Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

Background. Rural agri-food systems are responsible for the production of most of the food products consumed in urban centers, however, despite the current importance they have in the food systems of populations worldwide, their structure and functioning, both key aspects for understanding its sustainability, have not been studied enough. Objective. This study was aimed at describing the conditions associated to agri-food systems sustainability in rural communities based on the understanding of their structural and functional elements, through a systematic review of scientific literature. Methodology. A comprehensive search for original papers in three different databases, ScienceDirect, Scopus and PubMed, was carried out, filtering the results based on inclusion and exclusion criteria, and subsequently adding grey literature. Results. Our findings indicate that sustainability in these agri-food systems relies on socioecological interrelations, whose environmental and sociocultural aspects are more relevant than the principles of the market economy, which become a menace for these systems. One of our most relevant findings is the essential role of distribution networks for ensuring sustainability. Implications: It is necessary to assess the different categories defined in agri-food systems in order to define in indigenous and rural communities the adjustments they require to achieve sustainability. Conclusions. Rural agri-food systems behave as complex, adaptive systems, conditioned by the multiple factors and dimensions of their biophysical, sociocultural, and political environment, as well as by the role of gender in their functioning.

Background: Weeds are a common occurrence and challenge in different crops eventually influencing crop development and yields. Weed control and management are key in enhancing the productivity of cultivated pastures. In semi-arid Kenyan drylands, the main methods employed for weed management are manual cultural practices and recently, the application of commercial herbicides. Objective: To evaluate the effects of two weed control methods on weed characteristics and productivity of four rangeland grasses commonly used in reseeding and pasture improvement in a semi-arid environment. Methodology: In a randomized complete block design in a field experiment, we determined the effects of two weed control methods (manual and herbicide use) in four rangeland cultivated grasses. These are Buffel grass (Cenchrus ciliaris), Horsetail grass (Chloris roxburghiana), Masaai love grass (Eragrostis superba) and Bush rye (Enteropogon macrostachyus). Weed characteristics (species, density, diversity and weed biomass,) were evaluated, as well as the effectiveness of the weed control methods in the grasses. Results: Broad-leaved weeds and annual grasses were prevalent in the established grasses. Generally, higher grass dry matter yields were obtained in Cenchrus ciliaris grasses (2.05 t h-1) while lowest yields were in Chloris roxburghiana (1.2 ton ha-1). Weed management interventions increased biomass production in the grasses by a mean of 19% in general. The mean yield increase varied with species and weed control method ranging from 8-39%. Weed control methods significantly reduced weed density, diversity and eventually weed biomass within the grass species. The efficacy of manual weed control and chemical application was in the range of 27-74%.  Implications: Weed control is, therefore, necessary if one is to realize higher productivity and returns in cultivated pasture and fodder systems in semi-arid environments. Conclusion: Both chemical and manual control methods of weed control are important and effective approaches to manage weeds in pasture systems in semi-arid environments.

Background. The results of a review on the factors that affect nitrogen fixation in the Inga-café system are presented. The nitrogen contribution that the Inga Miller tree genus provides to shade coffee plantations and the factors that affect its stability in biological nitrogen fixation are scarcely recognized. This work delves into the ecological factors and glyphosate herbicides that can affect the symbiosis of Inga spp. with diazotrophic bacteria in their roots (rhizobia), which form nodules and carry out biological nitrogen fixation. Methodology. Different information sources such as EBSCO, Scopus and Google Schoolar were reviewed, with logical or Boolean data search. 183 papers were used to address the factors that affect the symbiosis between trees of the Inga genus and rhizobia. The findings were organized in: Inga Miller taxonomy, shade coffee plantations with Inga spp., symbiosis between Inga spp. and Bradyrhizobium spp., ecological factors that affect the functioning of the Inga spp.-rhizobia symbiosis and the agrochemical factor: glyphosate herbicide. Results. The genus Inga is recognized as a clade Mimosoideae nested in the subfamily Caesalpinioideae. Shade coffee plantations with Inga are established below 23º N and 30º S, up to 3,100 m.a.s.l. and the symbiont genus is predominantly Bradyrhizobium spp. whose ecological limits of Inga spp-rhizobia were: altitude [988.7-1,381.5 m.a.s.l.], annual precipitation [2,048.4-2,064.36 mm], temperature [20.39-21.93 ºC] and soil pH [4.88-5.42 pH]. Glyphosated herbicides, as an external stimulus, can reduce the benefit of biological nitrogen fixation and erode the soil by keeping it devoid of vegetation. Additionally, some Bradyrhizobium spp. (thiO gene), which oxidizes glyphosate to aminomethylphosphonic acid (AMPA), could be a potential glyphosate degrader in the soil. Implications. Shade coffee plantations with 205-250 trees per hectare of Inga spp. allow fixing around 45 kg of N ha-1 year-1. This review may allow the adoption of new observational or experimental studies of the Inga spp.-rhizobia symbiosis, to approach the performance that favors the biological fixation of nitrogen in shade coffee plantations. Conclusions. The review indicates that there is a specific association between Inga spp. and Bradyrhizobium spp., that ecological factors, including the agronomic management with glyphosated herbicides can decrease nitrogen fixation performance during the symbiosis between Inga spp. and rhizobia. No systematic studies of the symbiosis-environment-agrochemical interaction in shade coffee plantations were found.

Background. In West Africa, the eggplant crop participates in the fight against rural poverty, hunger and malnutrition due to their higher nutritional contents.  However, this crop is faced with several constraints including poor soils and low yielding cultivars. It is known that mycorhization of plants improves plant nutrition while preserving them from certain pests. Objective. To evaluate the combination of mycorhization and vermicompost effect on eggplant plants growth and yield. Methodology. A consortium of arbuscular mycorrhizal (AM) from forest soils was trapped using maize roots and used as inoculum for eggplant, Djamba F1 variety. A trial using this inoculum combined or not to vermicompost was carried out for 90 days under a greenhouse. Selected soil properties, eggplant growth and yield indicator were recorded at the end of trial. Results. As expected, soil vermicompost alone or combined to inoculum displayed an increase of soil parameter such as pH, exchangeable base cations, total organic matter, total nitrogen compared to control and soil with AM alone. Soil with AM alone had a limited impact on the growth and yield of eggplant. In contrast, all treatments including vermicompost (vermicompost alone and vermicompost + AM) showed a significant increase of eggplant growth parameters and yield’s indicators. Implications. These results highlighted a need to carry out a screening of mycorrhizal fungi from eggplant production areas to isolate and identify the efficient strains of mycorrhizal fungi for symbiosis with eggplant under tropical conditions. Conclusion. The vermicompost significantly improved the growth of the eggplant. Its coupling with a consortium of spores of the genera results in better plant growth and yield. This combination has a significant effect on the studied parameters (height, crown diameter, biomass and yield). 

Antecedentes: Veracruz es el segundo productor de café en México y su producción es de importancia productiva, económica y social.  Objetivo: analizar la participación de la mujer en el proceso productivo del café y la toma de decisiones en 11 municipios de la región de las Altas Montañas de Veracruz. Metodología: Se utilizó una encuesta aplicada mediante entrevistas personales, con la aplicación de 98 cuestionarios a mujeres productoras de café. Se trabajó con dos grupos focales: dueñas de cafetales definidas como Mujeres Productoras de Café (MDP, 15) y no dueñas de cafetales pero que participan en la producción familiar consideradas como Mujeres Familiares Productoras de Café (MFP, 18); se creó una base de datos en Excel Microsoft Windows, los datos fueron analizados con Statistica versión 8.0. Resultados: Se obtuvo que las MDP ejercen un doble rol (productoras y amas de casa/emprendedoras/artesanas), mientras que las MFP se dedican exclusivamente al hogar. Por tanto, aunado a que tengan los derechos sobre la propiedad de las tierras, su participación es baja. Implicaciones: es importante realizar la investigación con perspectiva de género para reconocer la actividad preponderante de la mujer, considerando a los hombres. Conclusiones: es importante fomentar en las mujeres que reconozcan sus labores para lograr visibilizar el trabajo ejercido en las parcelas.

Antecedentes. La problemática pesquera en el Sistema Lagunar de Alvarado (SLA), considerando los aspectos ambientales o socioeconómicos, ha sido analizada por diversos autores, pero muy poco se ha abordado la relación entre los problemas ambientales percibidos por los pescadores y la migración. Objetivo. Identificar el fenómeno migratorio en tres zonas del SLA y su relación con la problemática ambiental que perciben los pescadores. Metodología. Se aplicaron cuestionarios en 32 Unidades Pesqueras Familiares. Para cuantificar la problemática ambiental percibida y relacionarla con la migración, se utilizaron los indicadores: Contaminación Percibida por los pescadores, Estado de Salud Percibido del Recurso Pesquero y Estado de Salud Percibido del Medio Ambiente. Resultados. Las zonas de humedal presentan condiciones socioeconómicas más precarias que la que limita con tierra firme, mientras que la migración y la problemática ambiental percibida tienen un comportamiento distinto en cada zona. Implicaciones. Debido a que las causas de la migración son múltiples, el deterioro ambiental incide en este fenómeno, pero no lo explica por sí mismo, por tanto, se requieren análisis más integrales. Conclusión. No existen elementos suficientes para afirmar que el deterioro ambiental identificado por los pescadores sea una causante importante de la migración. 

Background: the agronomic yield of crops of importance for rural households in the humid tropics, such as banana, cultivated in association with leguminous trees, such as Inga spp., must be studied because of the little available information on that association, especially with regards to yield response to the application of P and K under agroforestry systems, and the interaction between organic (leguminous residues) and inorganic sources of nutrients. Objective: the objective of this study was to evaluate the yield of lady finger banana alley cropped with Inga spp., under several levels of natural fertilizers such as K2SO4 + Mg, and phosphoric rock (RF). Methodology: Yield response of lady finger banana (Musa acuminata Colla) under an alley cropping system with guama (Inga spp.). Prior to the establishment of the crop, dolomitic lime (Ca3(PO4)2CaF2) at a rate of 2 ton ha-1 was applied. In addition, phosphoric rock (RF) was added to the crop at diverse levels (0, 20, 40, 80 kg ha-1), and potassium sulphate and magnesium (K2SO4 + Mg) at three levels (0, 45, 90 kg ha-1) with five replicates in a total of 35 alleys for treatments. Inga spp. trees provided with nitrogen (N). Two crop cycles were evaluated, cycle 1 (2015) and cycle 2 (2017). Results: the highest average weight per bunch were obtained with 80 FP and 0 RF in the first cycle, and with 90 K and 45 K in the second cycle, which were significantly higher than other levels. The highest yield on yearly basis was 45 K among the treatments during the first cycle, and the highest yields during the second cycle were obtained with 45 y 90 K2SO4 + Mg. Implications: There are no prior studies for lady finger banana crop associated with Inga spp. trees under alley cropping, this reflects that the study is an original contribution to nutrient-response studies under agroforestry system with Inga. Conclusion: the highest yields were obtained with 90 and 45 kg ha-1 of potassium sulphate and magnesium. The application of dolomitic lime promoted P and K availability for the crop, and better use of applied K2SO4 + Mg and of RF in the treatments.

Background: The main problem in grapevine cultivation is root-attachment nematodes cause serious yield problems in most crops worldwide. Through their different infection mechanisms these nematodes synthesize and secrete a mixture of protein-based effectors that they use to penetrate the root, migrate and develop into giant root feeding cells in host plants. The use of new molecular tools such as MALDI TOF/TOF (Matrix-Assisted Laser Desorption/Ionization - Time-Of-Flight) mass spectrometry and PCR (Polymerase Chain Reaction) technique have allowed us to know these proteins and genes in different microorganisms. Objective: To characterize the root-knot nematode Meloidogyne javanica by sequencing the 18S rRNA gene from infected root samples and the effector proteins of juvenile (J2) and adult (J4) stage of M. javanica by MALDI TOF/TOF shotgun proteomics dual mass spectrometry. Methodology: Infected roots of grapevine crop were collected to extract fresh galls and J2 of M. javanica, then inoculated on tomato plants. J4 of M. javanica were used for genomic DNA extraction and sequencing at the 18S rRNA gene level. The J2 and J4 stages of M. javanica were disinfected with sodium hypochlorite (0.5%) and sterile distilled water for protein extraction and analysis with MALDI-TOF/TOF. Finally, the sequences obtained were processed with ProteinPilot™ and Protein BLAST software for the identification of effector proteins of M. javanica. Results: The nematode M. javanica was molecularly identified by PCR amplification of the 18S rDNA gene M. javanica with an identity percentage of 98% from infected root samples and by MALDI TOF/TOF mass spectrometry, effector protein sequences were identified such as: Beta-1,4-endoglucan and polygalaturonase, identified from J2, and expansin B2, CLAVATA3/ESR, Pectate lyase and Chorismato mutase from J4, involved in the different infection processes. In addition, we were able to identify 49 nematode non-effector proteins in both stages related to conserved biological development. Implications: The results indicate the existence of effector proteins related to root gill formation. Conclusions: This study confirms that dual mass spectrometry methodology provides in a rapid and reproducible way a proteomic profile that the galls nematode synthesizes to infect root cells and that can be used in other types of pathogens.

Background: The excess of antimicrobials and anthelmintics cause important dysbiosis processes in equines, as well as resistance phenomena mainly in the communities of bacteria, archaea, protozoa, and helminths. The study of the equine microbiome is becoming more and more relevant to understand the biotic processes of the gastrointestinal tract. In colon and cecum, the role of cyathostomins as part of the microbiome is still unexplored. While interaction with certain bacterial groups may be key to the understanding of parasitism. Objective: To characterize the microbiota in feces of yearling naturally infected with cyathostomins in a quarter-horse farm in Sierra de Lobos, Guanajuato, Mexico. Methodology: Weights were measured and obtained the parasite burden in feces, from which samples were transfer and processing in the laboratory for DNA extraction and later sent for sequencing and analysis. Results: Average weight of the colts was 399 kg, and the average weight of the fillies was 432 kg. All horses were high shedders:  1,390 ± 698 egg per gram of feces. Alpha and beta diversity analyses indicated no differences within the microbial community between colts and fillies. Main bacteria at Phyla in both groups (females; males) were Bacteroidetes (37%; 37%), Firmicutes (46%; 37%), Verrucomicrobia (4%; 10%), Spirochaetes 5%; 4%) and Proteobacteria (1%; 3%). At Class level the principal identified groups were Bacteroidia (31%; 31%), Clostridia (43%; 35%), at Order level are Bacteroidales (31%; 31%) and Clostridiales (43%; 35%). Main bacteria at Family level were Ruminococcaceae (19%; 11%), Lachnospiraceae (15%; 6%) and non-assigned family Bacteriodales (19%; 21%). The most abundant non-assigned bacterial Genra were Bacteroidales (26%; 27%), Ruminococcaceae (10%; 5%) y Lachnospiraceae (9%; 6%); the assigned bacterial Genra were Clostridium (5%; 9%) and Treponema (4% y 3%).  The most abundant non-assigned bacterial Species were Methanocorpusculaceae sp (19%; 22%), Pedobacter sp (10%; 5%), Bacteroidales sp (9% y 6%) and Prevotella sp (4% y 3%); the assigned bacterial species were Fibrobacter succinogenes (2%; 1%), Succinispira mobilis (1%; 1%).  Implications: It is suggested that environmental factors and feeding are aspects that regulate the parasitic burden and the bacterial composition in this studied population. This is a short communication of the finding of the components of the microbiota and is relevant in Mexico for future studies, however it is imperative to explore the composition of the metacommunity of a horse free of cyathostomines. Conclusion: Considering that these nematodes are in the cecum and colon, where this microbiota was inferred, and that it is not known whether this interaction is beneficial or detrimental, the study of the microbiome is imperative. In the study, no horse presented clinical signs or colic due to the presence of nematodes.

Background: Chrysanthemum is one of the most popular landscape plants worldwide. Introducing desirable traits into this plant by conventional breeding has limitations due to cross-incompatibility. An approach to this problem is the introduction of resistance or tolerance traits via plant genetic transformation. In vitro regeneration of plants is necessary for implementing genetic transformation systems; therefore, regeneration via morphogenesis is required before any genetic transformation attempt. Objective: To induce morphogenesis from the leaf explant of Dendranthema grandiflora var Micromargara. Methodology: Micropropagation from node cuttings was induced from node cuttings of 3 cm in length from 6 months-old plants that were used as explants to produce seedlings as source explants. Morphogenesis experiments were done using leaf segments of 1 cm2 from 8-weeks-old in vitro seedlings. The explants were transferred to basal medium Murashige and Skoog at 4.4 gL-1 supplemented with different plant growth regulators. During the morphogenic process, leaves samples were collected to detect which morphogenic process was induced. Results: Node cuttings culture on Murashige and Skoog medium at 3.3 gL-1 supplemented with benzylaminopurine at 2.2 µM yielded a vegetative growth increase from 1 to 7 shoots, 2 to 12 leaves per node cutting, and the stem length of 3 to 9.5 cm. The leaf explant induced three ways of in vitro morphogenesis: direct and indirect roots organogenesis (rhizogenesis) and, shoot organogenesis. Direct rhizogenesis was induced in plant growth regulator-free Murashige and Skoog medium (18 roots/explant). Indirect rhizogenesis from leaf explant was less efficient than direct rhizogenesis, get obtaining six roots per leaf explant cultured on Murashige and Skoog medium at 4.4 g L-1 supplemented with 0.4 µM thidiazuron and 4.5 µM 2,4-dichlorophenoxyacetic acid, and three roots per leaf explant cultured on Murashige and Skoog medium supplemented with 0.4 µM thidiazuron and 9.05 µM 2,4-dichlorophenoxyacetic acid. Indirect shoot organogenesis was induced from leaf explants cultured on Murashige and Skoog at 4.4 g L-1 supplemented with 13.32 µM benzylaminopurine and 4.83 µM naphthalene acetic acid; 50% of explants with callus formed shoots (2 shoots/leaf explant). Through histological analysis it was possible to verify that the morphogenic response obtained was organogenesis. Implications: Regeneration of Dendranthema grandiflora var. Micromargara established herein will allow improvement of the variety through techniques of genetic transformation mediated by Agrobacterium and any other strategy to incorporate or silence genes of interest in the plant. Conclusion: The high capacity to induce roots of Dendranthema grandiflora var Micromargara, may provide an efficient model for further investigating the mechanism of rhizogenesis from leaf explants cultured without plant growth regulators.