Cassava yield in conventional and no-tillage cultivation in integrated crop-livestock systems

O objetivo deste trabalho foi avaliar a produtividade de mandioca (Manihot esculenta), bem como a densidade e o teor de carbono do solo, sob cultivo em plantio direto e convencional, em rotação com capim-marandu (Urochloa brizantha) submetido a pastejo. Os tratamentos consistiram de mandioca cultivada como a seguir: em plantio convencional após dois (CC-2P) e quatro (CC-4P) anos de pastagem; em plantio direto após dois (NTC-2P) e quatro (NTC-4P) anos de pastagem; e com pastagem perene (PP) de capim-marandu. O tratamento CC-2P apresentou maior produtividade de mandioca no ano-safra de 2016/2017 (63,29 Mg ha-1) do que o NTC-2P (47,85 Mg ha-1). No ano-safra de 2018/2019, não foram observadas diferenças significativas quanto à produtividade entre CC-4P (60,95 Mg ha-1 e NTC-4P (60,68 Mg ha-1). Entre 2012 e 2019, o teor de carbono no solo (0–10 cm) diminuiu no tratamento CC-2P. Em 2019, o estoque de carbono foi maior para o NTC-4P, em comparação aos de CC-4P e CC-2P, tendo aumentado de 16,41 Mg ha-1 a 21,46 Mg ha-1. A produtividade da mandioca varia conforme o ano-safra, enquanto o teor de carbono no solo diminui após o tratamento CC-2P, mas aumenta após o NTC-4P.The objective of this work was to evaluate cassava (Manihot esculenta) crop yield, as well as soil density and carbon content, under no‑tillage and conventional cultivation, in rotation with palisade grass (Urochloa brizantha) subjected to grazing. Treatments consisted of cassava cultivated as follows: in conventional tillage after 2 (CC-2P) and 4 (CC-4P) years of pasture; in no-tillage after 2 (NTC-2P) and 4 (NTC-4P) years of pasture; and with perennial pasture (PP) of palisade grass. The CC-2P treatment showed higher cassava yield in the 2016/2017 crop year (63.29 Mg ha-1) than NTC-2P (47.85Mg ha-1). However, in the 2018/2019 crop year, no significant yield differences were observed between CC-4P (60.95 Mg ha-1) and NTC-4P (60.68 Mg ha-1). Between 2012 and 2019, soil carbon content (0–10 cm) decreased in the CC-2P treatment. In 2019, carbon stock was higher for NTC-4P compared with CC-4P and CC-2P, increasing from 16.41 to 21.46 Mg ha-1 between 2012 and 2019. Cassava yield varies depending on crop year, whereas soil carbon content decreases after CC-2P, but increases after NTC-4P

Forage production and morphological components of coastcross pasture mixed with peanut forage

Objetivou-se avaliar a produção de forragem e a composição morfológica de uma pastagem de coastcross (Cynodon dactylon, cv. Coastcross) consorciada com amendoim forrageiro (Arachis pintoi, cv. Amarillo) com e sem adubação nitrogenada e submetida a pastejo com lotação continua. Utilizou-se um delineamento experimental em blocos ao acaso com parcelas subdivididas no tempo, com duas repetições, para avaliação das seguintes combinações: coastcross + amendoim forrageiro + 200 kg/ha de N; coastcross + amendoim forrageiro + 100 kg/ha de N; coastcross + 200 kg/ha de N e coastcross + amendoim forrageiro. Para estimar a disponibilidade de massa de forragem e a produção de forragem, foram usadas as técnicas da dupla amostragem e do triplo emparelhamento, respectivamente, a cada 28 dias. Foram avaliadas as proporções de gramínea, leguminosas, invasoras, solo descoberto e liteira. O material da dupla amostragem foi separado em lâmina foliar, bainha+colmo e material morto. A massa de forragem foi menor na pastagem sem adubação com nitrogênio e maior na pastagem adubada com nitrogênio (200 kg/ha) sem amendoim forrageiro. A pastagem sem adubação foi a que apresentou a maior massa de amendoim forrageiro. A produção de forragem foi maior nas pastagens adubadas com nitrogênio na dose de 200 kg/ha, seguidas da pastagem adubada com 100 kg de N/ha. A taxa de acúmulo de forragem seguiu a mesma tendência da produção de forragem. Não foram observadas diferenças para solo descoberto, liteira e área descoberta entre as combinações avaliadas, porém na pastagem adubada com nitrogênio na dose de 200 kg/ha sem leguminosa, houve menor incidência de plantas invasoras. A razão folha/colmo, massa de folhas e massa de material morto não diferiu entre as pastagens, porém aquela adubada com 200 kg de N/ha sem leguminosa apresentou maior massa de colmos.This experiment was carried out from July 2006 to June 2007. It was used an experimental design of random blocks with split plot in time, with two replications using the following treatments: Coastcross + peanut forage + 200 kg/ha of N; Coastcross + Peanut Forage + 100 kg/ha of N; Coastcross + 200 kg/ha of N and Coastcross + Peanut Forage in the following seasons: winter, spring, summer and autumn. To estimate the forage mass production availability, the double sampling and triple pairing technique, respectively, every 28 days was used. The proportions of grass, legumes, weeds, uncovered soil and litter were evaluated. The material from the double sampling technique was separated into leaf blade, stem + sheath and dead material fractions. Regarding of forage availability, the pasture submitted to treatment without nitrogen had the lower mass, while that submitted to 200 kg/ha of nutrient without the presence of legume had the highest forage mass. For the peanut forage mass, the pasture without fertilization presented the best result. The forage production was higher in pastures submitted to treatment with 200 kg of N/ha followed by that fertilized with 100 kg of N/ha. The grass accumulation rate followed the same trend of forage production. No difference were observed for uncovered soil, litter and uncovered area between treatments; however, the pasture submitted to the dose of 200 kg of N/ha without legume presented lower incidence of invasive plants. No differences were observed for the leaf/stem ratio, leaves mass and dead material mass between treatments; however, the grass submitted to 200 kg of N/ha without legume presented the greatest stems mass

Desempenho de bovinos de corte em sistemas integrados de produção agropecuária com capim-marandu e mandioca

An experimental test was carried out to evaluate the stocking rate in animal units per hectare (AU ha-1), average daily gain (ADG) and weight gain per area of beef cattle, in the summer and winter periods, in the following treatments: perennial marandu grass pasture; SIPA - cassava in conventional cultivation or no-tillage, followed by two years of pasture; and cassava in conventional cultivation or no-tillage, followed by four years of pasture. A randomized block design with 4 replications and 4 test animals per treatment was used. Over the seven seasons evaluated, the average stocking rate obtained in the summer period did not differ between the perennial pasture and SIPA areas (8.16 vs. 7.63 AU ha-1) (P>0.05), but in winter it was significantly higher on perennial pasture (3.00 vs. 2.37 AU ha-1) (P<0.05). The ADG of animals on perennial marandu grass pasture was 0.624 kg in summer and 0.387 kg in winter. In SIPA, gains were 0.561 and 0.390 kg in summer and winter, respectively. In perennial pasture, body weight gain (BWG) per area was 1,156 kg ha-1 in summer and 170 kg ha-1 in winter. In SIPA, the GPC was 911 and 122 kg ha-1, respectively, in summer and winter. These gains allowed a significantly higher production of carcass arrobas on perennial pasture compared to SIPA (38.50 vs. 30.40 @ ha-1) (P<0.01) in the summer period. In winter this production did not differ between SIPA and perennial pasture (5.68 vs. 4.46 @ ha-1) (P>0.05). The SIPA with cassava are viable alternatives for the production of beef cattle, allowing animal performance similar to the system with perennial marandu grass pasture.Se realizó un ensayo experimental para evaluar la carga animal en unidades animales por hectárea (UA ha-1), ganancia media diaria (GMD) y ganancia de peso por área de ganado vacuno de carne, en los periodos de verano e invierno, en los siguientes tratamientos: pastizal de pasto marandú perenne; SIPA - yuca en cultivo convencional o sin labranza, seguida de dos años de pastoreo; y yuca en cultivo convencional o sin labranza, seguida de cuatro años de pastoreo. Se utilizó un diseño de bloques al azar con 4 repeticiones y 4 animales de prueba por tratamiento. En las siete temporadas evaluadas, la carga animal promedio obtenida en el período de verano no difirió entre las áreas de pasto perenne y SIPA (8.16 vs. 7.63 AU ha-1) (P>0.05), pero en invierno fue significativamente mayor en las áreas de pasto perenne. pasto (3.00 vs. 2.37 AU ha-1) (P<0.05). La GMD de los animales en pasto marandú perenne fue de 0,624 kg en verano y de 0,387 kg en invierno. En SIPA, las ganancias fueron de 0,561 y 0,390 kg en verano e invierno, respectivamente. En pasto perenne, la ganancia de peso corporal (BWG) por área fue de 1,156 kg ha-1 en verano y 170 kg ha-1 en invierno. En el SIPA, la GPC fue de 911 y 122 kg ha-1, respectivamente, en verano e invierno. Estas ganancias permitieron una producción significativamente mayor de arrobas en canal en pasto perenne en comparación con SIPA (38.50 vs. 30.40 @ ha-1) (P<0.01) en el período de verano. En invierno esta producción no difirió entre SIPA y pasto perenne (5.68 vs 4.46 @ ha-1) (P>0.05). Los SIPA con yuca son alternativas viables para la producción de ganado vacuno de carne, permitiendo un comportamiento animal similar al sistema con pasto marandú perenne.Foi realizado ensaio experimental para avaliação da taxa de lotação em unidades animais por hectare (UA ha-1), ganho médio diário (GMD) e o ganho de peso por área de bovinos de corte, nos períodos de verão e inverno, nos seguintes tratamentos: pasto perene de capim-marandu; SIPA - mandioca em cultivo convencional ou plantio direto, seguida de dois anos de pasto; e mandioca em cultivo convencional ou plantio direto, seguida de quatro anos de pasto. Utilizou-se delineamento em blocos casualizados, com 4 repetições, e 4 animais testadores por tratamento. Ao longo das sete safras avaliadas, a taxa de lotação média obtida no período de verão não diferiu entre as áreas de pasto perene e SIPA (8,16 vs. 7,63 UA ha-1) (P>0,05), mas no inverno ela foi significativamente maior no pasto perene (3,00 vs. 2,37 UA ha-1) (P<0,05). O GMD dos animais no pasto perene de capim-marandu foi de 0,624 kg no verão e 0,387 kg no inverno. Já no SIPA os ganhos foram de 0,561 e 0,390 kg no verão e inverno, respectivamente. No pasto perene o ganho de peso corporal (GPC) por área foi de 1.156 kg ha-1 no verão, e de 170 kg ha-1 no inverno. No SIPA o GPC foi de 911 e 122 kg ha-1, respectivamente, no verão e no inverno. Estes ganhos permitiram uma produção de arrobas de carcaça significativamente superior no pasto perene em relação ao SIPA (38,50 vs. 30,40 @ ha-1) (P<0,01) no período de verão. No inverno esta produção não diferiu entre o SIPA e o pasto perene (5,68 vs. 4,46 @ ha-1) (P>0,05). Os SIPA com mandioca são alternativas viáveis para a produção de bovinos de corte, permitindo desempenho animal semelhante ao sistema com pasto perene de capim-marandu

Soil physical quality in a fertilized pasture under continuous grazing

O objetivo deste trabalho foi avaliar a qualidade física do solo em pastagens submetidas ao pastejo contínuo. As pastagens foram formadas com capim-coastcross (Cynodon dactylon) consorciado ou não com a leguminosa amendoim forrageiro (Arachis pintoi). A pastagem consorciada recebeu os tratamentos de 0, 100 e 200 kg ha-1 de nitrogênio (N) por ano e a pastagem sem consórcio recebeu 200 kg ha-1 de N por ano, no total de quatro tratamentos. O experimento foi implantado em 2002, em Latossolo Vermelho distrófico, em Paranavaí, PR, em delineamento de blocos ao acaso, com duas repetições. A taxa de lotação animal foi controlada em função da oferta de forragem, entre 2002 e 2007. Em março e novembro de 2007 foram coletadas amostras indeformadas de solo, nas camadas 0–75 e 75–150 mm de profundidade, para determinação da densidade, porosidade e capacidade de armazenamento de ar e de água do solo. O pastejo em sistema de lotação contínua, com controle da taxa de lotação animal em função da produção de forragem, não comprometeu a qualidade física do solo. A capacidade de armazenamento de água do solo é um indicador sensível para se avaliarem os efeitos da intensificação da utilização da pastagem sobre a qualidade física do solo.The objective of this work was to evaluate the physical quality of soil in pastures under continuous grazing. The pastures were established with Bermudagrass coastcross (Cynodon dactylon) intercropped or not with the perennial peanut (Arachis pintoi). The intercropped pasture was fertilized with 0, 100 and 200 kg ha-1 nitrogen (N) per year and the single-cropped pasture was fertilized with 200 kg ha-1 N per year, totaling four treatments. The experiment was established in 2002 in a Haplorthox (Rhodic Ferralsol) in Paranavaí, northwestern of Paraná, Brazil, using a randomized complete block design, with two replications. Between 2002 and 2007 the stocking rate was based on forage offer level. In March and November 2007, undisturbed soil samples were collected from 0–75 and 75–150 mm depths for the evaluation of soil bulk density, soil porosity, and soil air and water storage capacity. Continuous grazing with stocking rates controlled as a function of the pasture production did not damage the soil physical quality. The soil water storage capacity is a sensitive indicator to assess the effects of stocking rate intensification on soil physical quality

Behavior of young bulls in confinement housed separately or in group

The objective of this study was to evaluate the behavior of young bulls (between September and October of 2003) and to associate this with their performance. Fifty crossbred animals were divided among three treatments: T1, with a pair of animals in each of 10 pens; T2, with 10 animals in individual stalls; and T3, with 20 animals in a collective pen. An adaptation period was followed by 5 d of observations, with annotations every 15 min between 6:00 and 20:00 h. The observed activities were ingestion, rumination and leisure. Dry and wet bulb temperatures, black glove temperature in shade and in the sun, and relative humidity were recorded at 10:00 and 15: h. Conditions of thermal comfort were also evaluated through the temperature and humidity index (THI). The mean THI value of 78.0 indicated the thermal discomfort of the animals. Time dedicated to ingestion by T1 animals (113.5 min) surpassed that of the other treatments (T2, 88.6 min and T3, 102.1 min). Ruminations time was similar for animals of T1 (121.3 min) and T2 (116.2 min), but greater than that of T3 (100.8 min). Leisure time of T1 animals (185.1 min) was less than those of T2 (215.1 min) and T3 (217.0 min). Animals of all the treatments preferred to ruminate while lying. Time spent lying was greater in individually housed animals (T2) and in those of the collective pen (T3). However, there were no significant differences among the treatments in the weight gain of the animals

Technical and economic indicators of milk production systems in the Caiuá sandstone region

  The aim of this study was to analyze technical and economic indicators of family milk production systems, with different technology levels, in the Caiuá sandstone area in Northwestern Paraná, Brazil. The analysis period covers the agricultural years 2002/2003 to 2013/2014. The categorization of the milk production systems was based on information from agricultural farms monitored by the Reference Network for Family Agriculture. The cost-benefit analysis method was used for the economic assessment of milk production. Based on the results, three family milk production systems were identified in the region, characterized by the use of low, medium and high intensification technologies for pasture management. The production costs per unit area were found to be higher in the system with high technology and lower in the system with low technology. However, although the total revenue in the production system with a high technological intensification is greater than in the other systems, the capital needed for a technological transition is higher. In all the systems, when the costs were deducted, including the return on family labor, there was a profit, even with the climate and soil constraints inherent in the region.