations verifying the bioactivity of the peptides obtained.

Limitations on study/implications: The food industry must establish the most reliable methods for generating more reliable peptides to standardize their production and avoid process variability.

Findings/conclusions: The bioactive activity to be exerted by the peptides will depend on factors specific to the protein, such as the number of amino acids it contains, the hydrophilic or hydrophobic profile, and size, among others. This information is key to predict the activity the peptide can exert in the human body since many can have multiple activities, the most common being the antioxidant-antihypertensive function.

LD50 and GR50 estimation with gamma rays (60 Co) IN Arachis pintoi Var. amarillo

LUIS ANTONIO GALVEZ MARROQUIN — 2023-05-12

Objective: To estimate the median lethal dose (LD₅₀) and mean reductive dose (GR₅₀) due to gamma radiation in Arachis pintoi var. Amarillo seeds.

Design/methodology/approach: Ten doses were used (100, 200, 300, 400, 500, 600, 700, 800, 900 and 1000 Gy) plus a control (without radiation). The experimental design was completely random with three replications and 50 seeds per repetition. Seed germination was evaluated 29 days after sowing (das) and plant survival, plant height, root length and leaf area at 60 das. The LD₅₀ and GR₅₀ for survival and plants height were estimated by linear regression.

Results: There was a significant reduction of seed germination and plant survival from 300 and 200 Gy doses compared to the control (61.64 and 49.15 % each); for the plants height the dose was of 100 Gy (35.22 %). There were no differences in the root length and leaf area with 100 and 200 Gy regard to the control. The LD₅₀ was estimated at 212.54 Gy and the GR₅₀ at 162.16 Gy.

Findings/conclusions: The gamma radiation doses to induce genetic variation in A. pintoi var. Amarillo seeds were between 162 and 212 Gy.

Evaluation of the Genipa americana L. / Heliconia stricta Huber agroforestry system and its effects on soil fertility

JANNI SILVANO SANCHEZ — 2023-05-19

Objective: To evaluate the plant development of Genipa americana L. and Heliconia stricta Huber associated as an agroforestry system, and their effects on soil fertility.

Design/methodology/approach: A completely randomized experimental design with three replications per treatment was used. Genipa plantations were established in July 2019 and Heliconia in September 2020. Soil samples and analyses were carried out based on the methodologies specified in NOM-021-RECNAT-2000 (SEMARNAT, 2002). Monthly measurements of height, stem diameter, number of leaves, photosynthetic rate were made for Heliconia and Genipa, as well as number of branches and canopy cover for the latter. Means were compared by Tukey’s test at a 5% confidence level.

Results: Contents of organic material (OM), Phosphorus (P) and Manganese (Mn) in the soil did present significant differences because of the treatments, cultivated alone and/or associated, while the contents of Nitrogen (N), Potassium (K), Calcium (Ca), Magnesium (Mg), Zinc (Zn) and Copper (Cu) did not. The behavior and development of Genipa was the same in the treatments, while Heliconia did present variations.

Limitations on study /implications: It is recommended to continue the study.

Findings/conclusions: The treatments cultivated alone and/or associated improved the (OM) contents in the soil. Genipa is not affected by the effect of the treatments evaluated, while heliconias are.