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

Objective: the objective was evaluating the effect of plant spacing on seed yield andquality in Megathyrsus maximus cv. Mombaza.Design/methodology/approach: the experiment was carried out in rain fedconditions in 2009, at the Universidad del Papaloapan, Campus Loma Bonita,Oaxaca, Mexico. Six plant distances (T1:broadcast, T2:25*25 cm, T3:50*50 cm,T4:75*75 cm, T5:100*100 cm and T6:125*125 cm between rows and plants,respectively) were assessed. Treatments were distributed in a completelyrandomized block design, with four replicates. Total seed yield (TSY), pure seed yield(PSY), percentage of pure seed (PPS), stems plant -1 , stems m -2 , panicles plant -1 ,panicles m -2 , and plants m -2 were evaluated. TSY and PSY showed differences amongtreatments (P<0.01), and the highest values (126.9 and 161.2 kg ha -1 , respectively)were obtained at the 25*25 cm spacing, with a PPS of 74.7%.Results: stems plant -1 , panicles plant -1 , stems m -2 , panicles m -2 , and plants m -2 showeddifferences among treatments (P<0.01). Panicles m -2 was the yield component whichshowed a greater association with PSY with r value of 0.7.Findings/conclusions: as a conclusion, it can be stated that the largest seed yieldof M. maximus cv. Mombaza was obtained at the 25*25 cm spacing between rowsand plants, respectively.

The purpose of this study is to present the results of the cost - benefit analysis of postioplasty in bulls for re-entry into reproductive programs in bovine production companies. A non-probabilistic descriptive study was conducted. The patients were 10 bulls bull, with good body condition and chronic ulcerative balanoposthitis. 2% xylazine was applied at the dose of 0.1 mg / kg body weight as a tranquilizer intramuscularly. An incision was made in the mucocutaneous limbus. Large caliber vessels were ligated with transfixion points. The dissemination is done in 360 ° until the detachment of all the affected tissue including the damaged prepucial mucosa is achieved. 4 points of cardinal form with monophilic nylon suture were placed to expand the mucosa and be able to suture it to the skin, those same fastening points were fixed with a surgeon's point and subsequently 4 points were placed between them. The results of this study allow us to conclude that postioplasty in bulls for re-entry into reproductive programs in bovine production companies can be used for the bull to fulfill its zootechnical function. Regarding the cost benefit ratio of the present investigation, it was 4.2 pesos M / N, which means that for each peso invested, said peso was recovered and an extra gain of $ 3.2 pesos M / N was obtained and the investment is recovered in a 21 day period.

ABSTRACT Objective: To identify the species of insects that feed and damage plants of the genus Heliconia (Heliconiaceae) in commercial plantations in the state of Tabasco, Mexico. Design/methodology/approach: From January to October 2013, three plantations located in the municipalities of Cardenas, Comalcalco and Teapa were visited biweekly to detect phytophagous insects. Results: Four species of insects belonging to three orders and three families were identified: Cephaloleia sallei (Coleoptera: Chrysomelidae) associated with H. psittacorum, Cephaloleia vicina (Coleoptera: Chrysomelidae) associated with H. latisphata, Pentalonia sp. (Hemiptera: Aphididae) associated with H. latisphata, and Telchin atymnius futilis (Lepidoptera: Castniidae) associated with H. psittacorum, H. bihai and H. stricta. Limitations/implications: Pentalonia sp. could not be registered at the species level. For this, a study is suggested that takes into account aphids of this genus also collected in banana plants (Musa spp.) and other hosts. Findings/conclusions: Few species of insects were found feeding or damaging cultivated heliconias; however, these insects are considered to have the potential to affect the crop or the product intended for cut flowers.

Objective: Select the type and dose of fertilizer suitable for the best quality, highest accumulation of dry biomass and photosynthetic rate in plants of G. americana L. during the nursery stage. Design/methodology/approach: A completely randomized experimental design with four repetitions was used. The plants were evaluated for a period of three months in nursery, for which at 20 days of age they were transplanted in 310 cm3 polyethylene tubes using a substrate composed of vermiculite, perlite and peat, which was mixed with Conventional fertilizer (CF) Triple 17 (17N-17P-17K) in doses of 3.3 (low), 6.6 (medium) and 10 kg * m-3 (high), and Osmocote® controlled release fertilizer (CRF) (15N-9P -12K), in doses of 10 (low), 20 (medium) and 30 kg * m-3 (high), plus a control without fertilization. The variables were measured: neck diameter, height, root length, aerial and radical biomass, robustness index (IR), biometric proportionality index (IPB), Dickson quality index (ICD) and photosynthetic rate. The averages were compared by the Tukey test at a 5% confidence level. Results: The plants of G. americana L. fertilized with Osmocote® in its three doses (high, medium and low) showed the highest growth in all morphological variables; in IR the Osmocote® generated plants of better quality than the control, the IPB only the high dose of Osmocote® was different from the control although it is considered of lower quality; and in the ICD the low and medium doses were better than the control since they are considered of better quality; the photosynthetic rate was better with the application of Osmocote® fertilizer in all its doses than Triple 17 and the control. Limitations on study/implications: The low dose (10 kg * m-3) of the Osmocote® fertilizer presents a good option to generate plants of G. americana L. since it did not show differences with the high dose, however nutritional deficiencies will be noticed after three months after of the transplant. Findings/conclusions: With the application of the Osmocote® controlled-release fertilizer in its three doses, plants of G. americana L. are obtained with better morphological attributes, greater biomass accumulation and photosynthetic rate than with the application of the conventional Triple 17 fertilizer.

A qualitative non-experimental-participatory research-action study was carried out from November 2018 to March 2019, with the main objective of identifying the problematic faced by habanero chili producers in Campeche, Mexico, in order to provide a framework for the decision-making, as well as generating a baseline for further studies. A set of indicators was constructed by applying the MESMIS method for the general characterization of the production system. The critical factors were identified on the basis of a participatory rural diagnosis, by selecting the producers who most explained the resolution of the critical points using indicators. A structured survey was applied to diagnose the technological level and the benefits from the activity. As a result, the producers were divided into four levels according to their productive and technological capacity, and the network of total exchanges which characterizes the production system was built. Despite the good results of the activity, its main limitations are as follows: insufficient management of irrigation water, lack of technology transfer, incidence of diseases and pests, excessive use of agrochemicals, lack of capital, inputs expensive, guaranteed prices non-existent, few commercial varieties, lack of added value, lack of organization among producers and poor marketing channels. If these limits are lifted, growing habanero chilis will be a more profitable and competitive activity.

Objective: This work explores obtaining high quality cellulose from pineapple residues. Design/methodology/approach: Pineapple crowns were used to obtain the cellulose using the 0.5% acid pre-hydrolysis treatment with sulfuric acid combined with the Sosa-Anthraquinone pulping method (SQ) and elemental chlorine-free bleaching (ECF). The cellulose obtained was characterized by the TAPPI techniques of Fourier Transformed Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD) and Scanning Electron Microscopy with coupled elemental analyzer (SEM-EDX). Results: It was demonstrated that cellulose-free cellulose was obtained from the chlorination and bleaching stages determined by SEM elemental analysis (EDX) with an alpha (?) cellulose content of 93%, which exhibits the typical crystalline structure of type I cellulose commonly found in the natural plant fibers, Limitations of the study/implications: In the process, a relatively low fiber yield of 29.3% was obtained. Findings/conclusions: Obtaining cellulose from pineapple residues (crowns) is proposed as an alternative of use due to its reinforcement capacity in composite materials, as well as in the production of biomaterials; showing that agricultural residues from pineapple are feasible to obtain cellulose.  

Abstract Objetive: To characterize the agents of the value chain and marketing channels of strand cheese in the municipality of Vega de Alatorre, Veracruz. Methodology: A survey study was conducted, from June-August 2019 through interviews. 61 of these were applied to dairy farmers and 22 dairy processors (cheese factories). Through the Localized Agrifood Systems (SIAL) and value chain approaches. Results: The strand cheese value chain in the municipality is made up of input suppliers, farmers, gatherers, cheese makers, marketers and final consumer. The commercialization of strand cheese has five channels: the cheese maker moves his production where he sells to wholesalers and retailers, sale in stores, establishments or restaurants in the region, sale to intermediaries who come to the plant to buy the product, direct sale, in traditional shop or cremerie in the municipality and small-scale home sales to final consumers. Limitations on study: distrust by some agents to provide information for the study, due basically to the insecurity that exists in the state of Veracruz. conclusion: limitations were found for the development and integration of the value chain. The lack of purchase and sale contracts and of collaborating agreements. Prices are set subjectively; In addition, to influence the market price, producers and / or processors arbitrarily condition the supply or demand of both milk and cheese, which creates market failures and makes it imperfect.

Objective: The in vitro mycelial growth rate of Schizophyllum commune Fr. 1815 strainsfrom Tabasco, Mexico and the production of basidiomas in different regional agriculturalsubstrates was evaluated. Four strains were used: CCG003, CGG009, CCG010 andCGG13, and four substrates: cocoa peel (CP), banana leaves (BL), corn leaves (CL)and as a control, mulatto wood (MW). Based on the speed of growth, two strains andthree substrates were selected to evaluate the basidiomas production in two types ofcontainers: plastic bags and rectangular trays. Productivity was assessed based onBiological Efficiency (BE), Yield (Y) and Production Rate (PR). At 12 days of incubation,the highest mycelial growth rate was recorded in CP by CCG003 and CCG013 strains(51.6±22.1, and 64.4±18.1 mm d -1 ) and in HM and HP by CCG009 and CCG010 strains(86.9±17.8, and 58±7.8 mm d -1 ), compared to the control substrate (from 117.2±7.4 to 2120± 0.0 mm d -1 ). High production was recorded in the CC by the CCG009 strain, grownin bags, with BE of 12.8±2.6%, Y of 4.1 ± 0.8% and PR of 0.7±0.1%. The production ofS. commune was better in the bag than in the tray. This study represents an advance inthe production of basidiomas of this important fungus, as a food alternative for thetropical regions of Mexico.

Objective: To analyze the effect of the addition of charcoal residues on physical and chemical properties of an Acrisol cultivated with sugar cane in the savannah of Huimanguillo, Tabasco, Mexico. Design/methodology/approach: Unmarketable waste charcoal were used, from the company "El Cocoite", from Villahermosa, Tabasco, Mexico. An incubation with charcoal mixed with 300 g of soil was performed for different treatments: 0, 1.2g, 1.8g, 2.4g, 3.0g, 3.6 g, 4.2 g and 4.8 g. Two samples were made at 45 and 90 days, in each sample the soil moisture (SM), bulk density (Bd), pH (H2O), organic carbon (OC), C / N, cation exchange capacity was measured (CEC), exchangeables bases, and exchangeable acidity were evaluating. Results: The soil was improved in physical properties: by increasing soil moisture and keeping an appropriate Bd. The chemical properties such as CO, pH, CIC, Ca 2+, Mg 2+ Na+ and K+, were improved, and the exchangeable acidity reduced. Limitations/study implications: Low crop yield in Acrisols used for sugar cane cultivation, limit the sustainability of this high economic impact agricultural activity in the Southeast of Mexico. Findings/conclusions: This would help improve the availability of plant nutrients in the Ferric Acrisol cultivated with sugar cane.

Objective: Register prehispanic and novohispanic drinks made from cacao and corn and consumed in the Chontalpa Region of Tabasco, México. Design/Methodology: The study was conducted in rural and urban communities of the municipalities of Cunduacan, Cardenas and Huimanguillo. Participatory observation in cocoa and Day of the Dead rituals, workshops and six semi-structured interviews were conducted. It was complemented with a documentary review. The information was analyzed with a matrix of importance to determine the preference of drinks reported and consumed by the population. Results: 29 drinks based on cocoa and / or corn were found, 22 were prehispanics and seven were novohispanics. Of seven corn-based drinks, two are alcoholic and only consumed in rituals. 13 drinks are based on cocoa and corn; 5 drinks include honey, sugar, vanilla and milk, and one drink is made of pure cocoa, reported in the literature as bitter chocolate. Three drinks are based on cocoa husk (cocoa tea) and cocoa cob mucilage (jacket atole). The drinks most preferred by the population of Tabasco are: pozol, cocoa powder, cocoa atole, women's atole, and bitter chocolate. Limitations of the study/Implications: In the sacred rituals for cocoa it is forbidden to record, take photos and videos. The above limited to have evidence of photos and audios. Findings/Conclusions: Of the 29 reported drinks based on cocoa and / or corn, cocoa pozol and cocoa powder are the most preferred. The first is a pre-hispanic drink and combines cocoa and corn.