Search

El objetivo de este trabajo fue analizar el impacto del control estratégico de Rhipicephalus microplus sobre la ganancia de peso de vaquillas Braford en el noreste de Argentina. Se realizaron dos experimentos con un diseño similar en localidades de Corrientes (Colonia Tabay) y Chaco (Colonia Benítez). Los distintos grupos de vaquillas fueron sujetos a esquemas de control estratégico que consistieron en la aplicación de tres o cuatro productos garrapaticidas entre agosto y diciembre, y se compararon el número de garrapatas y la ganancia diaria de peso (GDP) entre estos y un grupo testigo que no recibió garrapaticidas. En Colonia Tabay, en los dos grupos tratados con esquemas de control estratégico la GDP fue significativamente mayor que en el grupo testigo con mayor nivel de infestación con garrapatas. El grupo sujeto a control estratégico en Colonia Benítez también tuvo una GDP significativamente mayor que el grupo testigo. Las diferencias en las GDP entre los grupos de animales sujetos a control estratégico y aquellos mantenidos como grupos testigo fluctuó entre 0.09 y 0.149 kg/día. Para el período evaluado en este trabajo (nueve meses), la aplicación del control estratégico contra R. microplus implicó una ganancia diferencial con respecto a los grupos sin tratamientos de 29 y 42 kg en promedio en las vaquillas de Colonia Tabay y de 25 kg en aquellas de Colonia Benítez. De los resultados se desprende que la aplicación de esquemas de tratamientos estratégicos para controlar la infestación con R. microplus en el noreste de Argentina contribuye a disminuir significativamente la abundancia de garrapatas y posibilita obtener mejores ganancias de peso vivo en bovinos en crecimiento al prevenir altos niveles de parasitación en los animales.

Se analizaron las especies de garrapatas del género Amblyomma en relación a las áreas fitogeográficas argentinas donde fueron colectados los especímenes y al rango de hospedadores. Se determinó un total de 22 especies con una mayoría en el dominio del Chaco (17 especies, 8 exclusivas), seguido por el dominio Amazónico (13 especies, 5 exclusivas) y el Andino-Patagónico (3 especies). Diez especies fueron asociadas al hombre, 13 sobre animales domésticos y otras sobre una gran variedad de animales silvestres. Considerando este amplio rango de hospedadores, sería conveniente estudiar su ecología y potencial para transmitir enfermedades.

Se evaluó la susceptibilidad-resistencia de poblaciones argentinas de la garrapata Rhipicephalus microplus (83 poblaciones) y de la mosca Haematobia irritans (125 poblaciones) a la cipermetrina (piretroide) y al diazinón (órgano-fosforado), respectivamente. No se detectaron poblaciones de H. irritans resistentes al diazinón pero se determinaron 19 poblaciones de garrapatas resistentes a la cipermetrina. La mayoría (15) de ellas se concentró en el litoral, especialmente en Corrientes, donde predominan condiciones de mayor aptitud para el desarrollo de R. microplus; la frecuencia anual de tratamiento con acaricidas es alta y los piretroides fueron reemplazados en buena medida por acaricidas a base de formamidina y avermectinas. El resto de las poblaciones resistentes fueron determinadas en el área oeste de la distribución de la garrapata (tres en Córdoba, una en Salta) donde la apatitud para el desarrollo de R. microplus es intermedia y la frecuencia anual de tratamientos es menor que en el este. Se destaca la conveniencia de mantener la evaluación continua del status de la susceptibilidad-resistencia de la H. irritans a los órgano-fosforados para alertar en forma temprana si se comprobara algún cambio en la situación actual. Se considera necesario continuar con la evaluación de la susceptibilidad-resistencia de R. microplus a los piretroides en las áreas donde las poblaciones son aún susceptibles e incorporar técnicas para el diagnóstico de resistencia a formamidinas y avermectinas que son utilizados como acaricidas en una proporción importante de establecimientos ganaderos.

Se analizaron las especies de garrapatas de las familias Argasidae e Ixodidae, con excepción del género Amblyomma, en relación con la fitogeografía de la Argentina. Se determinaron 3 especies de Argas, 3 de Ornithodoros y 1 de Otobius para Argasidae, pero se presume que Argas miniatus está también establecido. Un total de 14 especies de Ixodidae están representadas en el país para el conjunto de los géneros Dermacentor (1 especie), Haemaphysalis (2 especies), Ixodes (9 especies) y Rhipicephalus (2 especies). La mayoría de taxones (15) se determinó para el dominio del Chaco, 4 exclusivos de este dominio, seguido por el dominio Amazónico (10 especies, 2 exclusivas) y el Andino- Patagónico, con 8 taxones (3 exclusivos). Nueve especies fueron determinadas sobre el hombre y 9 sobre animales domésticos, indicando la conveniencia de impulsar estudios sobre su ecología y potencial para transmitir enfermedades.

Drought is a major abiotic stress affecting plant growth and productivity worldwide. Henna (Lawsonia inermis L.) is an economically important plant species that is widely cultivated due to its natural dye properties and medicinal uses, and it is highly susceptible to drought stress, which limits its growth and development. This study was conducted with the aim of investigating the effect of foliar spraying of sodium nitroprusside (SNP) on the yield of henna ecotypes (Lawsonia inermis L.) under drought stress conditions in Shahdad-Iran. The experiment was conducted in the form of a split factorial design based on randomized complete block design (RCBD) in three replications. Three ecotypes of henna (Rudbar-e-Jonub, Shahdad, and Bam) were used as plant material. The findings showed that with the onset of drought, photosynthetic pigments, growth indices, net photosynthesis, and yield of dry matter of henna plant leaves decrease. However, when SNP spray treatment was applied, it significantly improved things like leaf area index, crop growth rate, net photosynthesis and leaf dry matter yield, especially when drought levels were at 25 and 50%. The natural water content of Shahdad genotype in henna plants showed the highest percentage increase in these measurements compared with other henna plant species. It can be concluded that SNP spray can increase the yield of henna plant under drought stress conditions.

Background: Camote de cerro (Dioscorea remotiflora Kunth) stands out as a crop option in protected agriculture in Mexico due to its agronomic benefits and its versatility in the food and pharmaceutical industries. Despite its potential, it is not commercially cultivated in the country motivating the need to develop an efficient propagation method from vegetative planting material. Previous research suggests that the use of growth retardants stimulates root growth and carbohydrates accumulation in tubers, while applying gibberellic acid (GA3) is strongly related with greater tuber production. Objective: To evaluate the effect of different growth regulators to obtain D. remotiflora mini tubers. Methodology: Two experiments to obtain mini tubers were carried out. The first one evaluated mediums of culture in vitro: MS and MS + 0.5 mg L-1 paclobutrazol (PBZ). In the second, effects of foliar application of GA3, PBZ and trinexapac ethyl (TNE) were evaluated. Both experiments were carried out in two accesions of D. remotiflora plants propagated in vitro and adapted to greenhouse conditions. Results: An increase in mini tubers yield and in their weight was observed when seedlings were propagated in MS + 0.5 mg L-1 PBZ and GA3 was applied to foliage. Implications: The use of growth retardants showed efficiency in developing mini tubers; nevertheless, more research focusing on concentrations and combinations of these substances is needed to improve the protocol to obtain planting material. Conclusions: The observed effect of growth retardants and gibberellic acid application in Dioscorea remotiflora plants suggests a favorable influence in the development of mini tubers. In the long term, this phenomenon could contribute significantly to promoting viability of its commercial cultivation and rehabilitation of previously exploited areas.

Los humedales artificiales son eficaces en la eliminación de diversos contaminantes de las aguas residuales. En este trabajo de revisión, se buscó analizar las últimas perspectivas sobre los humedales artificiales de flujo subsuperficial, los que utilizan diferentes metodologías para el tratamiento de efluentes contaminados. Para alcanzar este objetivo, se realizó una búsqueda de información empleando filtros basados en palabras clave, durante el período comprendido del año 2015 al 2021. Se examinaron alrededor de 60 estudios relacionados con los humedales artificiales de flujo subsuperficial horizontal, destacando en los resultados obtenidos los mecanismos de eliminación de contaminantes. Se han obtenido mejoras significativas en sistemas a escala de laboratorio o piloto, pero se debe profundizar en el proceso de escalamiento de estas tecnologías en diferentes configuraciones, para una eficiente eliminación y reducción optima de diferentes contaminantes.

Although the EU is a major producer of honey, commercial production is often insufficient to meet market demand and, as a result, honey is often imported into the EU from extra-EU countries that lack regulatory standards for food safety and quality. Since honey is a matrix highly susceptible to contamination, monitoring the quality and safety of extra-EU honey is of significant importance to show potential safety gaps. Hence, aim of the study was to monitor the mineral profile of monofloral and multifloral honeys from different regions of North (provinces of Tiaret and Laghouat) and South Algeria (province of Tindouf). In almost all the samples, Mg, Fe, Zn, Cd and Pb were found at levels exceeding the limits set for honey by the Codex Alimentarius and European Regulation 915/2023. In addition, a PCA analysis pointed out that the analysis of the element profile was useful to discriminate Algerian honeys more on the basis of geographical than botanical origin. The dietary exposure assessment indicates that the investigated honeys can be safely consumed in quantities comparable to those considered in Europe (1.8 g/day) and North Africa (0.3 g/day). Hopefully, data from this study may solicit the Algerian government to set regulatory limits on inorganic elements in honey and align with other international standards, to create a harmonized network able to improve the safety of this food.

The Green Revolution led to an increased use of synthetic pesticides, causing environmental pollution. As an alternative, biopesticides made from entomopathogenic agents such as fungi have been sought. This study aimed to design and evaluate the performance of a harvester machine for efficiently collecting entomopathogenic spores of Metarhizium anisopliae and Beauveria bassiana grown on rice and corn substrates. The spore yield was estimated, and a spore count and a colony-forming unit (CFU) count were performed. Statistical analysis was conducted to compare the mean values of spores obtained from different combinations of solid substrate and fungi. The Corn-Metarhizium combination produced 34.15 g of spores per kg of substrate and 1.51 × 109 CFUs mL−1. Similarly, the Rice-Metarhizium combination produced 57.35 g per kg and 1.59 × 109 CFUs mL−1. Meanwhile, the Corn-Beauveria combination yielded 35.47 g per kg and 1.00 × 109 CFUs mL−1, while the Rice-Beauveria combination had a yield of 38.26 g per kg and 4.50 × 108 CFUs mL−1. Based on the reported results, the Rice-Metarhizium combination appears to be the most effective, yielding the highest number of harvested spores per kg of substrate. The study estimated a total cost of approximately $409.31 for manufacturing the harvester, considering only the cost of the materials. These results could potentially increase the availability and affordability of entomopathogenic fungi in integrated pest management.

The fungus Ustilago maydis produces galls or tumors on corn ears called corn smut or huitlacoche. Used for human consumption in several countries for its nutritional and sensory traits, huitlacoche is considered a delicacy in Mexican cuisine and has a significant economic value. Hybrid U. maydis strains are regularly used for the large-scale production of huitlacoche; however, depending on the genetic characteristics of the parent strains, the pathogenicity and infection rate of hybrid fungi are often suboptimal due to compatibility issues between different strains. Using double-loaded organisms is common in agriculture to improve product characteristics, performance, and shelf-life. A methodology to obtain unicellular U. maydis strains with a double genetic load (n + n) capable of producing galls on corn ears without mating (hybridization) is reported herein. This methodology resulted in 206 U. maydis isolates. Screening showed that 147 corn plants (>70%) underwent infection and gall production. Of the 147 gall-producing U. maydis strains, those with the highest field performance were selected. Three strains, Um-UAEMor-78 (yielding 21.65 ton/ha), Um-UAEMor-120 (22.31 ton/ha), and Um-UAEMor-187 (22.99 ton/ha), showed higher yields than the control strain, CP-436(a1b1) × CP-437(a2b2) (17.80 ton/ha). A specific methodology to obtain unicellular U. maydis strains with a double genetic load capable of infecting baby corn ears and forming galls is described for the first time, providing a novel alternative for producing huitlacoche and helping to improve the yields and morphological traits of galls.

Background. The vegetative material for in vitro establishment of avocado explants is from the field, for this reason, the proportion of contamination, oxidation and mortality of explants is elevated, therefore we are looking for alternatives to decreased. Objective. To evaluate concentrations of alternative products for disinfestation in avocado explants cv Duke 7, and decrease oxidation with the addition of L-cysteine in the in vitro establishment. Methodology. The products used were: peroxyacetic acid (AP), chlorine dioxide (DC), and quaternary ammonium salts (ACS), in three concentrations. 54 explants were used in each treatment, and placed in culture medium for establishment, evaluating contamination (%) and oxidation (%). Two weeks later, 50% of viable explants from each treatment were immersed in L-cysteine (100 mgL-1) and placed in a culture medium for multiplication, the rest was placed a in multiplication medium containing L-cysteine; only oxidation was evaluated (%). Contaminated explants were isolated, identified, and characterized fungi and bacteria. Results. The best results of the disinfestation were with ACS with 3.7% contamination, without oxidation. Regarding the use of L-cysteine (100 mgL-1), the lowest percentage of oxidation (47%) was obtained when immersed in a cysteine solution. Three genera of fungi were identified: Aspergillus (3), Penicillium (1) and Cladosporium (1), and Agrobacterium as a bacterium. Implications. With the proposed methodology, we can continue with the following stages of in vitro culture, to establish methodologies for budding, growth, and rooting of avocado clonal rootstocks. Conclusions. The use of ACS and cysteine in solution reduces both contamination and oxidation of explants, but it is necessary to modify concentrations and exposure times in the disinfestation protocol, in addition to identifying even the genus the microorganisms found.

ABSTRACT Kidneywood (E. polystachya) is a medicinal plant used for urinary and digestive system infections and inflammations in humans and animals. In addition, kidneywood is used as fodder and its wood is employed in rural housing construction. Populations of this plant have been reduced by the extraction that occurs in its natural habitat; in addition, the germination of its seeds is slow. To improve its germination, this research aimed to evaluate the effect of pre-germination treatments on seed germination and seedling growth of E. polystachya. Seven pre-germination treatments and a control were evaluated in a completely randomized experimental design with four replicates per treatment and 25 seeds per replicate. The results indicated that all treatments applied to the seeds produced higher germination percentages (100 to 182%) and greater seedling growth (14,6 to 59,8% more in height) than the control, with the exception of soaking in water. The pretreatment that generated the best response was the application of AG3 at 600 ppm for 30 min, with 96% germination, 19,4 cm height, 3,9 mm stem diameter, 20 cm root length, 21 leaves per plant and 375 mg dry matter per seedling. Mechanical scarification generated 86% germination, 16,1 cm height, 2,9 mm stem diameter, 18 cm long roots, 12,5 leaves, and 354 mg dry matter, added to which it initiated emergence in less time (3,7 d), also making it a good and less costly option.

Background. Soil management practices modify the microbial communities and the carbon stocks (organic, inorganic, and total). The increase in microbiological communities’ diversity improves the production of plants; thus, it is essential to understand the predominant bacterial taxa in the soil. Objective. The objective of the present study was to establish the bacterial communities’ alteration by agroecological management in maize crops in arid northern Mexico. Methodology. Bacterial diversity and composition were determined in soils from Coahuila, Mexico, under three different scenarios: i) Agroecological management (AM), ii) Conventional management (CM), and iii) Control (T, with no vegetation). In addition, pH, electrical conductivity (EC), and soil organic matter (SOM) were analyzed using standard methods. Bacterial DNA was extracted from the soil, amplifying the V3-V4 region of the 16S rRNA gene and sequencing with Illumina. The gene sequences were analyzed in QIIME. Results. A total of 20 bacterial phyla and 631 genera were registered. For AM, CM, and T, respectively, the most abundant genera were Tepidisphaera (7.02, 9.29, and 9.93 %), Sphingomonas (6.55, 5.15, and 4.06 %), Microvirga (2.64, 2.39, and 3.63 %), and Blastococcus (2.91, 3.10, and 3.37 %). A significant difference was observed among groups (p = 0.004), where AM was different, which suggests that the type of substrate determines the diversity and abundance of the bacterial community. Significant differences were found for pH and EC, with higher pH in CM (7.87) and T (7.86) soils. The EC was higher in AM (446 μ Scm-1) and T (419 μ Scm-1). On the other hand, AM showed the best result in SOM content (21.80 ± 1.10 gC kg-1). Implication. Therefore, AM in maize crops has the potential to conserve or restore C stock in degraded arid lands, increasing bacterial diversity, favoring the health of the soil. Conclusion. Agroecological management of maize crops soils in arid North of Mexico promotes greater bacterial diversity, which will favor the availability of nutrients for the future development of healthy plants.

Forms of aluminum (Al) present in the solution of tropical and subtropical soils can cause toxicity in rootstocks and peach cultivars, impairing growth and productivity. This can be minimized by growing Al-tolerant rootstocks and cultivars. However, this is not sufficiently known, especially because plant breeding programs do not always consider tolerance as a selection variable for genetic materials. The study aimed to (a) select cultivars and clonal selections of Al-tolerant peach rootstocks, (b) identify variables that confer Al tolerance for use in genetic improvement programs, and (c) propose critical levels (NC) and ranges of toxicity (TF) of Al in relation to morphological variables of the root system. The experimental design was completely randomized, comprising a factorial of 13 (cultivars and clonal selections) x 2 (with and without Al) with three replications. Own-rooted ‘BRS Mandinho’ peach seedlings (without rootstock) and grafted seedlings of ‘BRS Mandinho’ on different cultivars and clonal rootstock selections were cultivated in a hydroponic system, composing two levels for the Al factor (absence and presence at 100 mg L−1). The morphological variables of the canopy and root system, Al accumulation in tissues, translocation factor, and the critical level (NC) and toxicity range (TF) of Al in the roots were evaluated. Rootstocks FB-SM-09-43, JB-ESM-09-13, SAS-SAU-09-71, SS-CHI-09-40, ‘Sharpe’ and VEH-GRA-09-55 were tolerant at high Al concentrations. The NC of Al in the roots in relation to the root surface area of peach rootstocks was 1400 mg Al kg−1, and the FT was between 1200 and 1500 mg Al kg−1.

Background: Veracruz is the second largest coffee producer in Mexico and its production is of productive, economic and social importance. Objective: to analyze the participation of women in the coffee production process and decision-making in 11 municipalities in the region of the High Mountains of Veracruz. Methodology: A survey applied through personal interviews was used, with the application of 98 questionnaires to women coffee producers. We worked with two focus groups: coffee plantation owners defined as Women Coffee Producers (MDP, 15) and non-owners of coffee plantations but who participate in family production considered as Family Women Coffee Producers (MFP, 18); A database was created in Excel Microsoft Windows, the data was analyzed with Statistica version 8.0. Results: It was found that the MDPs play a double role (producers and housewives/entrepreneurs/artisans), while the MFPs are exclusively dedicated to the home. Therefore, coupled with the fact that they have land ownership rights, their participation is low. Implications: it is important to carry out research with a gender perspective to recognize the preponderant activity of women, considering men. Conclusions: it is important to encourage women to recognize their work in order to make visible the work carried out on the plots.

Background. “Camote de cerro” (Dioscorea spp.) is a plant of great importance in West rural areas of Mexico as food source and alternative medicine. Dioscorea is an important crop around the world for its carbohydrate contribution to diets. Yams are polyploid plants, and species with modifications at ploidy level also present changes in leaf size and stomata characteristics. These variations can favor resistance to adverse conditions. Objective. In the present study, evaluation and correlation of ploidy levels, leaf size, stomata characteristics and tuber weight were carried out for Dioscorea remotiflora Kunth and Dioscorea sparsiflora Hemsley in accessions obtained from 11 localities in México. Methodology. Chromosome counting was carried out in root meristems. Measuring and counting stomata were carried out. Productivity rate (PR) was calculated dividing harvested tuber weight over seed tuber weight, for each experimental unit. Leaves width and length were measured. Results. Show that variation is higher among different localities than among specimens from the same locality. Significant differences were observed for, ploidy levels (P), stomata dimensions and number of chloroplasts in stomata. Differences in chloroplast numbers present in occlusive cells were also significant for different species. Implications. Ploidy level showed a relation with chloroplasts numbers in stomata and stomata width. Leaf size presented a relation with stomata dimensions, and leaf width showed a relation with tuber weight. Conclusions. These observations allowed us to determine that there are variation among populations; stomata width and chloroplast number in a population can help to determine ploidy levels, and leaf width is a response variable that allows to predict tuber weight.

México es considerado centro de origen del chile (Capsicum annuum L.) y tiene dos grupos de chiles: los comunes (disponibles en todo el país) y los locales. La presente investigación se realizó con el propósito de conocer el comportamiento de los genotipos de chile Huacle negro, rojo y amarillo (chiles locales de Cuicatlán, Oaxaca, utiliza dos para elaborar el mole negro), así como evaluar su rendimiento y calidad bajo condiciones de invernadero con dos sistemas de producción: orgánico e inorgánico, con aplicación y no aplicación de rizo-bacterias Azospirillum sp. La siembra se realizó en charolas de 200 cavidades, utilizando peat moss como sustrato. Los sustratos utilizados fueron: arena + compost con la dosis de a) 20% y b) 35% y para el testigo c) arena al 100%. Las macetas se colocaron a doble hilera en tresbolillo espaciadas a 30 cm entre planta y planta y 80 cm entre pasillos. El diseño experimental utilizado fue en bloques completamente al azar con dos repeticiones y una unidad experimental de ocho macetas por genotipo. Las siguientes variables: altura de planta, número de hojas por planta, peso verde y seco de la parte aérea de la planta, peso verde y seco de la raíz, y número de frutos por planta mostraron valores más altos en el sistema de producción convencional a base de sustrato con arena al 100% y solución nutritiva inorgánica. El rendimiento en seco y la calidad del fruto (diámetro polar, ancho de la cavidad y grosor de pulpa) fueron mayores en el sistema de producción orgánico a base de compost y aplicaciones de Azospirillum. Se puede concluir que los genotipos de chile Huacle, el genotipo negro, se adaptaron de manera favorable al sistema de producción orgánico con dosis de 20% de compost y aplicaciones de Azospirillum.

The objective of this study was to compare pregnancy rates in domestic cats using fresh semen for the bilateral intrauterine insemination (BIUI) method and the novel uterine body insemination (UBI) method. Queens received a single injection of equine chorionic gonadotropin (eCG) (200 IU; IM) to induce ovarian follicular development and, after 83 h, an injection of human chorionic gonadotropin (hCG) (100 IU; IM) for final oocyte maturation and ovulation induction. Thirty-four hours after hCG administration, 3 × 106 fresh spermatozoa were used for insemination by the BIUI (n = 8 queens) or by the UBI (n = 7 queens) techniques respectively. Pregnancy rates were 75.00% (6/8) by BIUI and 42.85% (3/7) by the UBI method. The mean litter size was 3.0 ± 0.86 for the BIUI, and 2.0 ± 1.0 for the UBI method. Spontaneous abortion occurred on day 35 of pregnancy in one queen following the UBI method. Our findings showed that the BIUI of queens with fresh semen resulted in higher pregnancy rates than the novel UBI method; also, acceptable pregnancy rates were achieved following BIUI with fresh semen in the domestic cat.

Background. The fishing problem in the Lagunar de Alvarado System (LAS), taking into account environmental or socioeconomic aspects, has been analyzed by various authors, but few have addressed the relationship between environmental problems as perceived by fishermen, and migration. Objective. To identify the migration phenomenon in three zones of the LAS and its relationship with environmental problems perceived by fishermen. Methodology. Information was compiled from a survey applied to 32 Family Fishing Units. To quantify the environmental problem perceived and relate it to migration, three indicators were used: Pollution Perceived by fishermen, State of Perceived Health of the Fishery Resource and State of Perceived Health of the Environment. Results. The wetland areas have more precarious socioeconomic conditions than the area that borders the mainland, while migration and perceived environmental problems vary in each zone. Implications. Because the causes of migration are multiple, environmental deterioration has an impact on this phenomenon but does not explain it by itself. Therefore, more comprehensive analyses are required. Conclusions. There is insufficient evidence to affirm that the environmental deterioration identified by fishermen is an important motivation for migration.

Mathematical models that simulate crop development are important tools to help growers plan management practices and harvest time for cut flowers such as gladiolus. The objective of this work was to validate the PhenoGlad model for the State of Paraná, determining the planting date for marketing flowers for the Day of the Dead, and the quality of the floral stems. The validation of the PhenoGlad model was carried out through field tests in five towns in the State of Paraná, namely: Cascavel, Dois Vizinhos, Marechal Cândido Rondon, Palotina, and Santa Helena. The experiments were carried out during the year 2019. The PhenoGlad model was run for each location and year of meteorological data for the early, The PhenoGlad model was simulated for each location and period of meteorological data available at each weather station in these towns, and for the early, intermediate II, and late development cycles. The planting date was determined through the average of the dates (Julian days) for each simulated year. The variables analyzed were the stages of development according to the phenological scale of the culture, the number of leaves, the average number of florets, and the classification of floral stems according to the quality standards of Veilling Holambra. The PhenoGlad model showed accuracy in simulating the stages of development of gladiolus culture in the state of Paraná and is also suitable for predicting the damage caused by extreme temperatures in floral stems, which was confirmed by the damage caused to sepals and petals of gladiolus in field experiments in the towns of Cascavel, Dois Vizinhos, Palotina, and Santa Helena. The best model performance was observed when simulating the vegetative period of the crop, presenting a low error of 0.54 leaf. In the state of Paraná, for the production of floral stems for the Day of the Dead, the PhenoGlad model simulated the planting dates in the different towns studied from August 1 to August 23. The towns of Cascavel and Marechal Cândido Rondon presented a higher number of florets and higher quality of floral stems than the other towns evaluated.

La papaya (Carica papaya L.) es un cultivo de importancia económica en México y América Latina. La fase de vivero juega un papel primordial en el proceso de producción, en esta etapa es susceptible a plagas y enfermedades. El uso de biofertilizantes a base de hongos entomopatógenos (HE) es una alternativa para producir plántulas sanas y de calidad, a través de la agricultura biológica. El objetivo fue evaluar la habilidad de Beauveria brongniartii y Purpureocilium lilacinum para colonizar tejidos, promover la emergencia y mejorar la calidad de planta de dos genotipos de papaya en vivero. Se estableció un experimento con diseño factorial A×B [A = genotipo: híbrido “Intenzza” y var. “Maradol”) y B = inoculación de B. brongniartii (Bb), P. lilacinum (Pl) y sin inoculación]. Se cuantificó, el porcentaje de emergencia (PE), Altura de Planta (AP), Diámetro de Tallo (DT), Biomasa Fresca (BF) y Seca (BS), endofitismo, Índice de Lignificación (ILIG) y Calidad de Dickson (ICD). El PE incrementó (6%, P = 0,0043) con la inoculación de Bb. Ambos HE incrementaron la AP (P = 0,00001) en 0,38 (Bb) y 0,37 cm (Pl), y el DT (P = 0,00001) en 0,24 (Bb) y 0,23 mm (Pl), respectivamente. La BF aérea y radicular (P = 0,0003) incrementó con Bb y Pl en 0,16 y 0,1 g y 0,17 y 0,1 g, respectivamente. El ILIG (P = 0,0128) e ICD (P = 0,0433) fueron superiores con Bb. Tanto Bb y Pl colonizaron diferentes tejidos de la planta. La inoculación de Bb promovió la emergencia de semillas. Ambos HE lograron colonizar endofíticamente diferentes órganos de la planta y favorecieron su calidad.

Arsenic (As) is a metalloid present in the hydrosphere, lithosphere, and biosphere that at high concentrations causes toxicity in organisms through complex mechanisms. Moreover, the main As sources in ecosystems are both natural and anthropogenic, so it is difficult to avoid this contamination. Certain regions in the world have that characteristics and present high arsenic accumulation in soil, water, and sediments, producing toxicity in crops, livestock, and consequently, in human consumers. In Latin America, this phenomenon occurs in countries such as Chile, Argentina, and Mexico. This review describes the generalities of origin and distribution of arsenic, focusing on toxicity problems in crops that affect in the Comarca Lagunera in northern Mexico, which represents one of the main As-contaminated regions worldwide. Although some studies have been carried out to analyze and solve this problem, the available information remains scarce, especially about the prevalence of As in the food chain and how to address As contamination. Thus, this review includes biological alternatives of solutions such as bioremediation techniques using mycorrhizas and rhizobacteria such as plant growth-promoting bacteria (PGPB) in soils to mitigate the toxicity caused in crops and soils.

The reclaim of less-used plant sources is a novel approach to the growing demand for healthy and eco-friendly foods, and it constitutes a sustainable alternative to replace conventional food ingredients and sources of bioactives. In this work, a phytochemical profile in terms of mineral elements, total polyphenols, fatty acids, α-tocopherol, sterols, and squalene was realized for several commercial edible oils of bitter almond, pumpkin seed, apricot kernel, nigella, souchet, and wheat germ sourced in the Tunisian market. Wheat germ oil, which showed the most significant nutritional and healthy impact, contained the highest contents of Mg (52.37 mg kg−1); Na (40.75 mg kg−1); Mn (2.39 mg kg−1); total sterols (1713.80 mg/100 g); and PUFAs (61.01%). The high levels of squalene detected on pumpkin seed oils (1160.01 mg kg−1) allows to proposet it as valuable functional food. The highest total polyphenolic content found in nigella oils (109.01 mg GAE kg−1) justifies its stability and antioxidant properties. A daily consumption of 10 g of bitter almond or souchet oil contributes to a 17.53% and 8.6% alpha-tocopherol daily intake, respectively. The usual consumption of these minor oils may represent a sustainable and convenient source of bioactives with beneficial effects on both human health and nutrition.

O objetivo deste trabalho foi avaliar a concentração de nutrientes nas folhas e o rendimento de maçãs em função do uso da irrigação e da forma de aplicação de adubos ao solo (convencional sólida ou fertirrigação). O experimento foi conduzido na safra 2014/15 em um pomar instalado sobre um Cambissolo Húmico, em São Joaquim (SC), com o cultivar Kinkas. Os tratamentos foram: adubação sólida convencional (ASC); adubação sólida convencional + irrigação (ASC+I); fertirrigação (F); e fertirrigação + irrigação (F+I). Utilizou-se o delineamento experimental de blocos ao acaso, com oito repetições. A necessidade e o tempo de irrigação foram determinados pela média das leituras dos tensiômetros instalados entre as unidades experimentais. Foram avaliados os teores de Ca, Mg, P e K no solo e nas folhas, os parâmetros de produtividade, sólidos solúveis, acidez titulável e firmeza de polpa. O número e a produtividade de frutos, assim como os atributos de solo, não foram afetados pelos tratamentos. Nas folhas, os teores de Ca foram maiores no tratamento com I+F em relação ao com ASC+I; para Mg, os maiores teores ocorreram nos tratamentos com ASC e ASC+I; para o K, os tratamentos com I+F e F foram os que apresentaram os maiores teores. A menor concentração de açúcares nos frutos ocorreu no tratamento com fertirrigação. Apesar de afetar a composição das folhas, a forma de aplicação dos adubos e a irrigação não afetaram a produtividade de maçãs.

Anthracnose disease is a major disease in cayenne pepper triggered by fungal pathogen Colletotrichum capsici which can cause yield losses of up to 90%. Control of disease generally utilizes synthetic fungicides, but it damages the environment and human health. Hence, alternative controls that are ecofriendly are required. One of the attempts is to make use of chitinolytic bacteria's potential. This study aimed to screen UB Forest chitinolytic bacteria and to determine their potential in suppressing anthracnose in cayenne pepper. Stages of research include a screening of 78 UB Forest bacteria as chitinolytic bacteria, selection of chitinolytic bacteria that are antagonistic against C. capsici, inhibition test of chitinase crude extracts against C. capsici growth, controlling anthracnose disease in cayenne using chitinolytic bacteria, and molecular identification. Based on the results of the selection, there were 76 isolates of UB Forest bacteria classified as chitinolytic bacteria, 74 bacteria antagonistic against C. capsici. Chitinase crude extracts significantly affected C. capsici growth inhibition compared to fungicide treatment. The application of Pseudomonas aeruginosa (UB 11) and Bacillus cereus (UB 12) can control anthracnose disease in cayenne pepper with the intensity of 41.67% and 38.89% respectively with the efficacy level of 58.33% and 61.11%.

Compreender as fases e a dinâmica da dormência de cultivares comerciais na região em que essa está inserida possibilita a execução de diferentes práticas culturais e auxilia na compreensão dos requisitos de frio e calor exigidos pela mesma, colaborando principalmente com os programas de melhoramento genético. O objetivo deste trabalho foi determinar as taxas de brotação, floração e frutificação efetiva de pessegueiros sob as condições ambientais de cultivo no município de Dois Vizinhos, região Sudoeste do Paraná. O presente trabalho foi desenvolvido na coleção de pessegueiros do setor de Fruticultura da Universidade Tecnológica Federal do Paraná. Foram avaliadas 16 cultivares de pessegueiros, sendo ‘Rubimel’, ‘Leonense’, ‘Coral, ‘Marli’, ‘Charme’, ‘Riograndense’, ‘Douradão’, ‘Chimarrita’, ‘Granada’, ‘BR-1’, ‘Bonão’ e ‘Eldorado’ implantadas em 2009 e ‘Regalo’, ‘Kampai’, ‘Fascínio’ e ‘Zilli’, implantadas em 2014. O delineamento experimental foi inteiramente casualizado com quatro repetições de uma planta cada, no arranjo bifatorial 16 x 2 (cultivares x anos/safra). As avaliações de fenologia foram realizadas semanalmente através da contagem de gemas florais abertas (antese) e brotadas, e a taxa de frutificação efetiva foi realizada imediatamente antes do raleio de frutos. Foram calculadas as taxas de floração (%), de brotação (%) e de frutificação efetiva (%). Nas condições climáticas do município de Dois Vizinhos, no Estado do Paraná, verificou-se que o ano/safra 2016 promoveu as maiores taxas de brotação e frutificação efetiva. A cultivar ‘Bonão’ apresentou maior intensidade e regularidade de floração nos anos safra avaliados (2016 e 2017). As cultivares ‘Coral’ e ‘Kampai’ apresentam frutificação efetiva com maior intensidades e regularidade em relação aos demais cultivares avaliados para a condição de clima do local avaliado. A cultivar ‘Riograndense’ apresentou maior irregularidade na floração e na produção de frutos.

Background. Resistance to an insecticide is what determines its effectiveness and the lack of information limits effectiveness in the control of the boll weevil in cotton crops. Objective. The objective of the study was to determine the susceptibility of the boll weevil (Anthonomus grandis Boheman) to malathion in the Laguna, Mexico. Currently, this pest is considered as the one with the highest economical impact on cotton cultivation in the region. Methodology. Three bioassays were carried out, one in the state of Coahuila in the 2017 agricultural season and in the 2018 and 2019 seasons in the states of Coahuila and Durango. Boll weevils reared in the laboratory, as well as those collected in the field were used to obtain DL50 and DL95. The mortality data was analyzed using the Probit analysis. Results. The mean lethal dose after 48 hours in the three agricultural cycles fluctuated between 0.19 and 0.39 µg/µl for adults raised in the laboratory and the data observed for adults collected in the field was between 0.37 and 0.44 µg/µl. Implications. Periodic bioassays are suggested to detect populations resistant to malathion. Conclusion. It was determined that the boll weevil populations in the Laguna Region were susceptible to malathion, since the mean lethal dosage for the 3 agricultural seasons was < 1 µg/µl.

Introducción. La marchitez por Fusarium de los bananos y plátanos (Musa spp.) es causada por el hongo Fusarium oxysporum f.sp. cubense (Foc) (Ploetz, 2015), la cual es considerada como la enfermedad de mayor importancia a nivel mundial por los daños destructivos en el cultivo (Dita et al., 2018). Objetivo. Conocer el impacto en la industria bananera y la distribución de Fusarium raza tropical 4. Métodos. La presencia de Foc en Colombia (2019) y Perú (2021), países exportadores de América Latina y el Caribe (ALC), alertó para iniciar la exclusión y esta fue establecida en varios países del continente americano. Resultados y discusión. La naturaleza de Foc y su persistencia en el suelo es irreversible e intratable durante décadas (Dita et al., 2018), por lo que las áreas infectadas llegan a ser no aptas para cultivar banano (Ploetz, 2015). Foc es un patógeno con una alta variabilidad genética, el cual está compuesto por diferentes linajes; actualmente se reportan 24 grupos de compatibilidad vegetati- va (GCVs) distribuidos a escala mundial (Ordoñez et al., 2015). Conclusión. La presencia de Fusarium raza tropical 4 en ALC, alerta al resto de los países a aplicar medidas de bioseguridad para prevenir su ingreso.

O conhecimento da fenologia permite identificar o momento fisiológico ao qual se encontram associadas as necessidades do vegetal que, uma vez atendidas, possibilitarão definir períodos propícios para a realização dos tratos culturais e de manejo. Nesse contexto, o objetivo desse trabalho foi descrever a escala BBCH para nogueira-pecã, de forma a padronizar os estudos realizados sobre o tema e auxiliar no reconhecimento dos principais estádios fenológicos da espécie no Rio Grande do Sul – Brasil e Uruguai. Para a descrição da escala fenológica utilizou-se diferentes cultivares para representar a média de cada estádio fenológico da cultura em dois locais e em dois ciclos. Com base na escala BBCH original, foi descrito a escala fenológica para nogueira-pecã totalizando 34 estádios que permitem identificar as principais fases do desenvolvimento, através de uma abordagem precisa e simplificada. Essa escala permite, através da codificação utilizada, padronizar e uniformizar os estudos sobre a cultura.

Background. The genus Metarhizium is integrated of various species, they have a wide geographic distribution and are considered one of the best biological control agents for pests insect. Objective. To determine the genetic diversity of Metarhizium strains isolated from different insects and agroecosystems using RAPD markers. Methodology. Soil was collected from different agroecosystems (Mexican lemon, grapefruit, sugar cane, mango), insects Diatraea saccharalis (Lepidoptera: Crambidae), Diatraea magnifactella (Lepidoptera: Crambidae), Schistocerca piceifrons piceifrons (Orthoptera: Acridylus), Macrodactylus murinus (Coleoptera: Scarabaeidae), Spodoptera frugiperda (Lepidoptera: Noctuidae) and the mite Boophilus microplus (Acari: Ixodidae) to isolate Metarhizium strains, the isolates were analyzed through random amplified polymorphic DNA (RAPD) markers. Results. The RAPD markers were highly informative and polymorphic. The generated dendrogram was made up of four clusters (A-D); cluster A consisted of 11 soil isolates, one from D. magnifactella and two from D. saccharalis. In cluster B one of D. saccharalis and one of soil. On the other hand, in cluster C were that B. microplus and one of soil. While cluster D was integrated by the S. frugiperda, M. murinus and S. piceifrons isolates. Implications. The determination of the genetic diversity between Metarhizium isolates obtained from insects and agroecosystems, generates a contribution on the habitat that will allow the development of strategies to carry out an adequate biological control of pest insects. Conclusion. The analyzes using the RAPD markers indicated that there is a genetic diversity among the Metarhizium isolates collected from different insects and agroecosystems.

Asparagus officinalis L. is a crop associated with arid and dry environments of arid deserts; its tender product is considered a gourmet food for its exclusive consumption and its high prices. Among the main attributes of this vegetable are being a product low in calories, fat and cholesterol, with a high content of vitamin C, as well as rich in potassium and calcium phosphate. The indiscriminate use of synthetic fertilizers in agricultural crop production systems, as well as the increasing dependence, they cause deterioration of the physical and chemical properties of the soil, in addition have a variable impact on the composition and functions of the soil microbiota. Under indigenous area “Seris” in Sonora desert conditions (salinity and high °C), var. ‘Early California’ of asparagus was biofertilized with Bacillus amyloliquefaciens (Ba) as a halo-PGPB and chitosan (QUI) to evaluate nutritional value and yield-production. Results showed that Ba and QUI in the vegetative period increased the emergence rate (≥15%), nitrates in sap (≥10%), fresh and root weight and crown (≥25%); significant values in its subsequent production stage of shoots for human consumption (proximal values such as protein (≥33%), and carbohydrates (≥20%), in addition to K+ (≥9%) and Vit C (≥15%) compared with the control, were obtained. These results express the possibility of using Bacillus amyloliquefaciens as a halo-PGPB and chitosan as a biofertilizer of marine origin in asparagus under Sonora desert conditions.

ABSTRACT: Strawberry guava (Psidium cattleyanumm Sabine) is a species native to southern Brazil which exhibits significant potential for economic exploitation. The objective of this study was to evaluate the growth response of strawberry guava subjected to liming and phosphate fertilizer in pre-planting. The treatments consisted of four lime levels: 0; 33.3; 66.6 and 100 % of the dose needed to increase the pH in water to 6.0, and four phosphorus (P) doses: 0; 83.3; 166.6 and 250 kg ha–1 of P2O5. Plant growth parameters were evaluated for three years. In the years 2018 and 2019, the mineral composition of leaves, photosynthethic pigment indices and mycorrhizal colonization on strawberry guava roots were measured. Liming and phosphate fertilizer altered neither plant growth nor the photosynthetic pigment indices and there was no interaction between the factors studied and the remaining variables evaluated. However, liming promoted increases in the Ca and Mg shoot content, and the phosphate fertilizer increased the levels of shoot P in the third year of growth. Mycorrhizal colonization was stronger when the P soil levels were low, which could explain the absence of response to phosphate fertilization on plant growth for the first three years after planting.

Background. The farmer and his family member are the main actors in the decision-making process for production unit operation (PU), due to the extensive knowledge they have about the production strategies and dynamics. Objective. Analyze the main factors that intervene in the making and construction of decisions for PU operation in dry tropic conditions. Methodology. The information was obtained through a structured survey to farmers of 61 PU of dual-purpose livestock (DP). The PUs were stratified based on the number of Total Livestock Units (TLU): Stratum 1 = UP of ≥ 5 and ≤ 43 TLU (E1), Stratum 2 = PU of ≥ 44 and ≤ 87 TLU (E2) and Stratum 3 = UP with more than 88 TLU (E3). The work consists of three sections: i. an analysis of the activity current situation (structural and socioeconomic), using descriptive statistics and budgets by activity; ii. an analysis of the PU structural changes from 2008-2013-2018 and, iii. an analysis using the Likert Scale of the farmers opinions and objectives on the activity. Results. PUs are characterized by the small families presence, with 58-year-old farmers (65% have primary and secondary education). The main income (81.44%) comes from livestock sale and although higher income is observed in large PUs, the unit margin per ha-1 and cow-1 is higher in small PUs. The participation of the family is fundamental in the decision-making process and the main objective of the farmer is the well-being of the family group, care of the environment in which they develop and maintaining the PU structure. Smaller PUs are dynamic and enthusiastic about structural changes. Implications. The work set the guidelines of the PU and identified the factors that intervene in the decision-making process, the viability, dynamics and permanence of livestock in the dry tropics. Conclusion. The family is essential to help for the farmer in the decision-making process. mainly in the health and nutrition of the herd, as well as in the sale and commercialization of products and, the maintenance of the structure of the PU and care of the environment in which they develop is the main objective. Keywords: cattle; dual purpose; dry tropics; family; decision making.

Background: The central area of the state of Veracruz is widely known as one of the regions with the largest hectares dedicated to the production of potato (Solanum tuberosum L.), this is susceptible to different diseases, an strategy of managements is with applications of growth-promoting rhizobacteria that have yielded favorable results in other crops. Objective: To evaluated seven bacterial strains isolated from the rhizosphere of Solanum tuberosum in terms of plant growth promotion (PGPR). Methodology: The isolates belonged to the species: Providencia alcalifaciens, Pseudomonas syringae pv syringae, Serratia marcescens, Serratia liquefaciens (I), Serratia liquefaciens (II), Pseudomonas putida and Serratia ficaria. Biochemical tests were performed such as production of siderophores, solubilization of phosphate, production of indole-3-acetic acid and nitrogen fixation. Results: All the bacterial strains functioned as plant growth promoters, compared to the negative control, particularly the P. syringae pv syringae and S. liquefaciens (I) strains. Implications: The use of these strains represent an alternative to improve the phytosanitary conditions of this crop for the area. Conclusion: Based on the above, we consider that the seven bacterial strains evaluated in this study constitute a promising and environmentally friendly strategy in development of potato crop of Perote Veracruz.

Recientemente se reportó a Curvularia eragrostidis (Ascomycota: Dothideomycetes) como el agente causal de la Mancha Foliar de la Piña (híbrido MD2) en el Pacífico Centro de México. Por lo tanto, se evaluó la efectividad in vitro de cinco fungicidas químicos (System Cu®, Tilt® 250 CE, Volley® 88OL, Tecto 60® y Mancozeb® 80WP) a cuatro concentraciones (1,0%, 0,5%, 0,25% y 0,125%) sobre C. eragrostidis, a través de bioensayos dosis-respuesta. La tasa de crecimiento diaria (TCD) del hongo en el control (sin fungicida) fue de 1,5 cm/día, mientras que los fungicidas Volley® y Tilt®, en las cuatro concentraciones, no permitieron el crecimiento de C. eragrostidis. La TCD más baja para System Cu®, Mancozeb® 80WP y Tecto® 60 se encontró en la concentración al 1,0% con 0,13, 0,0 y 0,39 cm/día, respectivamente. Los porcentajes de inhibición del crecimiento micelial (%ICM) para Volley® y Tilt® 250 CE fueron del 100% en todas las concentraciones evaluadas. Para System Cu®, Mancozeb® 80WP y Tecto® 60, el %ICM osciló en un rango de 65,2% (0.125%) – 78, % (1,0%), 62,9% (0,125%) – 100,0% (1,0%) y 57,0% (0,125%) – 62,0% (1,0%), respectivamente. Un modelo Probit sugirió una concentración efectiva media (CE50) de 0,025%, 0,067% y 0,076% para System Cu®, Mancozeb® 80WP y Tecto® 60, respectivamente. En conclusión, los fungicidas Volley® y Tilt® son altamente efectivos contra C. eragrostidis; por otra parte, se reportan por primera ocasión las CE50 para System Cu®, Mancozeb® 80WP y Tecto® 60 contra C. eragrostidis.

ABSTRACT The philodendron is a plant with a high sales price, however, in Mexico there is not enough plant material available for the producers of this ornamental. Therefore, the objective of this research was to establish an in vitro aseptic culture of philodendron, for this, the effect of fungicides and bactericides applied from the transplantation of mother plants to the production and harvest of explants (axillary shoots) for in vitro establishment was evaluated. Two experiments were carried out using MS culture medium; in the second, silver nanoparticles (AgNPs) were added to the culture medium. Both experiments were established in a completely randomized experimental design. It was observed that with the joint action of the sanitizing products in the treatment of mother plants and in the disinfection process, as well as the addition of AgNPs to the culture medium, it was possible to establish an aseptic culture of philodendron. Results show that 2 g L-1 of Agry-Gent Plus 5000® plus 2 g L-1 of Prozycar® in the treatment of mother plants was the one generated the highest percentage of aseptic explants (25.71%) in the first in vitro establishment, while, in the second experiment, the same products plus the addition of AgNPs to the culture medium for seven days generated 100% aseptic explants. The contaminants identified were yeasts, Aspergillus sp. and Penicillium sp.

Climate change can cause imbalances in plants. Baccharis trimera is a specie usually found in harsh conditions and has medicinal and agricultural properties. Thus, this study aimed to evaluate the biochemical and physiological responses of this plant under water restriction (WR) levels. B. trimera samples were identified and collected in Erechim/RS and propagated in a greenhouse. When acclimated, they were subjected to 0, 25, 75 and 100% WR, determined according to the water saturation in the soil by capillary action. After 30 days of treatment, the physiological responses: growth, and fresh and dry biomass; and the biochemical responses: activity of superoxide dismutase (SOD), guaiacol peroxidase (GP) and ascorbate peroxidase (APX) enzymes, proline, protein and hydrogen peroxide content, and lipid peroxidation, were determined. Data were submitted to regression analysis and Pearson correlation. The WR of 27.37%, on average, induced an increase in physiological parameters, but the root growth was impaired in conditions above 50% of WR. With the increase in WR there was an increase in the activity of SOD in the shoot and APX in the root. In low WR conditions, proline contents were maintained. Therefore, with low levels of WR, around 27%, B. trimera has increase in root growth and root and shoot biomass. Proline, and SOD and APX activity are a pathway that scavenging the stress generated by WR on B. trimera.

From a cultural point of view, Maize is the most important crop in Mexico, and is also an essential food in the Mexican diet. This study aimed to evaluate the physical and chemical characteristics of maize grain and their influence on the quality of dough and tortillas produced with three native maize cultivars from western Mexico. Physical, structural, and chemical characteristics of the grain were evaluated, including hectolitric weight, 100-grain weight, flotation index, grain structure, grain color, pedicel, pericarp, germ, and floury endosperm, vitreous endosperm, ethereal extract, and protein. Nixtamal and tortilla quality include nixtamal moisture, dough moisture, freshly made tortilla moisture, total soluble solids, pericarp remnant, dough yield, and hot tortilla yield. In general, statistical differences (p ≤ 0.05) were found in almost all variables analyzed. The principal component analysis (PCA) showed that two principal components (PCs), described approximately 79% of the variation, and a positive correlation between the characteristics of freshly made tortilla moisture (FMTM), dough yield (DY), and nixtamal moisture (NM), as well as dough moisture (DM) and hot tortilla yield (HTY). Future studies on these and other native maize cultivars of western Mexico must be conducted to assess the physicochemical and phytochemical characteristics of maize grains that may be useful for food and pharmaceutical applications, contributing to the conservation, propagation, and use of natural and ancient resources.

The objective of this study was to evaluate the inclusion of oregano essential oil (OEO) as a phytogenic feed additive in the diet of lambs on the productive performance, ruminal pH, ammoniacal nitrogen production, volatile fatty acids, nitrogen balance, carcass yield, backfat thickness, loin eye (Longissimus dorsi) area, shelf life, and antioxidant activity of the meat. Thirty-nine Suffolk × Hampshire lambs (19 ± 3.7 kg live weight) were used in a completely randomized design with three treatments (n = 13) consisting of 0, 0.02, and 0.04% OEO in the diet. The inclusion of OEO in the diet did not affect (p > 0.05) the productive performance due to the treatments; similarly, no differences (p > 0.05) were observed in the ruminal variables and nitrogen balance. Backfat thickness and loin eye area had similar results (p > 0.05), and the antioxidant activity in meat was improved (p < 0.05) with the inclusion of OEO. Shelf life and crude protein content increased (p < 0.05) with the inclusion of OEO in the diet and with the passing of storage days. Dry matter was affected (p < 0.05) by the storage time, with a decrease observed on day 24. pH, ether extract, and ash were not affected (p > 0.05). It is concluded that the productive performance, ruminal variables, nitrogen balance, loin eye area, backfat thickness, and carcass yield were not affected by the inclusion of OEO. However, crude protein remained stable and antioxidant activity improved, increasing the shelf life of lamb meat.

This study set out to assess the nutritional status of peach trees in the commercial peach-growing region of Pelotas, Rio Grande do Sul. The sample includes 65 peach orchards of the Maciel, Granada, Esmeralda, and Sensação cultivars in the municipalities of Pelotas, Canguçu, and Morro Redondo during the 2018 agricultural cycle. After drying and grinding the leaf samples for an analysis of their nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), boron (B), copper (Cu), iron (Fe), manganese (Mn), and zinc (Zn) content, the results were presented in frequency distributions divided into classes based on the nutrient requirements indicated for the crop in the region, in addition to the correlations between the nutrients. Greater deficiencies were observed in nitrogen, copper, iron, and zinc content. However, potassium content was found in the “above normal” class for most of the samples, and there were correlations between P/Ca, P/Cu, Ca/P, Ca/Mg, and Ca/B. An insufficient use of the tools to assess the nutritional status of the orchards was observed, especially the leaf diagnosis, which led to the inappropriate use of fertilizers and the consequent nutrient imbalance in the plants.

Para pessegueiros produzidos na região sul do Brasil ainda são escassas as informações sobre a influência da adubação potássica sobre a qualidade dos frutos. Deste modo, o presente trabalho teve como objetivo avaliar os atributos físico-químicos e compostos bioativos dos frutos de pessegueiros submetidos a diferentes doses de potássio aplicadas no solo por três safras consecutivas. O experimento foi realizado estudando a cultivar Sensação em um pomar comercial no município de Morro Redondo, RS – Brasil, durante as safras de 2016, 2017 e 2018. Os pessegueiros da cultivar Sensação foram adubados com potássio (K) nas doses de 0, 40, 80, 120 e 160 kg ha-1 de K2O na forma de cloreto de potássio, aplicadas na superfície do solo. Após a colheita foram determinados os teores de sólidos solúveis (SS), acidez titulável (AT), relação SS/AT, pH, coloração da polpa, firmeza da epiderme e da polpa, teor de carotenoides totais, compostos fenólicos totais e atividade antioxidante. A firmeza da epiderme, a relação SS/AT e a concentração de carotenoides dos pêssegos responderam à adubação potássica, mas apenas em alguns ciclos de produção. Os parâmetros de coloração, firmeza da polpa, sólidos solúveis, pH do suco, fenóis totais e atividade antioxidante dos pêssegos não alteraram em decorrência da aplicação de potássio ao solo.

O objetivo do trabalho foi determinar a época de colheita, os principais componentes de rendimento e atributos de qualidade físico-química de cultivares de pessegueiro produzidos em Dois Vizinhos, PR. O trabalho foi realizado no setor de Fruticultura da Universidade Tecnológica Federal do Paraná, Campus Dois Vizinhos. Obteve-se em duas safras agrícolas, 2016 e 2017, as datas de início de colheita, os principais componentes de rendimento e a produtividade estimada, cor de fundo da epiderme, firmeza de polpa, teores de sólidos solúveis (SS) e acidez titulável (AT), bem como a relação SS/AT (ratio) de 17 cultivares de pessegueiros. O delineamento experimental foi de blocos ao acaso com quatro repetições de uma planta por unidade experimental, num esquema bifatorial 17 x 2 (cultivares x anos de cultivo). Os frutos das cultivares Aurora-1, Bonão, Douradão, Leonense, Ouromel, Rubimel e Zilli amadureceram mais cedo, enquanto os de Eldorado e BR-1 foram os últimos a amadurecer. As cultivares Bonão, Charme e Eldorado foram as mais produtivas. Eldorado produziu o maior calibre de frutos e Bonão produziu o maior número de frutos por planta. As cultivares BR-1 e Eldorado produziram os frutos mais doces e Leonense, os mais ácidos. A safra de 2016 proporcionou maior produtividade, com frutos de maior calibre e firmeza da polpa.

Background: anthracnose (Colletotrichum gloeosporioides) is an important disease in mango (Mangifera indica) due to its worldwide distribution and inducting of severe epidemics in vegetative and reproductive states, causing significant losses. In nature, plants produce defense mechanisms to protect themselves from biotic and abiotic factors by increasing the synthesis of secondary metabolites and enzymes involving processes such as the accumulation of phenolic compounds, β-1, 3-glucanases and chitinases. Objective: in the present work, the increase in the accumulation of phenolic compounds and enzymes related to pathogenesis β-1, 3-glucanases and chitinases was evaluated as a function of inducers of systemic resistance acquired: acibenzolar-S-methyl, salicylic acid and sodium phosphonate (phosphite). Methodology: the applications of treatments were initiated when the plants were approximately 2 years old (6 months of acclimation), the treatments were applied via foliage, the foliage sampling for the enzymatic analysis was performed taken at 0, 5, 10, 20, and 30 days after inoculations (dai) and the variables evaluated were: phenolic compounds concentration, enzymatic activity of β-1,3-glucanasess (GLU) and chitinases (CHI) by chromatographic methods, also the incubation period, incidence, severity were evaluated. Results: analysis of variance, growth dynamics and correlation showed that those treatments where a resistance inducer was applied had significantly lower incidence and severity levels than the control, as well longer incubation periods. The dynamics of phenolic compound concentration and enzymatic activity were similar in all treatments except for control, observing peaks at 5 and 20 days after application. In addition, a significant correlation between the variables: area under the progress curve of the accumulation of phenolic compounds and activity of β-1, 3-glucanases and chitinases with the anthracnose incidence, severity and incubation period could be observed. Implications: in future studies it is recommended to analyze the behavior of treatments in multiple cultivars. Conclusion: these results contribute to the mango agronomic management in the region as precedent in the search to low environmental impact alternatives for diseases management, also contributing to the determination of disease’s etiology.

Background: mango is cultivated in most tropical and subtropical regions of the world, it is estimated that there are more than a thousand cultivars, so its regional characterization represents a priority in countries such as Mexico, which holds the first place for export. Objective: the objective of the present study was to identify biochemical characteristics (photosynthetic pigments, type and proportion of carbohydrates) of eight recently introduced cultivars and two new selections in Mexico. Methodology: by spectrophotometric analysis, the concentrations of total sugars, reducing sugars and starches were evaluated, as well as the content of chlorophylls a, b and carotenoids of the cultivars 'Nam Doc Mai', 'Rosygold', 'Mallika', 'Ivory', 'Alphonse', 'Neelum', 'Fairchild', 'Kesar', 'Ataúlfo Diamante' and 'Ataúlfo Zafiro'. Results: in the case of total and reducing sugars, the cultivars ‘Kesar’, ‘Nam Doc Mai’, ‘Ivory’, ‘Mallika’ and ‘A. Zafiro' (0.42, 0.34, 0.34, 0.33, and 0.32 mg*g-1 pf-1) presented the highest values (respectively), the starch content was very heterogeneous and 'Rosygold' (0.36 mg*g-1 pf-1) was identified as cultivar with higher levels. The results showed ‘Ivory’ (0.64, 0.59, 0.27 mg*g-1 pf-1) as the cultivar with the highest concentration of chlorophyll a, b and carotenoid photosynthetic pigments respectively. Based on the correlation analysis (r), a certain dependence could be observed between total and reducing sugars (r= 0.70), total sugars and starches (r= 0.76), reducing sugars and starches (r = 0.79). In the case of photosynthetic pigments, a close relationship between chlorophylls a, b and carotenoids was identified (r= 0.99); In the photosynthetic carbohydrate / pigment interaction, a significant correlation was observed between total sugars and chlorophylls a (r= -0.80), b (r= -0.80) and carotenoids (r= 0.82). The close relationship found between reducing sugars and chlorophyll a (r= 0.60), chlorophyll b (r= 0.99) and carotenoids (r= 0.99) stood out. Implications: it is necessary to continue the study in floral and fruiting stages to have a complete profile of the cultivars. Conclusion: these results will contribute in future agronomic studies of these varieties in the region in order to analyze their relationship with parameters such as yield and nutritional content of fruits.

A diagnose foliar é uma importante ferramenta para a avaliação do estado nutricional da macieira. As concentrações dos nutrientes nas folhas variam em função da época de amostragem e em resposta às adubações. O objetivo deste trabalho foi avaliar o efeito da adubação nitrogenada e potássica sobre o vigor e a composição mineral das folhas da macieira em duas épocas de amostragem. O experimento foi conduzido no período de 1998 a 2006, no município de São Joaquim, SC. Consistiu de um fatorial com doses de N e K aplicadas anualmente ao solo (zero, 50, 100 e 200kg/ha de N e de K O). A análise química foi realizada em folhas coletadas na época padrão de amostragem, 15 de janeiro a 15 de fevereiro, e também antecipadamente durante a segunda quinzena de novembro nos anos agrícolas 2004/05 e 2005/06. O vigor das plantas foi avaliado por meio das medições do perímetro do tronco. As concentrações dos macronutrientes nas folhas foram alteradas, principalmente pela adubação nitrogenada, que promoveu o incremento das concentrações de N, Ca e Mg e a redução das concentrações de K e P. A adubação potássica reduziu as concentrações foliares de Mg e de Ca. O vigor das plantas foi influenciado positivamente pela adubação nitrogenada. Os teores dos nutrientes de folhas coletadas em novembro apresentaram boa correlação com aqueles de folhas coletadas na época padrão de amostragem, em janeiro/fevereiro.

Objetivou-se com este trabalho o estudo de diferentes modelos matemátcos para caracterizar as disponibilidades térmicas no período hibernal e prever a data inicial da brotação do cultvar de videira Vitis vinifera Cabernet Sauvignon. O trabalho foi realizado a partr de uma série histórica (1984-1993) de dados climátcos e de dados fenológicos do Banco Atvo de Germoplasma, ambos da Embrapa Uva e Vinho, em Bento Gonçalves, RS. Os acúmulos de frio foram quantfcados com o uso de nove métodos: horas de frio iguais ou inferiores a 7,2°C e a 10°C; modelo Dinâmico; e modelos de Utah e Carolina do Norte em suas versões originais, modifcados para altas temperaturas e adaptados para as condições da Serra Gaúcha. No estudo da série histórica, os melhores resultados (resíduos menores) foram obtdos pelos modelos de Utah e Carolina do Norte adaptados para as condições climátcas da Serra Gaúcha.

O fósforo faz parte de numerosos compostos orgânicos no metabolismo das plantas, como nucleotídeos e fosfoproteínas além de participar do metabolismo e armazenamento de energia. O objetivo do presente trabalho foi avaliar a resposta de pessegueiros cv. Sensação a adubação fosfatada e estabelecer o nível crítico deste nutriente no solo e nas folhas. O experimento foi conduzido nos ciclos 2016 e 2017 em um pomar comercial localizado no município de Morro Redondo/RS – Brasil. O delineamento experimental foi de blocos ao acaso com quatro repetições. Os pessegueiros foram adubados com doses crescentes de fósforo (P), sendo estas, 0, 20, 40, 60 e 80 kg ha-1 de P2O5 na forma de superfosfato triplo. Nos dois ciclos avaliados foram coletadas amostras de solo na camada de 0-20 cm e de folhas para determinação dos teores de minerais. Os dados obtidos, foram submetidos a análise de variância pelo teste F (P < 0,05), e quando os efeitos foram significativos, ajustadas as equações de regressão. A aplicação de P aumentou os teores deste nutriente no solo. Os teores foliares de P não foram afetados pela adubação, bem como a produtividade e os componentes de rendimento. Sendo assim, não foi possível estabelecer um nível crítico de P no solo e nas folhas de pessegueiros. Em solos onde os teores de P são classificados como médios e acima disso, não há a necessidade de se aplicar este nutriente.

Objetivou-se com este trabalho avaliar em laboratório a seletividade de nove produtos fitossanitários utilizados na cultura do pessegueiro sobre as fases de ovo e pupa dos predadores Chrysoperla externa e Coleomegilla quadrifasciata. Os ensaios consistiram da aplicação direta dos agrotóxicos sobre ovos e pupas dos predadores e avaliação de efeitos subletais na fertilidade e fecundidade dos adultos emergidos. Para ovos, os produtos fitossanitários foram classi?cados em função dos efeitos na redução da porcentagem de eclosão de larvas, e para pupas em função do efeito total, conforme a escala de toxicidade proposta pela International Organization for Biological and Integrated Control (IOBC). Todos os produtos fitossanitários (dosagem utilizada) foram inócuos (classe 1) aos ovos de C. externa, entretanto, abamectina (80) e cobre + cálcio (1%) foram considerados levemente nocivos (classe 2) às pupas. Nos bioensaios com C. quadrifasciata, abamectina (80), deltametrina (40) e malationa (150) foram classificados como levemente nocivos (classe 2), enquanto fenitrotiona (100) apresentou-se como moderadamente nocivo (classe 3) aos ovos do predador; para a fase de pupa, abamectina (80), fenitrotiona (100) e malationa (150) foram nocivos (classe 4). Os produtos Azadiractina (1%), clorantraniliprole (14), deltametrina (40), cobre + cálcio (25% + 10%) e enxofre + cálcio (3,5 Ba) são inócuos (classe 1) aos ovos e pupas de C. externa e C. quadrifasciata, e assim devem ser priorizados em pulverizações visando ao controle de pragas no MIP pessegueiro.

Abstract: Fruit flies are the main pests of fruit growing in Brazil. They have been managed predominantly with the use of insecticides applied as cover spray and or/as toxic baits. Currently, the trend of management strategies is toward the adoption of methods that cause the lowest environmental impact in large areas. In this context, biological control is an excellent option to be used together with other management strategies, such as sterile insects, because it leaves no residues, does not disturb nontarget pests, and can be permanent if the natural enemy establishes itself in the field. This review paper addresses the current knowledge on the biological control of fruit flies in Brazil, highlighting the great biodiversity of its natural enemies, especially parasitoids, its biology and ecology. The classical biological control programs in Brazil are also reported, from the introduction of Tetrastichus giffardianus (Hymenoptera: Eulophidae), in 1937, to control Ceratitis capitata (Diptera: Tephritidae), to that of Fopius arisanus (Hymenoptera: Braconidae), in 2012, to control Bactrocera carambolae (Diptera: Tephritidae). Finally, the obtained advances are pointed out, as well as the main bottlenecks and perspectives for the effective use of biological control programs against fruit flies.

Currently, urban agriculture is recognized worldwide as an important economic activity, which contributes to improving the food, income and the environment of the population living in cities. In Mexico, despite the evident social, economic and environmental benefits of urban agriculture, as well as the existence of successful examples in some cities in this country, most of the population does not participate. The current investigation addressed the case of the Network of Urban and Periurban Agriculture (RAUP) in Xalapa, Veracruz, with the aim of analyzing the technical-productive and socioeconomic limitations to the adoption of urban agriculture, from the perspective of the members who practice this activity in their homes and those who participate sporadically in the network, but have still not implemented it. 25 questionnaires were applied to active members and 10 to those who do not practice this activity. Data from the survey was analyzed using descriptive statistics, with the program Excel. Two types of RAUP participants agreed that the main constraints are socioeconomic, for example lack of space in homesteads and limits on people‘s free time, both of which are related to urban lifestyle; whereas technical-productive limitations were not considered relevant.