Agro Productividad

Nutritional evaluation of white corn grain for tortilla manufacturing

Jesús García-Pereyra — 2024-12-20

Objective: Agronomic characteristics such as density, hectoliter weight, grain hardness and nutritional value of maize (Zea mays L.) grain in terms of protein, starch and oil content were evaluated.

Design/Methodology/Approach: Using the Dickey John INSTALAB 700® equipment, hybrid and native maize grains from different commercial houses that are planted in Durango, central region of northern Mexico. The seeds evaluated were of the certified type and evaluated in the Agricultural Biology laboratory of the Technological Institute of the Guadiana Valley. The grains were prepared following CIMMYT laboratory protocols in order to evaluate the nutritional and industrial quality of maize.

indings/Conclusions: Ten genotypes exhibited soft grain hardness, one showed intermediate hardness and six showed hard hardness with values higher than a hectoliter weight of 74 kg hL-1, the latter having the greatest potential to be planted extensively for use in the production of tortilla dough.

Conclusions: The protein content in the corn evaluated was not statistically significant, but the starch content varied from 52 to 62% with an oil content of 3.5 to 6.9%.

Morphology, density and population fluctuation of new records of orthopterans associated with four agroecosystems

Francisco J. Avendaño-Gutiérrez — 2024-12-20

Objective: To determine orthopterans taxonomically, to calculate the population dynamics and fluctuation based on collections carried out in four agroecosystems in the Experimental Unit of the “Presidente Juárez” Agrobiology School in Uruapan, Michoacán, Mexico.

Design/methodology/approach: The research was conducted from August to December 2019. The agroecosystem was divided into four sectors, and for each sector a hectare of land with different crops was assigned. A completely randomized experimental design was established, with four treatments and five repetitions. Five collections were made in each sector, every 14 days. The field information was analyzed with the SAS software ver. 3.8, with Tukey’s means comparison test (0.05).

Results: Two thousand hits were carried out with an entomological net and 2024 orthopterans were collected. The outstanding genera and species were: Schistocerca nitens, Sphenarium purpurascens and Achurum sumichrasti.

Limitations on study/implications: Only five months of the year were evaluated, so the species determined can vary in their relative abundance.

Findings/conclusions: New records were found in seven families, 19 genera and 16 species: Acanthorintes tauriformis, Achurum sumichrasti (Saussure, 1861); Aidemona azteca (Saussure, 1861); Arphia conspersa Scudder, 1875; Brachystola mexicana Bruner, 1906; Ceuthophilus pallidipes Tomás, 1872; Conocephalus cinereus Thunberg, 1815; Dichromorpha prominula (Bruner, 1904); Ducetia japónica (Thunberg, 1815); Gryllus spp., Linnaeus, 1758; Melanoplus differentialis (Thomas, 1865); Neoconocephalus triops (Linnaeus, 1758); Rhammatocerus viatorius (Saussure, 1861); Schistocerca nitens (Thunberg, 1815); Sphenarium purpurascens (Charpentier, 1841); Stilpnochlora azteca (Saussure, 1859); Taeniopoda stali Bruner, 1907; Pyrgocorypha spp., Stal 1873; and Stenopelmatus spp., Burmeister, 1838.

Analysis of the agrifood situation in an elementary school community

Marisel Lemos-Figueroa — 2024-12-20

Objective: To analyze the agrifood situation (nutritional state) of elementary school children from the San Miguel El Piñón community, located in Españita, Tlaxcala, Mexico. The objective was to identify elements that could be used to design and implement strategies aimed to improve food and nutrition security in this rural area.

Design/Methodology/Approach: A participatory action research was conducted to analyze the information collected from mothers and children (n=44) from an elementary school located in San Miguel El Piñón, Tlaxcala.

Results: Based on their weight, size, and nutritional state, 69.6% of the participating children have a healthy weight. However, 26.1% of the participating children have symptoms of malnutrition, while no data was recorded for 4.3% of the children. Food insecurity was identified in the community as a consequence of which families cannot have a well-balanced diet.

Study Limitations/Implications: The results are only valid for the selected sample. Although the situation was studied in the field, the actual sample was small. Nevertheless, the national trend on this subject was confirmed.

Findings/Conclusions: This is a worrisome situation that can impact the physical, psychosocial, and cognitive growth and development of children. The sample evaluation revealed symptoms of malnutrition.

Pitahaya (Hylocereus undatus [Haworth] Britton & Rose) marketing margins for its sustainable development in Belize

Blanca I. Sánchez Toledano — 2024-12-20

Objective: To determine the marketing margins and direct participation of producers in Belize aimed to support the sustainable development of pitahaya.

Design/Methodology/Approach: The information was collected between October and December 2022, implementing participatory workshops with producers and members of the pitahaya production chain in the Cayo and Orange Walk districts, Belize.

Results: The producer and the consumer (90%) are the main participating agents of the pitahaya marketing process. The gross marketing margin amounted to 40%, which indicated that, for every dollar paid by pitahaya consumers, 40 cents went to the intermediaries, while 60 cents went to the producers.

Study Limitations/Implications: An in-depth market analysis should be carried out.

Findings/Conclusions: Pitahaya cultivation is just starting in Belize. Nevertheless, the country’s climate provides it with a high potential for success. The main marketing channel is made up of the producer and the final consumer. Belizean producers obtained 60% of the total price paid by the final consumer.

Spatio-temporal analysis of scientific research on models to estimate water balance in hydrographic basinsV

Alfredo Salinas-Castro — 2024-12-20

Objective: To identify in the world the main models or tools used to evaluate changes in water regulation,
through a bibliometric review in the especialized in scientific information, Scopus database, in order to know
the main variables evaluated that affect the hydrological regime of the basins.
Design/methodology/approach: With the help of bibliometric techniques, scientific articles available until
December 2022 in the Scopus database were collected using the SUBJAREA (envi) TITLE-ABS-KEY (“water
balance” AND “land use”) AND (LIMIT-TO (OA, “all”)) AND (LIMIT-TO (DOCTYPE, “ar”)).
Results: 407 scientific articles were collected from 1965 to 2022, this scientific production shows an exponential
growing trend that was concentrated above all in countries with agricultural traditions such as the United
States (89 publications), China (33), Germany (28), the United Kingdom (25) and Australia (21).
Limitations on study/implications: Most of the research was developed on topics associated with land use
change (82 texts), climate change (48), hydrological processes (44), subsoil water (34) and evapotranspiration
calculation (33). The most recurrent models for calculating the water balance were the Direct Water Balance
(230 texts) and the Soil and Water Assessment Tool (83).
Findings/conclusions: No research development was found in Latin American and African countries, so
these results can help redirect efforts in the research centers of these countries, with the aim of generating new
knowledge that helps make decisions about how to improve the efficient use of water in the face of climate
change scenarios and dynamics of land use change

Impact of Treated Wastewater Use on Heavy Metal Accumulation in Soils and Sudan Grass Crops in the Mexicali Valley

Jesús A. Jiménez-Angulo — 2024-12-20

This study investigated the impact of using treated wastewater on the accumulation of heavy metals in soils and sudan grass crops. The transfer rate of heavy metals from soil to Sudan grass was determined. The Sudan crop was established in two plots: one irrigated with fresh water from the Colorado River and the other with treated wastewater from the Las Arenitas treatment plant. Metals Pb, Cr, Cd, Ni, and Cu were evaluated at two soil depths. Results showed that the concentration of metals in the treated wastewater is higher than in freshwater but within permissible limits. At a depth of 0-30 cm, the concentrations (mg/kg) of Pb, Cr, Cd, Ni, and Cu in soils irrigated with fresh and treated wastewater were 24.59, 19.25, 0.61, 25.33, 26.70, and 31.78, 20.10, 28.31, 28.33, respectively. These values show significant differences in the concentration of Pb and Cd. Analysis of metals in the Sudan grass showed similar results for soils irrigated with both types of water, with Pb and Cd not detected. The transfer rate was less than one for all metals. These results indicate no contamination or toxicity risks when using treated wastewater in Sudan grass crops. However, continuous monitoring is necessary to prevent contamination risks. These findings provide a scientific basis for developing policies and strategies for sustainable water resource management in arid and semi-arid regions.

Rodents in Xerophilous Shrubland and Semi-Desert Grassland Communities of Southeastern Coahuila, Mexico

Erika Jasmin Cruz-Bazan — 2024-12-20

Objective: To assess the diversity of rodent communities in semi-desert grasslands and xerophilous shrubland at the "Los Ángeles" Ranch in southeastern Coahuila.

Design/methodology/approach: Monthly samplings were carried out from May to November 2020 using Sherman traps. The capture-recapture method was used to estimate species richness and abundance. Non-parametric estimators, species rarefaction curves, and rank abundance plots were utilized to measure species diversity. The Whittaker index was employed to assess species turnover between sampled communities.

Results: A total of 205 individuals from three families and eight species of rodents were recorded, with the Cricetidae family being the best represented. The species rarefaction curve showed that the shrubland exhibited greater diversity compared to the grassland. The dominant species were Onychomys arenicola in the semi-desert grassland and Peromyscus zamorae in the xerophilous shrubland.

Limitations/implications: There remains a need to extend long-term monitoring efforts to detect how anthropogenic activities influence species composition.

Findings/conclusions: The study highlights the importance of grasslands for the conservation of rodents in the state. Semi-desert grasslands and shrublands provide natural resources that should be preserved to maintain biodiversity in semi-arid ecosystems

Dynamic stochastic model of allometric equations and cumulative distribution for biomass-carbon in Pinus hartwegii Lindl., facing climate change

Moisés Arreguín-Sámano — 2024-12-20

Objective: to construct a dynamic stochastic model with validated biospheric-interaction, estimating allometric equations for the total volumetric increase and cumulative distribution of biomass for Pinus hartwegii Lindl in the states of Mexico and Puebla, considering climate change.

Design/ Methodology/ Approach: the methodology included the use of SiBiFor numerical databases, NASA Power data, Ordinary Least Squares mathematical models, the Random-Forest software, Ridge model with regression, R algorithms and Newton volumetric estimation equations.

Results: estimated allometric equations were obtained for the total volume of trees in 2023, highlighting the importance of linear regression models and the validity of the variables used. Newton's mathematical equations and theoretical models for excurrent tree-form types were found to have the best accuracy in estimating the total volume of the barked tree.

Limitations of the study/ Implications: this study has limitations in terms of generalization to other forest types and the availability of data in Mexico. However, it highlights the importance of understanding forest responses to environmental changes and the need for validated dynamic stochastic models to estimate allometric equations and assess carbon sequestration.

Findings/ Conclusions: this study highlights the importance of understanding and assessing the carbon storage capacity of forests, especially in the context of climate change. In addition, it underlines the usefulness of linear regression models and variable validation to estimate carbon sequestration in Pinus hartwegii forests.

Traditional knowledge in an agroforestry system and perspectives about agroecological practices in Nahua communities

Isela Violeta Valdés Alcántara — 2024-12-20

ABSTRACT
Objective: To identify traditional knowledge associated to the traditional agroforestry system (TAFS)
integrated by corn-coffee-allspice and to recognize perceptions and interests of Nahua communities towards
the incorporation of agroecological practices.
Design/methodology/approach: Work was done in two Nahua communities of Cuetzalan, Puebla, Mexico,
devoted to the production of corn (Zea mays L.), coffee (Coffea arabica L.) and allspice (Pimenta dioica Mill), in
TAFS. A qualitative research approach was used, in which semi-structured interviews were conducted.
Results: A representative population sample was interviewed; 74% of the population were women, 38% was
older than 65, 100% self-described as Nahua and recounted that maintenance of the TAFS is a family activity.
Performing soil and organic matter conservation was manifested by 29%; 26% described promoting the diversity
of species (cultivated and tolerated); 9% described establishing Scaptotrigona mexicana (endemic pollinator) in the
plot; 65% knows an agroecological practice, and of this portion, 42% would like to use organic fertilizers, 41%
considers that management of fertility and soil conservation are key to maintain the TAFS.
Limitations on study/implications: The findings reported are applicable to the context of Nahua
communities in the Sierra Norte region of Puebla.
Findings/conclusions: There are traditional understandings associated to the TAFS. These have an approach
of adaptation and emulation of local environmental characteristics to satisfy self-consumption. The approach
of integral management of the agroecosystem tends to sustainability. The perception of the incorporation
of agroecological practices is positive, and there is special interest in the management of soil fertility and
conservation.

Estrus syncrhonization in ewes with prostaglandins at dif-ferent days post CIDR insertion

Rubén Martínez-Cruz — 2024-12-20

Objective: To evaluate the effect of prostaglandin F_2α (PGF₂_α) application on days 0, 3 and 6 of the synchronized luteal phases on reproductive perfomance and its effect on progesterone concentrations of multiparous ewes.

Design/methodology/approach: The experimental design was a completely randomized. Seventy-five ewes synchronized with control internal drug release devices (CIDR) for six days and 250 UI of equine chorionic gonadotropin (eCG) were used at device removal. The ewes were randomly distributed in three treatments in relation to the days of application of PGF₂_α (125 μg sodium cloprostenol): in the first group of ewes, PGF₂_α was applied at the time of insertion of the CIDR (D0, n=25); in the second group PGF₂_α was applied on day three of insertion of the CIDR (D3, n=25) and in the third group it was applied on day six, at the time of the withdrawal of the CIDR (D3, n=25). The presentation of estrus and the gestation rate were analyzed through the c² test. The onset of estrus and prolificacy by a Tukey analysis of variance and comparison of means. The concentration of P₄ was carried out using the mixed design procedure, which included fixed effects of treatment and day, and interaction of both.

Results: Presentation and onset of estrus were different (P<0.05) between treatments due to the effect of the interval in the days of PGF_2α application. The progesterone (P₄) concentrations in blood serum showed differences during the synchronized luteal phase (D0: 4.8 ng mL^-1; D3: 6.0 ng mL^-1, D6: 8.8 ng mL^-1). However, no differences were found in gestation rate and prolificacy due to the main effects.

Limitations on study/implications: The application of 125 µg of PGF_2α on different days of the synchronized luteal phase does not affect gestation rate and prolificacy. Nevertheless, presentation and onset of estrus were different, so it must be considered in laparoscopic artificial insemination programs.

Findings/conclusions: The application of PGF_2αduring the synchronized luteal phase at short intervals showed better results at the end of treatment. The corpus luteum (CL) and CIDR increase P₄concentrations; which modifies the estrus response, and it has a positive effect in reproductive performance.

Potential Distribution Models for Predicting Human-Black Bear (Ursus americanus var. eremicus) Interactions in the Sierra de Zápaliname Natural Reserve, Saltillo, Coahuila

Jonathan G. Escobar--Flores — 2024-12-20

Objetive:This research analyzed the interactions between humans and bears in the ejidos of the Sierra de Zápaliname Natural Reserve and the urban area of Saltillo, Coahuila, Mexico.

Design/Methodology/Approach: A database of approximately 481 georeferenced records of Human-Black Bear Interactions (IHO) for the year 2021 was used. Based on these records and their relationship with physiographic variables (slope, aspect, elevation, roughness) and environmental variables (normalized difference vegetation index and a humidity detection index), potential distribution models were developed using the support vector machine algorithm, which is characterized by the assumption of the Greenelian niche theory.

Results: Six potential distribution maps were generated, divided into two rainy and dry periods and three types of interaction: sightings, agricultural-livestock conflicts and captures.

Findings/Conclusions: In all models, a common pattern was found where the sites with the highest probability of IHO are places close to human settlements and areas where agriculture, livestock and landfill activities occur.

Registry of mermithid (Mermithidae) parasites of spittlebug nymphs (Hemiptera: Cercopidae) in sugarcane crops in Veracruz, Mexico

Pedro Fabián Grifaldo Alcántara — 2024-12-20

SObjective: To make known the presence of parasite mermithids of the spittlebug nymph in different sugarcane
localities of the state of Veracruz, Mexico.
Design/methodology/approach: The nematodes were collected in sugarcane soils after observation of the
emergence of the pest from the spittlebug nymphs (in situ), while some others were obtained after collecting
spittlebug nymphs in the field and the pest’s emergence in the laboratory. The death of the nematodes was
provoked with hot water (sterile distilled, 60 °C), and they were measured and stored in Eppendorf tubes of 1.5
mL in formaldehyde 4% and kept in refrigeration at 4 °C.
Results: This report is presented as evidence of pest mermithids that emerge from the spittlebug nymph host
in sugarcane crops in eight localities of the state of Veracruz. Although their identification at the species level
could not be done, the length of each mermithid found was recorded, as well as its relationship with the host.
Limitations on study/implications: When the presence of mermithids was verified and their location was
identified in diverse localities, the opportunity of continuing with the collection of specimens was justified and
their identification could be formally performed, as well as the implementation of biological control studies
with the use of these native nematodes; also, the exploration of their roles in the control of nymphs from the
sugarcane crop.
Findings/conclusions: The presence of mermithid parasites of spittlebug nymphs in the sugarcane crop in
eight localities in the mountainous region of Veracruz was verified in situ. Their emergence was classified
initially on nymphs of the spittlebug (Hemiptera: Cercopidae) that belong to the genera Aeneolamia and Prosapia

Comparison of the Export Competitiveness of Limes from Mexico, Colombia, Argentina, and Brazil to the European Union

Natividad Hernández-Mendoza — 2024-12-20

Objective: To determine the competitiveness in the world and in the European Union of the main Latin lime-producing countries through the calculation of the normalized revealed comparative advantage to generate a discussion around the use of the free trade agreement that the countries have with the European Union.

Design/Methodology/Approach: Official sources were used to obtain the information in the period from 2001 to 2021, the normalized revealed comparative advantage was calculated and the behavior in the global market and in the European Union was forecasted. The Prais-Wisten method was used for the correction of autocorrelation.

Results: Competitiveness was estimated through the Normalized Revealed Comparative Advantage Index, both globally and in the European Union, for the main Latin American limes producers.

Study limitations/implications: The limitation of the study was that it was only compared with Latin American countries, the study could expand its comparison with other regions of the world.

Findings/Conclusions: The main Latin American lime producers were compared using the NRCA. Mexico has maintained a competitive advantage since 2003, while Argentina lost it in 2004. Brazil became competitive in 2021, while Colombia is not. Argentina has the biggest advantage, although declining, and Brazil has surpassed Mexico since 2019. Projections show that Mexico and Brazil will continue to improve their competitiveness, while Argentina will reduce it. The concentration of production in Mexico is an opportunity for other regions with similar conditions to increase production and export to the European market. The proposed hypothesis is accepted

Induction of shoot development of Stevia rebaudiana Morita II by vitamins and cysteine

ÁNGEL VIRGILIO DOMÍNGUEZ MAY — 2024-12-20

Objective: The aim of this study was to evaluate the influence of B vitamins and cysteine on the formation and development of shoots in Stevia rebaudiana (S. rebaudiana) Morita II, without the addition of plant growth regulators.

Design/methodology/approach: The starting material consisted of nodal segments, subjected to eight different vitamin treatments. The results were analyzed using mean comparisons and Tukey's test to identify statistical differences.

Results: The most effective treatment was treatment number two, which yielded an average of 7.5 shoots per explant, demonstrating its efficiency for multiplication. For explant elongation, treatment five proved to be the most effective.

Limitations of the study/implications: This study aims to establish a multiplication protocol with enhanced efficiency; however, a limitation is the transferability of the results to temporary immersion bioreactors.

Findings/conclusions: Thiamine and cysteine are two organic compounds that induce multiple sprouting, while nicotinic acid and pyridoxine promote the elongation of Stevia explants. This research represents a significant step towards transferring this knowledge to grassroots technological enterprises.

Evaluation of Commercial Biostimulants at Three Planting Densities in Roselle (Hibiscus sabdariffa L.) Crop, Guerrero Variety

Candido Mendoza Pérez — 2024-12-20

Objective: The objective was to evaluate the physiological and productive response of roselle crop in the induction of three commercial biostimulants in three greenhouse planting densities.

Design/methodology/approach: The experiment consisted of three treatments and a control; T1 (high density) with Super Hormonal, T2 (low density) with Cito Xplosion, T3 (medium density) with Vitaminum Forte and Control (TES). The physiological variables evaluated were (plant height, stem diameter, number of branches, fresh and dry biomass), yield (fresh and dry weight of calyxes) and quality (titratable acidity, total soluble solids (°Brix), pH and electrical conductivity).

Results: plant heights of 168.3, 187.3, 219.5, 183.3 cm were obtained for T1, T2, T3 and control. For stem diameter, T2 was better with 2.9 cm, while T3 was better in number of branches. T2 presented a greater number of calyxes, however, the best yield was obtained in T1 with 25.9 t ha^-1 of fresh calyxes and 3.86 t ha^-1 of dry calyxes. The control was better with 10.1 in °Brix and 45.8 meq/100 g of titratable acidity, while the T1 was better in pH and electrical conductivity as quality parameters.

Limitations on study/implications: evaluate other biostimulants in other planting densities and modify the concentration of the nutrient solution to know the physiological and productive response of the plant.

Findings/conclusions: The use of biostimulants in combination with agronomic management and nutrition can substantially improve the yield and quality variables of dry calyxes.

Neltuma laevigata and its influence on soil fertility in the Valle del Mezquital, Hidalgo, Mexico

Hortencia Guarneros-Manoatl — 2024-12-20

Objective: The physicochemical characteristics of soil fertility, based on the influence of mesquite (Neltuma
laevigata) were evaluated in an agricultural community of Ixmiquilpan, Hidalgo, Mexico.
Design/Methodology/Approach: Based on NOM-021-SEMARNAT-2000, physical and chemical
parameters were evaluated. Nine samples were taken from each of the four sites with and without mesquite
(n=36). The relationship between soil fertility and the presence or absence of mesquite mesquite was determined
with a paired t- test (p<0.05).
Results: A significant difference in organic matter content was recorded. Humic substances and acids are
higher in soils with natural vegetation with mesquite than in soils with natural vegetation without mesquite.
Study Limitations/Implications: The study does not consider changes in microbiological biodiversity or the
influence of other plant species in organic matter content and humic substances.
Findings/Conclusions: Mesquite promotes soil fertility in the area; consequently, proposing management
strategies for this species is fundamental in the Valle del Mezquital.

Hydrolysis of chicken feathers for their use as a protein additive in cattle feed

Ángel Ivan Mieles-Solórzano — 2024-12-20

Objective: To evaluate diverse protein hydrolysis methods of chicken feathers meal on ruminal digestibility for its possible use in the elaboration of protein additives for animal consumption.

Design/Methodology/Approach: Four protein hydrolysis methods of chicken feathers meal were evaluated: thermal hydrolysis (TH), chemical hydrolysis (CH), acid-enzymatic hydrolysis (AH) and allkaline-enzymatic hydrolysis (BH). These methods were compared to chicken feathers meal without any treatment as a control into a completely randomized design.

Results: All hydrolysis methods reduced the protein content in feathers meal when compared to control (p<0.05). Crude protein contents were 97.3, 70, 74.1, 75.5 and 87.7 for Control, TH, CH, AH and BH, respectively. However, the highest value in digestibility was observed in CH (p<0.05); whereas the other methods showed digestibility values lower to 20% (p<0.05).

Implications: Given results show that CH provide higher contents of soluble and digestible protein, as well as higher hydrolysis.

Conclusion: These results demonstrate that chicken feathers meal hydrolyzed by chemical methods shows optimal conditions which makes it suitable for elaboration of protein additives to animal consumption

Production Analysis of Corn (Zea mays L.) in Agricultural District VII Valle de Bravo, State of MexicoV

Gabriela Berenice Vilchis Granados — 2024-12-20

Objective: Analyze corn production in Rural Development District (RDD) 7 “Valle de Bravo”, State of
Mexico, focusing on the relationship between yield and sown area, as well as identifying factors that may affect
this production.
Design/methodology/approach: Data from the Agri-Food and Fisheries Information System (SIAP) on
sown area, production, and yield of corn (2003-2021) were used. Additionally, questionnaires were provided
to RRD 7 producers. Statistical analyses were carried out with SPSS software and simple linear regression
models were applied to evaluate productivity and associated factors.
Results: Corn yield showed linear growth; however, the sown area decreased as farmers have dedicated
themselves to producing more profitable crops. Guaranteed prices per ton were deemed inadequate and high
input costs hindered agricultural production.
Limitations: Farmers faced challenges such as high production costs and limited access to financial resources.
Government programs offer some support for corn production; however, this is insufficient to address the
structural problems of the sector.
Conclusions: A comprehensive strategy is needed to address the systemic challenges facing the corn sector.
This includes measures to improve productivity, reduce production costs, ensure fair prices, promote crop
diversification and enhance access to resources and technologies that guarantee the long-term sustainability of
the agri-food sector.

Genetic Improvement of Miahuateco Chili (Capsicum annuum L.) (Solanaceae) through Gamma Radiation of 60Co

Humberto Rafael Bravo Delgado — 2024-12-20

Objective: To improve genetic attributes in Miahuateco chili (Capsicum annuum L.) through gamma irradiation
with 60Co.
Design/Methodology/Approach: Seeds were irradiated at doses of 0, 100, 200, and 300 Gy at the National
Institute of Nuclear Research. The evaluated variables were LD50, agronomic yield, plant height, polar and
equatorial diameters, percentage of aborted flowers, number of branches, and plant color, which were assessed
under a completely randomized design (4X4)=16 experimental units.
Results: The results indicate that the application of 200 Gy induces higher agronomic yield. The LD50 is
reached at 145 Gy. High doses of gamma irradiation caused a high percentage of aborted flowers, as well as
chlorosis in the plant.
Study Limitations/Implications: The seeds used in this project were landraces, which exhibited significant
heterogeneity that could have affected flowering and fruiting. However, this was not a substantial factor for
this project.
Findings/Conclusions: It is concluded that 200 Gy of gamma radiation from 60Co induces genetic variability
in the species, improving certain agronomic attributes of interest.

Changes in physicochemical and antioxidant properties over one year of Apis mellifera honey

Armando Arrieta González — 2024-12-20

Objective: Quantify the physicochemical and antioxidant properties of honey harvested in the four seasons of the year, to determine the variation in its quality with respect to official standards.

Design/methodology/approach: Honey samples were collected in the municipality of Tantoyuca, during the four seasons of the year, in the presence or absence of rain. For each sample, color, electrical conductivity, moisture, pH, free acidity, diastase activity, total reducing sugars, Brix degrees, caloric content, phenolic and total flavonoid content and antioxidant capacity were determined by the FRAP and ABTS assays.

Results: The Brix degrees and moisture were found within the limits accepted by NOM-004-SAG/GAN-2018 and CXS 12-1981 throughout the year, however, in the rainy period these variables were higher (82.1 °Brix and 19.6 g 100 g^-1). The FRAP and ABTS values showed variation depending on the absence or presence of rain. The highest antioxidant content occurred in the winter season (63.91 and 68.82 µmol TE 100 g^-1).

The results obtained are attributed to the geographical origin and the floral species present during the bees' foraging.

Limitations on study/implications: Climate change in the region has decreased rainfall, reducing the floristic resource.

Findings/conclusions: The effect of the season of the year affects the characteristics of the honey evaluated, however, it complies with the parameters established in the Mexican standard and the codex alimentarius, which can encourage and support its commercialization in the international market.

Non-toxic Jatropha curcas L. residual paste as a protein supplement in poultry diets

Leonardo Díaz Sánchez — 2024-12-20

Objective: To evaluate the effect of the non-toxic residual meal from Mexican jatropha (Jatropha curcas L.) as
part of a protein supplement in broiler chicken feed.
Design/methodology/approach: An experimental diet was designed by incorporating meal obtained from
the non-toxic residual jatropha paste, which was administered to a group of 20 one-day-old Cobb 550 chicks.
The chicks were weighed every three days, and their feed was adjusted weekly according to their development
over a 28-day period. Another group of chicks, with the same number of individuals, characteristics, and
follow-up, was fed a commercial diet for comparison purposes.
Results: The inclusion of non-toxic residual jatropha paste in the broiler chickens’ diet produced similar
performance to that obtained with the commercial diet.
Study limitations/implications: The scale of the experiment could affect the generalization of the results to
a larger poultry population.
Findings/conclusions: The non-toxic residual meal from Mexican jatropha could be a viable and sustainable
alternative for enriching poultry diets.

Effect of meta-Topolin on the in vitro Propagation of Strawberry (Fragaria x ananassa Duch)

Jorge D. Cadena-Zamudio — 2024-12-20

Objective: Strawberry cultivation (Fragaria sp.) is globally relevant due to the appeal of its fruit and its organoleptic characteristics, which increase its demand. However, it is necessary to implement new propagation methods that allow the establishment of commercial plantations, such as plant micropropagation, in order to obtain thousands of plants in a reduced period of time. Therefore, the objective of this study was to determine the effect of meta-Topolin (mT) during the in vitro multiplication of strawberries.

Design/Methodology/Approach: In vitro strawberry plants were used in MS medium with 30 g L^-1 of sucrose, evaluating concentrations of meta-Topolin (mT: 0, 0.5, 1.0, 1.5 mg L^-1) and 6-benzylaminopurine (BAP: 0, 0.5, 1.0, 1.5 mg L^-1), under conditions of 24 ± 2 °C and a photoperiod of 16:8 h light/darkness.

Results: mT increased the number of shoots compared to BAP, with 1.0 mg/L yielding 4.72 shoots per explant and 1.5 mg/L yielding 3.50. At 1.5 mg/L, the shoots reached 3.41 cm. The roots formed during multiplication facilitated acclimatization.

Limitations/Implications: Although the use of meta-Topolin showed promising results in the in vitro multiplication of strawberries, its performance needs to be evaluated in later developmental stages, field growth, and response to different environmental conditions.

Findings/Conclusions: mT increased the number of shoots compared to BAP, with 1.0 mg L^-1 yielding 4.72 shoots per explant and 1.5 mg L^-1 yielding 3.50. At 1.5 mg L^-1, the shoots reached 3.41 cm. The roots formed during multiplication facilitated acclimatization.

New electrostatic theory for the ascent of sap in tall trees

E. Aceves-Navarro — 2024-12-20

Objective: to propose a new electrostatic theory for sap ascent in tall trees.
Design/Methodology/Approach: we accomplished a detailed review of the different theories published
regarding sap ascent by capillary in trees. The new theory proposed herein is based on some scientific studies
of physiologists, biophysicists, and other branches of science, which expose the scientific bases of the water
movement in the plant, but who have not proposed an integrated framework.
Results: the proposed theory analyzed prior knowledge, then based on it, a new explanation is proposed for
the ascent of sap in trees.
Study Limitations/Implications: no field experiments were carried out to verify the increase in sap ascent
in trees with heights greater than 40 m.
Findings/Conclusions: this new theory helps to better explain water loss through transpiration and metabolic
processes, since both are closely related to the water content in the mobile solution in conducting vessels.