Volumen 115 | Número 02

Los sistemas de producción de carne y leche bovina en la provincia de Buenos Aires ¿conservan los nutrientes del suelo?

2020-07-02T01:09:28Z

Articulo Bovine milk and meat systems production in the Province of Buenos Aires conserve soil nutrients? Revista de la Facultad de Agronomía; vol. 115, no. 2 Una producción agropecuaria sustentable debe ser compatible con la conservación de los recursos naturales, entre ellos el suelo. Un objetivo necesario es la conservación de los nutrientes del suelo, lo cual está influenciado por el modelo de producción realizado. En Buenos Aires existen escasos estudios que analicen el balance de nutrientes de la producción de carne y leche bovina, a pesar que ocupa el 54% de su superficie. En parte esto se debe a que se asocia a la ganadería con la mejora en la fertilidad edáfica, aunque esto puede estar enmascarando una disminución del reservorio de nutrientes. En este trabajo se evaluó el impacto de la producción de carne y leche en la conservación de los nutrientes del suelo en la provincia de Buenos Aires. Se analizó el balance de nutrientes (N, P, K, Ca, S) en la producción de leche (PL) y carne (PC). Se encontró que PL es más extractiva por hectárea en todos los nutrientes que PC. En ambas actividades el balance de nutrientes fue positivo en N y P y negativo en el resto de los elementos, siendo PC el mayor responsable en los excesos y déficit totales. La fijación biológica fue la principal entrada en N y la fertilización en P. Los excesos de N se observaron en toda la provincia mientras que en P sólo en la zona con mayor presencia de tambos e invernada.; A sustainable agricultural production must be compatible with the conservation of natural resources, including soil. A necessary objective is the conservation of soil nutrients, which is influenced by the production model made. In Buenos Aires there are few studies that analyze the nutrient balance of bovine meat and milk production, despite occupying 54% of its surface. In part this is because livestock is associated with improvement in soil fertility, although this may be masking a decrease nutrient reservoir. In this paper the impact of the production of meat and milk in the conservation of soil nutrients in the province of Buenos Aires was evaluated. The nutrients balance (N, P, K, Ca, S) was analyzed in milk (PL) and meat production (PC). PL was more extractive per hectare in all the nutrients than PC. In both activities nutrient balance was positive in N and P and negative in K, Ca and S. PC generated the major total excesses and total deficit. Biological fixation was the main entrance in N and fertilization in P. N excess were observed throughout the whole province while in P only in the area with more dairy farms and fattening cattle. To achieve milk and meat productions sustainability replenishing K, Ca and S is need across all the province and P in much of the same.

Eficacia y selectividad de mezclas de herbicidas en el cultivo de mandioca

2019-11-13T20:02:47Z

Articulo Efficacy and selectivity of herbicides mixtures in cassava Revista de la Facultad de Agronomía; vol. 115, no. 2 El objetivo de este trabajo fue evaluar la eficacia y la selectividad de las mezclas de herbicidas hechas en el tanque fumigador aplicados a la mandioca. El diseño experimental utilizado fue de bloques aleatorizados con cuatro repeticiones. Los tratamientos estuvieron constituidos por las aplicaciones de los herbicida clomazone (1.260 g ha-1), sulfentrazone + clomazone (1260 + 600 g ha-1), clomazone + diclosulam (1260 + 35 g ha-1), clomazone + s-metolaclor (1260 + 1440 g ha-1), metribuzin (480 g ha-1), metribuzin + sulfentrazone (480 + 600 g ha-1), metribuzin + diclosulam (480 + 35 g ha-1) y el metribuzin + s-metolaclor (480 + 1440 g ha-1), además de dos testigos, una carpida con azada y otra no carpida. En base de los datos obtenidos, podemos concluir que la mezcla de clomazone + sulfentrazone (1260 + 600 g ha-1) fue el más efectivo y selectivo al cultivo. Las mezclas clomazone + s-metolaclor (1260 + 1440 g ha-1) y el metribuzin + sulfentrazone (480 + 600 g ha-1) demostraron un buen potencial para la eficacia y selectividad equivalente al producto registrado clomazone aplicados en forma aislada. El metribuzin (480 g ha-1) y el metribuzin + s-metolaclor (480 + 1440 g ha-1) fueron poco efectivos en el control de las malezas. Las mezclas de herbicidas con diclosulam, aunque son muy efectivas en el control de las malezas, no son selectivas para la mandioca.; This assay was labored aiming to test the effectiveness and selectivity of pre-emergence herbicides mixtures applied in cassava crop. The assay design was randomized blocks with four replications. The treatments consisted of the applications of the following herbicides: clomazone (1260 g ha-1), clomazone + sulfentrazone (1260 + 600 g ha-1), clomazone + diclosulam (1260 + 35 g ha-1), clomazone + S-metolachlor (1260 + 1440 g ha-1), metribuzin (480 g ha-1), sulfentrazone + metribuzin (480 + 600 g ha-1), metribuzin + diclosulam (480 + 35 g ha-1) and S-metolachlor + metribuzin (480 + 1440 g ha-1), and two controls, one weeded and a non-weeded. Based on the obtained data, it can be concluded that the mixture of clomazone + sulfentrazone (1260 + 600 g ha-1) was more efficient and selective to cassava crop. Mixtures of clomazone + S-metolachlor (1260 + 1440 g ha-1) and metribuzin + sulfentrazone (480 + 600 g ha-1) showed good potential for effectiveness and selectivity, equivalent to the product registered clomazone (600 g ha-1). Metribuzin (480 g ha-1) and metribuzin + S-metolachlor (480 + 1440 g ha-1) were inefficient in controlling weeds. Herbicides mixtures with diclosulam, although highly effective in controlling weeds are not selective to the cassava crop.

Motivación e integración curricular en fitopatología: Diagnóstico y propuestas de mejora

2020-04-30T18:25:15Z

Articulo Motivation and curricular innovation improvement in phytopathology. Diagnosis and proposals Revista de la Facultad de Agronomía; vol. 115, no. 2 El artículo aborda una innovación didáctica que se diseñó con la finalidad de incrementar el nivel de motivación y autoconfianza de los estudiantes en el desafío y esfuerzo por aprender fitopatología y, asimismo, procura mejorar la construcción de conocimientos integrados en los contenidos de la disciplina. La innovación pretende contribuir al desarrollo de habilidades y actitudes relevantes para el desempeño profesional en el sector agropecuario y forestal. La propuesta surgió a partir de problemáticas observadas que se manifestaban en actitudes de desinterés o falta de motivación para el estudio por parte de los estudiantes y en dificultades para lograr la articulación de saberes relacionados a los contenidos de la asignatura. Asimismo, se partió de asumir que la enseñanza constituye una variable crítica en la mejora de la motivación y en la calidad del aprendizaje que construyen los estudiantes. Para comprender esta problemática se realizó un relevamiento de información a través de entrevistas a docentes del curso y encuestas a estudiantes llevando a cabo un análisis y triangulación de ambas perspectivas. Se diseñó una innovación a implementarse desde el inicio del curso con el desarrollo del primer trabajo práctico y con una propuesta de integración curricular de resolución a lo largo del cuatrimestre. La primera actividad práctica se propone para ser realizada en el medio productivo propiciando situaciones didácticas en las que los estudiantes aborden problemáticas fitopatológicas reales. Asimismo, se pretende que el trabajo de integración favorezca la construcción de relaciones conceptuales significativas entre contenidos de la fitopatología considerados de relevancia así como el aprendizaje en la dimensión procedimental y su articulación.; This article presents a didactic innovation that aims at increasing the level of motivation and self confidence of students in the face of the challenge and effort of learning phytopathology in the School of Agrarian and Forest Sciences of the National University of La Plata. In addition, it seeks to improve the construction of knowledge integrated to discipline contents. It also intends to contribute to the development of relevant skills and attitudes for professional activity in agrarian and forest sectors. The project stems from observed problems made evident through attitudes of disinterest and lack of motivation to studying of the students and in the difficulty to achieve the articulation of knowledge related to the contents of the subject. Moreover, teaching is assumed to be a critical variable in the improvement of motivation and the quality of learning attained by students. To understand the research problem, data collection was done through the use of interviews and surveys addressed to the teachers and students of the course respectively. Analysis of data was carried out considering a triangulation of both perspectives. The implementation of the innovation is proposed from the beginning of the course in the development of the first practical work and with a project of curricular integration to be developed throughout the term. The first practical activity is proposed in the productive environment encouraging didactic situations in which students work with real phytopathology issues. The integration work intends to construct meaningful conceptual relationships between phytopathology contents which are considered of relevance as well as learning in the procedural dimension and its articulation.

Producción, almacenamiento en el suelo y viabilidad de las semillas de Nothofagus dombeyi, N. obliqua y N. alpina (Nothofagaceae) en un bosque templado del noroeste de la Patagonia argentina

2019-11-13T20:02:42Z

Articulo Production, soil storage and viability of Nothofagus dombeyi, Nothofagus obliqua and Nothofagus alpina (Nothofagaceae) seeds in a temperate forest from Northwestern Patagonia of Argentina Revista de la Facultad de Agronomía; vol. 115, no. 2 La producción, el almacenamiento en el suelo y la viabilidad de las semillas de Nothofagus dombeyi ((Mirb.) Oerst., coihue), Nothofagus obliqua ((Mirb.) Oerst., roble pellín) y Nothofagus alpina ((Poepp. & Endl.) Oerst., raulí) fueron analizadas en cuatro rodales de la cuenca del lago Lácar (Parque Nacional Lanín). Entre 2001 y 2003, N. dombeyi produjo el 86,4 % de las semillas y exhibió una fecundidad individual hasta 44 veces mayor a la de las otras especies, que se vincularía al menor tamaño de la semilla. La producción aumentó en los rodales con árboles de tamaño mayor. Los árboles produjeron hasta 47 veces más semillas durante el segundo y tercer periodo anual, un fenómeno sincronizado que aumentaría la eficiencia reproductiva. Las diferencias interespecíficas en el tamaño de la semilla y la fecundidad fueron compatibles con el temperamento de los árboles. La estructura espacial de las semillas caídas fue agrupado; sin embargo, la mayor producción redujo la intensidad del agrupamiento lo que disminuiría la mortalidad durante el autorraleo. La correlación positiva entre la lluvia y el banco del suelo y el cociente muy bajo de la abundancia de semillas asociada a estos procesos, reflejaría el papel clave de la producción sobre la acumulación de semillas. La tasa máxima de germinación fue 0,12 %. Estas especies conformarían en el suelo un banco transitorio de verano, cuyas semillas emergerían en la primavera inmediata a la diseminación. La reducida longevidad de las semillas en el suelo restringiría el uso de este reservorio para la conservación y silvicultura de este valioso ecosistema.; Production, soil storage and viability of seeds of Nothofagus dombeyi ((Mirb.) Oerst., coihue), Nothofagus obliqua ((Mirb.) Oerst., roble pellín) and Nothofagus alpina ((Poepp. & Endl.) Oerst., raulí) were analysed in four forest stands within the lake Lácar watershed (Lanín National Park). Between 2001 and 2003, N. dombeyi accounted for 86.4 % of the seed rain and exhibited an individual fecundity up to 44-times larger than that of the other species, probably as a response to a trade-off related to a smaller seed weight. Seed production increased in mature stands possibly due to the presence of larger trees. Regardless species, trees produced up to 47-times more seeds during the second and third annual period, a synchronous masting that would increase reproductive efficiency. Interspecific differences in seed weight and fecundity were consistent with tree temperament. Although fallen seeds were spatially clumped, grouping intensity decreased with fertility, and consequently a plant mortality reduction is expected during self-thinning. Both, the positive correlation between seed rain and storage and the low ratio of seeds abundance related to these processes, would reflect the key role of production in soil accumulation. In all species, maximum germination rate was 0.12 %. These species would develop a summer transient soil bank with seeds strictly emerging during the spring immediate to dispersal. Even though seeds accumulate extensively into the soil, only those emerging rapidly probably constitute a potential seedlings source. The reduced seed longevity within the soil profile would imply a limited significance for tree regeneration, restricting the use of the seed pool for conservation and management of this valuable ecosystem.

Los profesores que conformaron la historia de la Cátedra de Botánica de la Facultad de Agronomía de la Universidad Nacional de La Plata (1883-1994)

2019-11-13T20:02:40Z

Comunicacion The professors who formed the history of the Chair of Botany of the Facultad de Agronomía de la Universidad Nacional de La Plata (1883-1994) Revista de la Facultad de Agronomía; vol. 115, no. 2 El objetivo del trabajo fue recordar el pasado para aprender y vivir para el futuro. Para alcanzarlo se visitaron y consultaron numerosas personas e instituciones que brindaron su conocimiento y la bibliografía que poseían. Con los datos obtenidos se fue estructurando un relato escrito de una parte de la historia de la Facultad de Agronomía de la Universidad Nacional de La Plata y una breve historia biográfica de los diecisiete Profesores de Botánica que pasaron por ella entre 1883 y 1994, dejando su legado cultural.; The aim of the work was to remember the past to learn and live for the future. In order to achieve this, many people and institutions that provided their knowledge and the bibliography were visited and consulted. With the data obtained was structured a written account of a part of the history of the Faculty of Agronomy of the National University of La Plata and a brief biographical history of the seventeen Professors of Botany who passed through it between 1883 and 1994, leaving its Cultural legacy.

Hortas caseiras, plantas medicinais e Universidade Federal da Grande Dourados: trabalho voluntário em diferentes estratos sociais

2019-11-13T20:02:39Z

Comunicacion Home vegetable gardens and medicinal plants promoting voluntary work in different social levels Revista de la Facultad de Agronomía; vol. 115, no. 2 Necessário se faz a junção de esforços interinstitucionais para que se incentive a produção de alimentos para o próprio consumo e de plantas medicinais. Os trabalhos com hortaliças e plantas medicinais fazem parte de projetos de extensão, com oferecimento de Cursos práticos, ministrados nos fundos de quintal de diferentes Instituições. Dentre os inúmeros trabalhos realizados, ou em condução, têm-se 1) UFGD forma horta caseira com idosos; 2) UFGD e TV Morena, em Dourados, ensinam a cultivar hortaliças para combater o estresse de trabalho e melhorar o cardápio familiar; 3) Horta caseira e horto de plantas medicinais como forma de ocupação e de valorização da vida; 4) Horta escolar: a UFGD ensina a valorizar a terra e a melhorar a alimentação; 5) A Universidade e o CMO ensinam a militares e a civis a implantar hortas familiares e hortos de plantas medicinais, para combater a fome e melhorar a renda; 6) A Universidade e as hortas colaboram na erradicação do trabalho infantil; 7) Ensinamentos sobre produção de plantas medicinais em hortos familiares, em Dourados e 8) WORKSHOPS discutem plantas medicinais há 14 anos em Dourados-MS. Dentre os resultados obtidos nos diferentes trabalhos de extensão citam-se (1) a manutenção das hortas e dos hortos de plantas medicinais, para abastecer parte das necessidades da instituição e (2) mostrar aos alunos da UFGD e à sociedade douradense o valor de um trabalho social e da importância da UFGD na prestação de serviço, levando à melhoria do bem estar dos cidadãos.; It is necessary to do a connection of inter-institutional efforts for motivation the production of for own consumption and of medicinal plants. The works with vegetable and medicinal plants made part of extension projects, offering practical courses which were performed at the backyards of different institutions. Among various works, which were performed or are performing, we have: 1) UFGD performs home vegetable gardens with old people; 2) UFGD and TV Morena, in Dourados, teach to cultivate vegetables for combating stress and for improving family’s menu; 3) Home vegetable garden and medicinal plant garden as way of occupation and of valorization of life; 4) School vegetable garden: UFGD teaches to valorize the earth and to improve food; 5) the University and CMO teach militaries and civilians to cultivate home vegetable gardens and medicinal plant gardens for combating hunger and for improving income; 6) The University and the cultivation of vegetable gardens contribute for eradication of child work; 7) Teaching on medicinal plant and home vegetable gardens in Dourados-MS; 8) WORKSHOPS discuss medicinal plants for more than 14 years in Dourados-MS. Among obtained results by differents works of extension, we can cite: 1) the maintaining of vegetable and medicinal gardens for supply part of institution needs and 2) to show to students of UFGD and to Dourados socity the value of a social work and the importance of UFGD in providing service and improving the well-being of citizen.

Avaliação de Pteridium aquilinum (Dennstaedtiaceae) e Urtica dioica(Urticaceae) como alternativas ao equilíbrio populacional de afídeos em cultivos orgânicos no Sul do Brasil

2019-11-13T20:02:38Z

Articulo Evaluation of Pteridium aquilinum (Dennstaedtiaceae) and Urtica dioica (Urticaceae) as alternatives to populational aphid balance in organic crops in southern Brazil Revista de la Facultad de Agronomía; vol. 115, no. 2 A samambaia Pteridium aquilinum L. Kunh (Dennstaedtiaceae) é uma espécie cosmopolita, espontânea, considerada indicadora de solos ácidos, alelopática e utilizada para o manejo de insetos, ácaros e nematóides quando incorporada em extratos e biofertilizantes. A espécie Urtica dioica L. (Urticaceae) ocorre como espontânea no Brasil, sendo utilizada como medicinal, indicadora de solos férteis, hospedeira de inimigos naturais, e aplicada sobre os cultivos na forma de extratos fitoprotetores ou preparados biodinâmicos. Nesse sentido, ressalta-se que a grande maioria das indicações de uso para as duas espécies botânicas citadas referem-se ao conhecimento empírico acumulado, sendo escassos os trabalhos de investigação científica envolvendo a sua bioatividade sobre os agroecossistemas. Nesse sentido, o trabalho buscou avaliar a ação dos extratos aquosos de P. aquilinum (10% p/v) e U. dioica (5% p/v) sobre a repelência, mortalidade, sobrevivência, produção de ninfas e taxa instantânea de crescimento populacional do afídeo Brevicoryne brassicae (Hemiptera: Aphididae) em couve. Simultaneamente ao extrato bruto das plantas, foram avaliadas as diluições 30 e 10%, além da testemunha água destilada e do produto teste AGV Xispa-praga. Os extratos de P. aquilinum resultaram em ação repelente e inseticida, redução da prole e sobrevivência, bem como ri negativa, sugerindo o declínio populacional dos afídeos expostos aos tratamentos. Já os extratos elaborados a partir de U. dioica apresentaram ação repelente, diminuição da prole e da sobrevivência de ninfas. Na análise conjunta dos resultados, as duas espécies avaliadas revelaram-se como estratégias botânicas promissoras para o manejo de afídeos em cultivos orgânicos de brássicas, legitimando as informações advindas do saber popular.; The fern Pteridium aquilinum L. Kunh (Dennstaedtiaceae) is a cosmopolitan species, allelopathic, considered as indicator of acid soils and also used for management of insect populations, mites and nematodes, as incorporated in extracts and biofertilizers. Urtica dioica L. (Urticaceae) is a perennial herb from Europe, introduced in Brazil for medical purposes, growing in nitrogen-rich soils, hostess of natural enemies, when applied on crops as extracts or biodynamic preparations. It's important to note that vast majority of the intended use for these two botanical species, refers to the accumulated empirical knowledge, highlighting that there are few scientific researches involving its bioactivity on agroecosystems. In this sense, this study aimed to evaluate the effect of aqueous extracts of P. aquilinum (10% w / v) and U. dioica (5% w / v) on the repellency, mortality, survival, production of nymphs and instantaneous rate of growth population of the aphid Brevicoryne brassicae (Hemiptera: Aphididae) in kale. Simultaneously to the crude extract of plants, the dilutions of 30 and 10% were evaluated, beyond the distilled water as control and the product AGV Xispa-praga. The P. aquilinum extract resulted in repellent and insecticide action, reduction of the offspring and survival, as well as rinegative, suggesting decline of the aphids populations exposed to treatment. Yet, the extract made from U. dioica showed repellent action, decreasing the offspring and survival of nymphs. In general, the two species studied are considered as promising botanical strategies for managing aphids in organic crops of brassica, legitimizing information coming from the popular knowledge.

Purpureocillium lilacinum LPSC # 876: producción de conidias en cultivos sobre sustratos sólidos y evaluación de su actividad sobre Nacobbus aberrans en plantas de tomate

2019-11-13T20:02:35Z

Articulo Conidial production of Purpureocillium lilacinum LPSC # 876 on solid substrates. Effect on Nacobbus aberrans in tomato plants Revista de la Facultad de Agronomía; vol. 115, no. 2 Purpureocillium lilacinum (Thom) Samson (Luangsa-ard et al.) ha sido reportado para el control del fitonematodo Nacobbus aberrans. La producción artesanal de hongos biocontroladores se desarrolla sobre sustratos sólidos. Los objetivos del presente trabajo fueron analizar: 1) La producción de conidias de P. lilacinum LPSC # 876 cultivado sobre diferentes sustratos sólidos con varias relaciones C/N, y 2) El efecto de algunos productos fermentados conteniendo conidias de P. lilacinum sobre la población de N. aberrans en plantas de tomate (Lycopersicon esculentum Mill.) cv. Platense cultivadas en maceta en invernáculo. La producción de conidias fue significativamente diferente entre los sustratos utilizados (granos, afrecho y cáscara de arroz, residuo de gírgola, cáscara de langostino y aserrín) siendo mayor sobre afrecho de arroz y en las combinaciones que incluían este sustrato. Los recuentos de conidias más altos (1010 conidias/g de producto fermentado) se correspondieron con una relación C/N entre 16:1 y 29:1. Se encontraron diferencias significativas entre tratamientos en el efecto de P. lilacinum sobre N. aberrans. Las plantas inoculadas con conidias producidas en afrecho de arroz y residuo de gírgola mostraron la menor cantidad de agallas, de masas de huevos y de huevos por masa de huevos. Sin embargo, no se evidenció una actividad antagónica concluyente sobre el nematodo. El afrecho de arroz provee los nutrientes necesarios para una buena producción de conidias de P. lilacinum aunque su combinación con residuo de gírgola mejora la producción. Es necesario rediseñar las estrategias experimentales para demostrar el antagonismo de P. lilacinum hacia N. aberrans.; Purpureocillium lilacinum (Thom) Samson (Luangsa-ard et al.) has been reported for the control of the root-knot disease caused by Nacobbus aberrans. Artisanal production of biocontrol fungal agents is carried out on solid substrates. The objectives of the present work were to analyze: 1) the production of conidia by P. lilacinum LPSC # 876 grown on different solid substrates with various C/N ratios, and 2) the effect of some of the fermented products obtained containing P. lilacinum conidia on tomato plants (Lycopersicon esculentum Mill.) cv. Platense (cultivated in pots under greenhouse conditions) inoculated with N. aberrans. Conidial production varied depending on the substrates utilized (rice grains, bran and husk, oyster mushroom residue, shrimp shell and sawdust); rice bran (alone or in combination with other substrates) yielded the best results. The maximum conidia production (1010 conidia/g of fermented product) corresponded to C/N ratios from 16:1 to 29:1. Significant differences were found on the effect of P. lilacinum onto N. aberrans. Tomato plants inoculated with conidia produced on rice bran mixed with oyster mushroom residue showed the lowest amount of galls, egg masses and eggs per egg masse. Nevertheless, an antagonistic effect on the nematode was not evidenced clearly. Rice bran contains the necessary nutrients for a good conidial production by P. lilacinus although its combination with oyster mushroom residue resulted in higher yields. It is necessary to redesign the experimental strategies to demonstrate the antagonism of P. lilacinus onto N. aberrans.

Bioativadores naturais no desempenho fisiológico de sementes de beterraba

2022-04-28T17:32:59Z

Articulo Natural bioactivators in physiological performance of beet seeds Revista de la Facultad de Agronomía; vol. 115, no. 2 A cultura da beterraba sofre com a desuniformidade na emergência em campo, isso incentiva a busca por alternativas que melhorem o desempenho germinativo e o desenvolvimento inicial de plântulas da beterraba. Objetivou-se determinar o efeito do extrato aquoso de tiririca (Cyperus rotundus L.) e do ácido indol-3-butírico (AIB) sobre a germinação e desenvolvimento inicial de plântulas de beterraba. Foram conduzidos dois experimentos, em ambos foi empregado o delineamento inteiramente casualizado com quatro repetições de 25 sementes por tratamento para germinação e 20 sementes para comprimento da raiz primária. No primeiro experimento, as sementes beterraba foram submetidas às concentrações de 0,0, 0,5, 1,0, 1,5 mgL-1 de AIB. No segundo experimento, as sementes da espécie estudada foram submetidas às concentrações de 0, 15, 25, 50 e 100% do extrato aquoso de tiririca, confrontadas com a melhor concentração obtida da auxina sintética, no primeiro experimento. As avaliações consistiram do teste de germinação, primeira contagem de germinação, índice de velocidade de germinação e comprimento de radícula. Os dados obtidos foram submetidos à análise de variância, com médias comparadas pelo teste de Tukey a 5% de probabilidade e regressão polinomial. Observou-se que não houve diferença significativa entre as concentrações do AIB comparadas à testemunha. O emprego do extrato aquoso de tiririca na concentração de 100%, durante a embebição das sementes de beterraba, favorece o desenvolvimento inicial das plântulas elevando a velocidade de germinação estimulando a protrusão e maior desenvolvimento da raiz principal, quando comparado ao emprego da auxina sintética e às sementes sem qualquer tratamento.; Sugar beet crop suffers from uneven emergence in field which encourages the search for alternative methods to improve germination performance and the initial development of sugar beet seedlings. The objective of this work was to evaluate the effect of aqueous extract of purple nutsedge (Cyperus rotundus L.) and indole-3-butyric acid (IBA) on the germination and early stages of development of sugar beet seedlings. Two experiments were conducted in a completely randomized design with four replications. The germination test was performed with four replications of 25 seeds per treatment and four replications of 20 seeds were used for the primary root length test. In the first experiment, sugar beet seeds were treated with concentrations of 0,0, 0,5, 1,0, 1,5 mgL-1 of IBA. In the second experiment, the seeds were treated with concentrations of 0, 15, 25, 50 and 100% of the aqueous extract of purple nutsedge and with the best concentration obtained from the synthetic auxin selected in the first experiment. The following tests were performed: germination, first count of germination, germination speed index and root length. The data were analyzed using analysis of variance and the averages were compared by Tukey test at 5% probability and polynomial regression was also made. There was no significant difference between the IBA concentrations compared to the control. The use of aqueous extract of purple nutsedge in the concentration of 100% during soaking sugar beet seeds favor the early development of seedlings and increasing the speed of germination stimulating root protrusion and higher main root development when compared to the use of synthetic auxin and to seeds without any treatment.

Adubação nitrogenada em cultivares de batata em diferentes condições edafoclimáticas no estado de Minas Gerais-Brasil

2019-11-13T20:02:25Z

Articulo Nitrogen fertilization in potatoes cultivars at differents soil and climatic conditions in Minas Gerais state Brazil Revista de la Facultad de Agronomía; vol. 115, no. 2 A nutrição adequada na cultura da batata resulta em alta produtividade e qualidade de tubérculos e resistência à doenças e pragas. Dessa forma, objetivou-se avaliar a resposta de doses de fertilizantes nitrogenados no incremento da produtividade de tubérculos das cultivares Ágata e Atlantic em diferentes safras e condições edafoclimáticas. Os experimentos foram conduzidos nas safra da seca, em 2009, nos municípios de Serra do Salitre e São Gotardo com as cultivares Atlantic e Ágata, respectivamente. Em 2010, na safra de inverno, em Itajubá, utilizou-se a cultivar Ágata. O delineamento dos experimentos foi em blocos casualizados com cinco tratamentos que consistiram das doses: 70, 140, 210 e 280 kg ha-1 de nitrogênio e tratamento controle em quatro repetições. A produtividade e classificação dos tubérculos foi baseada na massa fresca e no diâmetro dos tubérculos. A resposta à adubação nitrogenada pela batateira variou em função da região e da época de plantio. As doses crescentes não acarretaram aumento na produtividade, classificação e nos teores de sólidos solúveis dos tubérculos da cultivar Atlantic, em Serra do Salitre, região central do estado de Minas Gerais. A produtividade da cultivar Atlantic em todas as doses foi alta para esta região. Para a cultivar Ágata, no município de São Gotardo, região sul do estado de Minas Gerais, as maiores produtividades foram obtidas na safra da seca com a dose de 275,50 kg ha-1 correspondendo a produção de 44,70 t ha-1 de tubérculos. Em Itajubá, na região sul de Minas Gerais não houve resposta às crescentes doses da adubação nitrogenada.; Proper nutrition in potato crop results in high productivity and quality of tubers and resistance to diseases and pests. The aim of this study was to evaluate the nitrogen fertilizer rates effect on tuber yield of Agata and Atlantic cultivars potatoes, in different soil and weather conditions. The experiments were set up in the dry season in 2009, in Serra do Salitre and São Gotardo cities, the Atlantic and Agata cultivars potatoes were sown, respectively. In 2010, the Agata cultivar potato was sown in Itajubá city. The design of the experiments was randomized blocks with five treatments consisted of: 70, 140, 210 and 280 kg ha-1 of nitrogen rates and treatment control in four replications. Yield and classification were calculated based on fresh matter and diameter of the tubers. The effect to nitrogen fertilization on potato was influenced by the locality and the crop season. There were no differences among the nitrogen rates regard to soluble solids of tubers for Atlantic cultivar potato sown in Serra do Salitre city. The greatest for yield tubers occurred in Serra do Salitre. The greatest average for yield occurred in the dry season at 275,50 kg ha-1 nitrogen rate and achieved a tuber yield of 44.70 t ha-1 to Agata cultivar in São Gotardo. There was no response to increasing doses of nitrogen rates in Itajubá city.

Ocorrência e flutuação populacional de insetos-praga em pomares de macieira da região norte do Paraná

2019-11-13T20:02:33Z

Articulo Occurrence and population fluctuation of insects-pest in apple orchards in North Paraná Revista de la Facultad de Agronomía; vol. 115, no. 2 O presente estudo teve o objetivo de identificar as principais espécies de insetos presentes em pomares da região Norte do Paraná e acompanhar a flutuação das populações. O estudo foi realizado em quatro pomares de macieira cv. ‘Eva’, nos municípios de Cambé, Londrina, São Sebastião da Amoreira e Uraí. Utilizou-se armadilhas delta com feromônio sexual para Grapholita molesta e Bonagota salubricola; Jackson com feromônio de Ceratitis capitata; e McPhail com proteína hidrolisada a 5% e suco de uva a 25% para moscas-das-frutas e mariposas. G. molesta foi a espécie mais frequente com ocorrência durante todo o período estudado. B. salubricola não foi capturada em nenhuma as áreas avaliadas. A espécie de mosca-das-frutas predominante foi C. capitata, enquanto que Anastrepha fraterculus esteve presente em número reduzido. Foram identificadas 12 espécies de mariposas consideradas “grandes lagartas”, sendo Chabuata major (Noctuidae) a mais abundante.; This study aimed to identify the main species pest present in apple orchards in north Paraná and their population fluctuation. The monitoring was carried out weekly in four apple orchards cv. ‘Eva’, in the cities of Cambé, Londrina, São Sebastião da Amoreira and Uraí. We used traps delta with pheromone for Grapholita molesta, Bonagota salubricola and Ceratitis capitata, and McPhail traps with hydrolyzed protein or grape juice to fruit fly and moths. G. molesta was captured in large numbers during the collection period, whereas B. salubricola was not captured in any the collection areas. The predominant fruit fly species was C. capitata, while Anastrepha fraterculus was present in small numbers. Twelve moth species were identified, being Chabuata major (Noctuidae) the most abundant.

Influência de doses reduzidas e épocas de aplicação sobre o efeito hormético de glyphosate em feijoeiro

2019-11-13T20:02:32Z

Articulo Influence of low doses and application times on the hormesis effect of glyphosate in common bean Revista de la Facultad de Agronomía; vol. 115, no. 2 Com o objetivo de avaliar se os resultados do efeito hormético de glyphosate em feijoeiro são influenciados pela dose empregada e o estádio fenológico da cultura no momento da aplicação, foi conduzido um estudo no município de Selvíria, Mato Grosso do Sul, Brasil, utilizando-se o herbicida glyphosate (Roundup Original®) aplicado em baixas doses (zero, 3, 6, 9, 12 e 15 g ha-1 do equivalente ácido) e em diferentes estádios fenológicos do feijoeiro (V4-4; V4-7; ½ V4-4 + ½ V4-7). O delineamento experimental utilizado foi em blocos casualizados com 18 tratamentos dispostos em esquema fatorial 6 x 3, com quatro repetições. De maneira geral, a aplicação de subdoses de glyphosate inferiores a 15 g ha-1 proporcionou redução da massa vegetativa do feijoeiro e incrementos na produtividade de até 375 kg ha-1 quando feita a aplicação de 12 g ha-1 em dois estádios fenológicos, ou seja, 6 g ha-1 em V4-4 e 6 g ha-1 em V4-7. Portanto, neste estudo foi possível verificar a influência da época de aplicação do herbicida glyphosate sobre o efeito hormético e confirmar a hipótese de hormese gerando aumentos de produtividade na cultura do feijão.; With the aim of assessing whether the results of hormetic effect of glyphosate on common bean plants are influenced by the dose used and the phenological stage of the crop at the time of application, a study was conducted in Selvíria, Mato Grosso do Sul, Brazil, using glyphosate (Roundup Original®) applied at low doses (zero, 3, 6, 9, 12 and 15 g ha-1 acid equivalent) and at different growth stages of common bean (V4-4; V4-7; ½ V4-4 + ½ V4-7). The experimental design was randomized blocks with 18 treatments in a factorial 6 x 3, with four replications. In general, the use of lower doses of glyphosate at 15 g ha-1 gave a reduction of vegetative mass and an increase in common bean yield in the order of up to 375 kg ha-1 when done applying 12 g ha-1 in two phenological stages, or 6 g ha-1 in V4-4 and 6 g ha-1 in V4-7. Therefore, in this study it was possible to verify the influence of glyphosate herbicide application timing to guarantee the hormesis effect and confirm the hormesis hypothesis generating increases in productivity in common bean crop.

Rendimiento y extracción de nutrientes en estaqueros de álamo del Delta del Paraná fertilizados con nitrógeno o fósforo

2019-11-13T20:02:27Z

Articulo Yield and nutrient extraction from poplar nurseries fertilized with nitrogen or phosphorus Revista de la Facultad de Agronomía; vol. 115, no. 2 Los estaqueros de Salicáceas producen material de propagación para plantaciones clonales. Con la cosecha anual de guías se exportan nutrientes del sistema y, en ciclos sucesivos de producción, pueden reducirse la fertilidad del suelo y la productividad de las cepas. La fertilización posibilita compensar la extracción de nutrientes y aumentar los rendimientos. Sin embargo, si la fertilización no produce mayor crecimiento y sólo aumenta la acumulación de nutrientes en los tallos, la extracción de nutrientes con la cosecha aumentará innecesariamente. En este trabajo se evaluó cómo es afectado el rendimiento y la extracción de nutrientes en estaqueros comerciales de Populus deltoides (clones `Australiano 129/60´ y “150-82”) fertilizados con N o P. El ensayo incluyó tres tratamientos: fertilización con N, con P y control sin fertilizar. La fertilización con P no aumentó el rendimiento en ningún clon. Sin embargo, hubo diferencias entre los clones en respuesta a la fertilización con N. La concentración de N foliar, el contenido de N en hojas y tallos, el rendimiento y la extracción de N en la cosecha aumentaron en el clon “150-82” en comparación con plantas no fertilizadas. La fertilización con N no aumentó el rendimiento del clon `Australiano 129/60´ ni la extracción de nutrientes. La densidad básica de la madera fue inferior en plantas fertilizadas con N en ambos clones, con respecto a plantas no fertilizadas. Concluimos que no es necesario fertilizar los estaqueros del clon `Australiano 129/60´, mientras que los del clon “150-82” podrían ser fertilizados con N para aumentar su rendimiento.; Salicaceae stool beds produce propagating material for clonal plantations. With the annual shoot harvest, nutrients are exported from the system and in consequence, in successive production cycles, soil fertility can be reduced and thus decrease productivity of plants. Fertilization enables to compensate for nutrient extraction and increase yields. However, if fertilization does not increase growth but only increases nutrient accumulation in the stems, nutrient extraction with the harvest would increase unnecessarily. In this study was evaluated how yield and nutrient extraction are affected in commercial stool beds of Populus deltoides clones -`Australiano 129/60´ and “150-82”- when fertilized with N or P. The assay included three treatments: fertilization with N (50 g of urea per plant), fertilization with P (100 g of triple superphosphate per plant) and unfertilized control plants. P fertilization did not increase yield of neither of the clones. However, there were differences among clones in the response to N fertilization. Foliar concentration of N, leaf and stem N content, yield and extraction of N at harvest, increased in clone “150-82” compared with unfertilized plants. In clone 'Australiano 129/60' fertilization with N did not increase yield or nutrient extraction with the harvest. The basic wood density was lower in plants fertilized with N in both clones, compared to unfertilized plants. We conclude that it is not necessary to fertilize stool beds of 'Australiano 129/60', and that “150-82” stool beds could be fertilized with N to increase its yield.

Producción potencial de semillas por planta en especies de Bromus (Sección Ceratochloa), en el sudeste de la provincia de Buenos Aires

2024-12-02T18:54:11Z

Articulo Potential seed production per plant in species of Bromus (Section Ceratochloa) at southeast of Buenos Aires province Revista de la Facultad de Agronomía; vol. 115, no. 2 En Argentina crecen varias especies de la Sección Ceratochloa del género Bromus, que se destacan por su producción de forraje inverno-primaveral. El valor de estos recursos nativos ha incentivado la colecta de semillas de diferentes poblaciones las que se conservan en Bancos de Germoplasma para su eventual utilización en la obtención de variedades de alta producción de forraje y/o semilla, previa evaluación de sus características. Con el objetivo de determinar la producción potencial de semillas por planta mediante los componentes de rendimiento, se cultivaron en Balcarce 10 poblaciones pertenecientes a B. bonariensis, B. coloratus, B. parodii y B. catharticus (variedades: catharticus, rupestris y elata), y dos cultivares (Gato y Volcán), según un diseño en bloques completos con n=4 y 12 plantas/parcela. Se registraron el número de panojas/planta, de espiguillas/panoja y de flores/espiguilla, y se estimó el número potencial de semillas por panoja y planta, peso de 1000 semillas y rendimiento (g/panoja y g/planta). Se realizó análisis de la varianza y comparación de tratamientos con DMS (p<0,05). Los materiales genéticos no difirieron en el número de semillas/panoja ante la compensación establecida entre los componentes de esa variable, pero sí a nivel planta, debido principalmente a la cantidad diferencial de panojas/planta. Hubo compensación entre peso y número de semillas, pero igualmente los materiales presentaron diferencias en rendimiento (g) Éste fue mayor en los cultivares y en dos poblaciones silvestres pertenecientes a B. bonariensis y a B. catharticus var. catharticus, las que constituyen materiales promisorios para su inclusión en planes de mejoramiento.; Several species of the genus Bromus, Section Ceratochloa, grow in Argentina. They have an exceptional winterspring forage production. The value of these native resources has encouraged the collection of seeds from different populations. After assessing their characteristics, these seeds are conserved in germplasm banks for their eventual use to obtain high-yield forage and/or seed varieties. The objective of this study was to determine the potential seed production per plant based on the evaluation of yield components. Ten populations of B. bonariensis, B. coloratus, B. parodii, and B. catharticus (varieties: catharticus, elata, and rupestris), and two cultivars (Gato and Volcan) were grown in Balcarce, applying a randomized complete block design with n = 4 and 12 plants/plot. The number of panicles/plant, spikelets/panicle, and flowers/spikelet were recorded, and the potential number of seeds per panicle and per plant, the weight of 1000 seeds, and the potential yield were estimated. The data were analyzed using ANOVA followed by an LSD test (p<0,05). Genetic materials did not differ in number of seeds/panicle due to the established compensation between the components of that variable. However, there were differences at the plant level, mainly due to the differential amount of panicles/plant. Despite the compensation between weight and number of seeds, the materials presented differences regarding the potential yield of seed/plant (g). The yield was higher for the cultivars and two wild populations belonging to B. bonariensis and B. catharticus var. catharticus, which constitute promising materials to be included in plant breeding programs.

Tabela de vida de fertilidade da joaninha asiática em diferentes temperaturas

2019-11-13T20:02:26Z

Articulo Fertility life table of the Asian ladybug in different temperatures Revista de la Facultad de Agronomía; vol. 115, no. 2 A joaninha Harmonia axyridis (Pallas), encontra-se distribuída em vários países sendo considerada um dos principais predadores de afídeos. Com o objetivo de avaliar a influência de diferentes temperaturas na dinâmica populacional de H. axyridis foram elaboradas tabelas de vida de fertilidade. Em laboratório, os experimentos foram conduzidos em câmaras climatizadas reguladas a 18; 21; 24; 27 e 30oC. Larvas da espécie foram separadas e mantidas em placas de vidro alimentadas com ovos de Anagasta kuehniella (Zeller). Os adultos da joaninha foram separados em 20 casais e mantidos em copos plásticos recebendo o mesmo tipo de alimento da fase larval. Os parâmetros de tabela de vida de fertilidade estimados evidenciam que sob temperatura de 18 e 21oC H. axyridis apresenta maior taxa de crescimento (rm); quando mantida sob 27oC ocorre incremento da taxa de fertilidade (Ro), produzindo maior número de descendentes. O aumento populacional (λ) de H. axyridis variou de 1,27 a 1,80 quando submetida a diferentes temperaturas.; The Asian ladybug, Harmonia axyridis (Pallas), is distributed in several countries and is considered as one of the main aphid predators. Life tables were prepared to evaluate the influence of different temperatures on the population dynamics of H. axyridis. Laboratory experiments were conducted in climate chambers regulated at 18, 21, 24, 27, and 30°C. Larvae of the species were separated, maintained on glass plates, and fed Anagasta kuehniella (Zeller) eggs. Adults were separated, and 20 couples were maintained in plastic cups; they received the same type of food at the larval stage. Fertility life table parameters show that H. axyridis exhibits a higher growth rate at a temperature of 18 to 21°C. An increase in the fertility rate was observed when H. axyridis was maintained under 27°C, producing the largest number of descendants. The population increase in H. axyridis ranged from 1.27 to 1.80 when subjected to different temperatures.

Análise econômica da produção do milho doce cultivado com aplicação de bioestimulante via semente

2022-04-28T17:45:00Z

Articulo Agroeconomic analysis of sweet corn grown with biostimulant applied on seed Revista de la Facultad de Agronomía; vol. 115, no. 2 O objetivo deste trabalho foi estimar e avaliar as variações nos custos totais do milho doce tratado via semente com diferentes doses de bioestimulante. O experimento foi instalado na área experimental da Universidade Federal de Mato Grosso do Sul, campus de Chapadão do Sul, em Latossolo Vermelho Distrófico argiloso. O delineamento experimental utilizado foi de blocos casualizados com quatro repetições, totalizando 32 parcelas. Os tratamentos foram compostos por oito doses de bioestimulante Stimulate®: 0,0; 4,0; 8,0; 12,0; 16,0; 20,0; 24,0 e 28,0 mL kg-1 de sementes. A parcela foi composta por cinco linhas de cinco metros de comprimento, espaçadas em 0,45 m entre linhas, sendo consideradas como área útil as três linhas centrais da parcela. Foi estimado o custo operacional total, custo operacional efetivo, receita bruta, margem bruta, ponto de nivelamento, preço de equilíbrio, lucro operacional e índice de lucratividade. A utilização do bioestimulante acarretou na melhoria de todas as variáveis analisadas neste trabalho, em relação ao tratamento controle em que não houve a aplicação do produto. Concluiu-se que as despesas com os insumos constituem o item que mais onerou os custos de produção, destacando a aquisição e o tratamento das sementes, além das despesas com operações manuais. Para maior lucratividade, recomenda-se a utilização do bioestimulante na dose 16,0 mL kg-1 de sementes de milho doce.; The aim of this study was to estimate and evaluate the variations in the total costs of a sweet corn crop treated via seed with different doses of biostimulant. The experiment was installed in the experimental area of the Federal University of Mato Grosso do Sul, campus of Chapadão do Sul in Oxisoil clay. The experimental design was a randomized block with four replications, totalizing 32 plots. The treatments consisted of eight biostimulant Stimulate® doses: 0.0; 4.0; 8.0; 12.0; 16.0; 20.0; 24.0 and 28.0 ml kg-1 of seed. The plot consisted of five rows of five meters in length, spaced 0.45 m between rows, considering useful area the tree central lines of the plot. Was estimated total operating cost, effective operational cost, gross revenue, gross margin, leveling point, equilibrium price, operating income and profitability index. The use of biostimulant resulted in the improvement of all the variables analyzed in this study, compared to the control treatment where no product application. Was concluded that the cost of the inputs are the item that most burdened production costs, highlighting the seed acquisition and seed treatment, in addition to the costs of manual operations. For greater profitability, is recommended the use of biostimulant dose of 16.0 mL kg-1 sweet corn seeds.