Aplicação de biofertilizante, composto e uréia na produção de capim tanzânia (Panicum maximum, Jacq.) sob irrigação

Pós-graduação em Zootecnia - FCAV

Atributos químicos e físicos de um argissolo cultivado com Panicum maximum Jacq. cv. IPR-86 Milênio, sob lotação rotacionada e adubado com nitrogênio

A avaliação dos atributos químicos e físicos do solo é necessária em estudos que exploram intensivamente os sistemas de pastejo. No presente trabalho, objetivou-se avaliar as variações nos atributos físicos e químicos de um Argissolo cultivado com capim-milênio, sob pastejo, no intervalo compreendido entre outubro/2001 e maio/2002, no quinto ano de aplicação sucessiva das seguintes doses de N: 0, 150, 300 e 450 kg ha-1. Após os cinco anos de aplicação de 450 kg ha-1 de N, o teor de MO aumentou em 5 g dm-3, o que resultou em aumento da CTC. No período de outubro/2001 a maio/2002 houve diminuição nos valores de pH e de V com a aplicação de N. A densidade do solo variou pouco com a adubação nitrogenada; a percentagem de microporos aumentou e a de macroporos diminuiu na camada de 0-5 cm com o aumento das doses de N, mas a porosidade total permaneceu constante; e a resistência à penetração, quando o solo apresentava 90 g kg-1 de água, não foi afetada pelas doses de N e não foi restritiva ao crescimento das plantas.

Predicting Growth of Panicum maximum: An Adaptation of the CROPGRO-Perennial Forage Model

Warm-season grasses are economically important for cattle production in tropical regions and tools to aid in management and research on these forages would be highly beneficial both in research and the industry. This research was conducted to adapt the CROPGRO-Perennial Forage model to simulate growth of the tropical species guineagrass (Panicum maximum Jacq. cv. 'Tanzania') and to describe model adaptation for this species. To develop the CROPGRO parameters for this species, we began with values and relationships reported in the literature. Some parameters and relationships were calibrated by comparison with observed growth, development, dry matter accumulation, and partitioning during a 17-mo experiment with Tanzania guineagrass in Piracicaba, SP, Brazil. Compared with starting parameters for palisadegrass [Brachiaria brizantha (A. Rich.) Stapf. cv. 'Xaraes'], dormancy effects of the perennial forage model had to be minimized, partitioning to storage tissue or root decreased, and partitioning to leaf and stem increased to provide for more leaf and stem growth and less root. Parameters affecting specific leaf area and senescence of plant tissues were improved. After these changes were made to the model, biomass accumulation was better simulated, mean predicted herbage yield was 6576 kg ha(-1), averaged across 11 regrowth cycles of 35 (summer) or 63 d (winter), with a RMSE of 494 kg ha(-1) (Willmott's index of agreement d = 0.985, simulated/observed ratio = 1.014). The model also gave good predictions against an independent data set, with similar RMSE, ratio, and d. The results of the adaptation suggest that the CROPGRO model is an efficient tool to integrate physiological aspects of guineagrass and can be used to simulate growth.

Planting and production of switchgrass (Panicum virgatum L.) as a bioenergy crop in Michigan's Upper Peninsula

Switchgrass (Panicum virgatum L.) is a perennial grass holding great promise as a biofuel resource. While Michigan’s Upper Peninsula has an appropriate land base and climatic conditions, there is little research exploring the possibilities of switchgrass production. The overall objectives of this research were to investigate switchgrass establishment in the northern edge of its distribution through: investigating the effects of competition on the germination and establishment of switchgrass through the developmental and competitive characteristics of Cave-in-Rock switchgrass and large crabgrass (Digitaria sanguinalis L.) in Michigan’s Upper Peninsula; and, determining the optimum planting depths and timing for switchgrass in Michigan’s Upper Peninsula. For the competition study, a randomized complete block design was installed June 2009 at two locations in Michigan’s Upper Peninsula. Four treatments (0, 1, 4, and 8 plants/m2) of crabgrass were planted with one switchgrass plant. There was a significant difference between switchgrass biomass produced in year one, as a function of crabgrass weed pressure. There was no significant difference between the switchgrass biomass produced in year two versus previous crabgrass weed pressure. There is a significant difference between switchgrass biomass produced in year one and two. For the depth and timing study, a completely randomized design was installed at two locations in Michigan’s Upper Peninsula on seven planting dates (three fall 2009, and four spring 2010); 25 seeds were planted 2 cm apart along 0.5 m rows at depths of: 0.6 cm, 1.3 cm, and 1.9 cm. Emergence and biomass yields were compared by planting date, and depths. A greenhouse seeding experiment was established using the same planting depths and parameters as the field study. The number of seedlings was tallied daily for 30 days. There was a significant difference in survivorship between the fall and spring planting dates, with the spring being more successful. Of the four spring planting dates, there was a significant difference between May and June in emergence and biomass yield. June planting dates had the most percent emergence and total survivorship. There is no significant difference between planting switchgrass at depths of 0.6 cm, 1.3 cm, and 1.9 cm. In conclusion, switchgrass showed no signs of a legacy effect of competition from year one, on biomass production. Overall, an antagonistic effect on switchgrass biomass yield during the establishment period has been observed as a result of increasing competing weed pressure. When planting switchgrass in Michigan’s Upper Peninsula, it should be done in the spring, within the first two weeks of June, at any depth ranging from 0.6 cm to 1.9 cm.

Einzelheiten höherer Pflanzen : 23. Panicum turgidum: Blattquerschnitt, Gras - 24. Orthostemon sellowianus: Knospe im Längenschnitt - 25. Orthostemon sellowianus: Fruchtknotenquerschnitt - 26. Conium maculatum: Frucht, Schierling - 27. Conium maculatum: F

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Dune stabilization with Panicum amarum along the North Carolina coast /

"February 1976."

Evaluación del riesgo de introducción de plaga en semilla de pastos Brachiaria brizantha A. Rich y Panicum maximun Jacq de origen Brasil, Nicaragua 2014.

Nicaragua importa semilla de pasto con el objetivo de resolver la baja productividad y calidad del pasto. Las especies Brachiaria brizantha y Panicum maximun, son las semilla de pasto de mayor importación en nuestro país, siendo Brasil el país de donde más importamos. Basados en que existen algunas plagas en Brasil que no existen en Nicaragua, se procedió a realizar un análisis de riesgo de plaga, el cual es una herramienta que permite evaluar la entrada, establecimiento, dispersión y manejo del riesgo de la plaga. Las etapas del análisis de riesgo de plaga; se realizó con la recopilación y análisis de información clave de fuente primaria y secundaria como son la lista de plagas asociadas al cultivo de pasto de Brasil, lista oficial de plagas asociadas al cultivo pasto en Nicaragua, diagnóstico fitosanitario en plantaciones de pasto B. brizantha en Nicaragua y los resultados de laboratorio de las semilla de pasto de origen Brasil que ingresaron por el país en el 2014. Este estudio se realizó en un período de 12 meses de Enero a Diciembre del 2014, en la Región Autónoma del Caribe Sur (RACS), en el municipio de El Rama y dos departamentos Chontales y Rio San Juan en los municipios de La Gateada y San Miguelito respectivamente, ya que son representativos, son las zonas de mayor producción de pasto, y en los doce puesto de cuarentena agropecuaria del territorio nacional, El Guasaule, Puerto Corinto, Aduana Central Aérea, Las Manos, El Espino, Peñas Blancas, Teotecacinte, Aeropuerto Internacional Augusto César Sandino, El Rama, El Bluff, San Carlos y San Juan de Nicaragua, que es donde ingresan las importaciones de semilla de pasto de origen Brasil. El muestreo fue al azar, tanto para el diagnóstico fitosanitario como para las importaciones de semilla de pasto de origen Brasil, tomando muestras para ser analizadas en los laboratorios de herbología, entomología, micología, bacteriología y nematología. El diagnóstico fitosanitario, permitió corroborar la presencia de plagas mencionadas en la lista oficial de plagas asociadas al cultivo pasto en Nicaragua y descartar presencias de plagas cuarentenarias en los pasto de nuestro país. En las semilla de pasto importadas de Brasil, se determino la presencia de plagas de interés cuarentenario como son la maleza Commelina benghalensis y nemátodo de punta blanca Aphelenchoides besseyi. En el análisis de riesgo de plaga, se identificaron siete plagas de interés cuarentenario para la especie B. brizantha y noventa y uno plagas para la especie P. maximun, al evaluar cada plaga por la posibilidad de seguir la vía de entrada, se determinaron dos plagas de importancia cuarentenarias para el área del análisis de riesgo de plagas, como son la maleza Commelina benghalensis L. y nemátodo de punta blanca Aphelenchoides besseyi Ch., ya que son plagas consideradas de alto riesgo fitosanitario debido a la posibilidades de sobrevivir, multiplicarse y diseminarse en el ambiente de Nicaragua una vez introducida en nuevas aéreas establecidas, de acuerdo a la evaluación del riesgo de establecimiento y dispersión; es por eso que en ambas plagas se determinaron las opciones del manejo del riesgo para disminuir a niveles adecuados los riesgo de dichas plagas para nuestro país.

Avaliação da produção e da qualidade do capim Panicum maximum cv. Massai

Dissertação (mestrado)—Universidade de Brasília, Faculdade de Agronomia e Medicina Veterinária, 2016.

Evaluación de diferentes dosis de thiamethoxan en el establecimiento de praderas de panicum maximun cv mombasa

Tesis (Zootecnista). -- Universidad de La Salle. Facultad de Ciencias Agropecuarias. Programa de Zootecnia, 2014

INFLUENCE OF A NATIVE INSECTARY PLANT, CHAMAECRISTA FASCICULATA (MICHX.) ON ORGANIC FIELD CORN AND ARTHROPOD COMMUNITIES

Increasing plant diversity in conventionally monoculture agrosystems has been promoted as a method to enhance beneficial arthropod density and efficacy, suppress herbivory and provide a range of ecosystem services. I investigated the pest suppressive potential and economic impact of plant diversification in organic field corn. The experiment consisted of two treatments, corn grown in monoculture (C) and bordered by strips of partridge pea (PP). Pest and natural enemy populations, corn damage, yield, and profits were compared among treatments. Natural enemy and herbivore arthropod populations were affected by treatment and distance from plot border. Corn damage due to pests was also affected by treatment and location, but did not significantly affect yield. Yield in monoculture plots was generally greater than in PP but did not result in greater profit. Pest and natural enemy arthropod abundances were elevated in partridge pea treatment borders, but these populations did not consistently diffuse into plot interiors. The potential causes and implications of findings are discussed.

Dinâmica populacional de Scaptocoris carvalhoi (becker, 1967) em Panicum maximum cv. Mombaça na região de ecótono do cerrado-pantanal sul-mato-grossense

2015

Avaliação visual e seleção de plantas com retenção de sementes entre cruzamentos em Panicum maximum

2015