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Development of multi-functional combine harvester with grain harvesting and straw baling

  • Tang, Zhong
  • Li, Yaoming
  • Cheng, Cheng
The decomposition and burning of straw results in serious environmental pollution, and research is needed to improve strategies for straw collection to reduce pollution. This work presents an integrated design of multi-functional rice combine harvester that allows grain harvesting and straw baling. This multi-functional combine harvester could reduce the energy consumption required for rice harvesting and simplify the process of harvesting and baling. The transmission schematic, matching parameters and the rotation speed of threshing cylinder and square baler were designed and checked. Then the evaluation of grain threshing and straw baling were tested on a transverse threshing cylinders device tes rig and straw square bales compression test rig. The test results indicated that, with a feeding rate of 3.0 kg/s, the remaining straw flow rate at the discharge outlet was only 1.22 kg/s, which indicates a variable mass threshing process by the transverse threshing cylinder. Then the optimal diameter, length and rotating speed of multi-functional combine harvester transverse threshing cylinder were 554 mm, 1590 mm, and 850 r/min, respectively. The straw bale compression rotating speed of crank compression slider and piston was 95 r/min. Field trials by the multi-functional combine harvester formed bales with height×width×length of 40×50×54-63 cm, bale mass of 22.5 to 26.0 kg and bale density 206 to 216 kg/m3. This multi-functional combine harvester could be used for stem crops (such as rice, wheat and soybean) grain harvesting and straw square baling, which could reduce labor cost and power consumption.

Whole-plant mineral partitioning during the reproductive development of rice (Oryza sativa L.)

  • Sperotto, Raul A.
  • Vasconcelos, Marta W.
  • Grusak, Michael A.
  • Fett, Janette P.
Minimal information exists on whole-plant dynamics of mineral flow. Understanding these phenomena in a model plant such as rice could help in the development of nutritionally enhanced cultivars. A whole-plant mineral accumulation study was performed in rice (cv. Kitaake), using sequential harvests during reproductive development panicle exertion, grain filling, and full maturity stages in order to characterize mineral accumulation in roots, non-flag leaves, flag leaves, stems/sheaths, and panicles. Partition quotient analysis showed that Fe, Zn, Cu and Ni are preferentially accumulated in roots; Mn and Mg are accumulated in leaves; Mo, Ca, and S in roots and leaves; and K in roots, leaves and stems/sheaths. Correlation analysis indicated that changes in the concentrations of mineral pairs Fe-Mn, K-S, Fe-Ni, Cu-Mg, Mn-Ni, S-Mo, Mn-Ca, and Mn-Mg throughout the reproductive development of rice were positively correlated in all four of the above ground organs evaluated, with Fe-Mn and K-S being positively correlated also in roots, which suggest that root-to-shoot transfer is not driven simply by concentrations in roots. These analyses will serve as a starting point for a more detailed examination of mineral transport and accumulation in rice plants.

External validation of the GrazeIn model of pasture dry matter intake and milk yield prediction for cows managed at different calving dates and stocking rates

  • Roca-Fernández, Ana I.
  • González-Rodríguez, Antonio
The aim was to evaluate the prediction accuracy of pasture dry matter intake (PDMI) and milk yield (MY) predicted by the GrazeIn model using a database representing 124 PDMI measurements at paddock level and 2232 MY measurements at cow level. External validation of the model was conducted using data collected from a trial carried out with Holstein-Friesian cows (n=72) while grazed 28 paddocks and were managed in a 2×2 factorial design by considering two calving dates (CD), with different number of days in milk (DIM), early (E, 29 DIM) vs. middle (M, 167 DIM), and two stocking rates (SR), medium (M, 3.9 cows ha-1) vs. high (H, 4.8 cows ha-1), under a rotational grazing system. Cows were randomly assigned to four grazing scenarios (EM, EH, MM and MH). The mean observed PDMI of the total database was 14.2 kg DM cow-1 day-1 while GrazeIn predicted a mean PDMI for the database of 13.8 kg DM cow-1 day-1. The mean bias was −0.4 kg DM cow-1 day-1. GrazeIn predicted PDMI for the total database with a relative prediction error (RPE) of 10.0% at paddock level. The mean observed MY of the database was 23.2 kg cow-1 day-1 while GrazeIn predicted a MY for the database of 23.1 kg cow-1 day-1. The mean bias was –0.1 kg cow-1 day-1. GrazeIn predicted MY for the total database with a mean RPE of 17.3% at cow level. For the scenarios investigated, GrazeIn predicted PDMI and MY with a low level of error which made it a suitable tool for decision support systems.

Is there a relation between risk rate and the insurance premium in agricultural insurances?. An application to the citrus sector, ¿Existe relación entre la tasa de riesgo y las primas repercutidas en los seguros agrarios?. Aplicación al sector citrícola

  • Vidal, F.
  • Parra, G.
  • López, D.B.
Agricultural insurance has an essential role as a tool for risk reduction. This is especially important in a changing and uncertain environment as in agriculture. Insurance acts as a compensating mechanism of loss and risk transference between insured and insurer. This paper aims to find if there is a concluding relationship amongst the rates applied by insurance companies; the insurance premium applied to the insured farmers; the real risk level that farms face and the indemnifications that farmers get after a disaster. There were 418 citrus tree farms analysed in Murcia region (Spain) in the period 2002-2006. They were in the line called "Multicultivo de Cítricos y Complementario" (Citrus Multi-crop and Complementary). The correlation coefficients of the different analyses are close to zero (between 0.047 and 0.053). This indicates no relation between the real risk and the rate that insurance companies use. The rate is almost a constant, with no dependence on the risk of suffering damage. The main conclusion is that the present agricultural insurance system is not discriminating enough and the settlement of insurance premiums that insurance companies apply does not maintain any relation to the essential element that should direct an insurance contract: the risk that a disaster has occurred., El seguro agrario tiene un papel esencial como instrumento de reducción del riesgo, y más ante un entorno incierto y cambiante como es la agricultura, al servir de mecanismo de compensación de pérdidas y de transferencia de riesgos entre asegurado y asegurador. En este trabajo se pretende encontrar si existe una relación concluyente entre la tasa aplicada por las compañías aseguradoras, y por tanto de la prima aplicada a los asegurados (agricultores), el nivel de riesgo real que sufren las parcelas, y las indemnizaciones recibidas por los agricultores tras un siniestro. Se ha trabajado con 418 parcelas dedicadas al cultivo de cítricos en la Región de Murcia, en el período 2002-2006, y dentro de la línea "Multicultivo de Cítricos y Complementario ". Los coeficientes de correlación de los diferentes ajustes realizados son muy cercanos a cero (entre 0,047 y 0,053), lo que nos indica una ausencia total de relación entre el riesgo real de siniestro y la tasa empleada por las aseguradoras. La tasa es prácticamente una constante, independiente del riesgo de sufrir algún tipo de daño. La conclusión a la que se llega es que el actual sistema de seguros agrarios no es lo suficientemente discriminante y la política de fijación de primas seguida por las compañías aseguradoras no mantiene relación alguna con el elemento esencial que debería marcar cualquier contrato de seguro: el riesgo de ocurrencia de un siniestro.

Compost and vermicompost as nursery pot components: effects on tomato plant growth and morphology, Compost y vermicompost como componentes de sustratos artificiales de cultivo en viveros: efectos en el crecimiento y morfología del tomate

  • Lazcano, C.
  • Arnold, J.
  • Tato, A.
  • Zaller, J.G.
  • Domínguez, J.
Post transplant success after nursery stage is strongly influenced by plant morphology. Cultural practices strongly shape plant morphology, and substrate choice is one of the most determining factors. Peat is the most often used amendment in commercial potting substrates, involving the exploitation of non-renewable resources and the degradation of highly valuable peatland ecosystems and therefore alternative substrates are required. Here the feasibility of replacing peat by compost or vermicompost for the production of tomato plants in nurseries was investigated through the study of the effect of increasing proportions of these substrates (0%, 10%, 20%, 50%, 75% and 100%) in target plant growth and morphological features, indicators of adequate post-transplant growth and yield. Compost and vermicompost showed to be adequate substrates for tomato plant growth. Total replacement of peat by vermicompost was possible while doses of compost higher than 50% caused plant mortality. Low doses of compost (10 and 20%) and high doses of vermicompost produced significant increases in aerial and root biomass of the tomato plants. In addition these treatments improved significantly plant morphology (higher number of leaves and leaf area, and increased root volume and branching). The use of compost and vermicompost constitute an attractive alternative to the use of peat in plant nurseries due to the environmental benefits involved but also due to the observed improvement in plant quality., Tanto las prácticas de cultivo en los viveros como la elección del tipo de sustrato tienen una gran influencia sobre la morfología de las plántulas y por lo tanto en su adaptación post transplante. Aunque la turba es uno de los sustratos más utilizados en viveros, su uso conlleva la explotación de un recurso no renovable y la degradación de las turberas, por lo que se hace necesaria la búsqueda de sustratos alternativos que puedan reemplazarla total o parcialmente. En este trabajo se investigó la posibilidad de reemplazar la turba por compost o vermicompost en la producción de plántulas de tomate, mediante el estudio de los efectos de proporciones crecientes de estos sustratos (0%, 10%, 20%, 50%, 75% y 100%) en parámetros morfológicos y de crecimiento claves para la adaptación post transplante. Compost y vermicompost mostraron ser sustratos adecuados para el crecimiento de las plántulas. La sustitución total de la turba sólo fue posible con vermicompost mientras que las dosis de compost mayores que el 50% produjeron la mortalidad de las plántulas. Las dosis bajas de compost (10 y 20%) y altas de vermicompost, produjeron incrementos signif icativos en la biomasa aérea y radicular de las plantas. Además estas dosis mejoraron de forma significativa su morfología (número de hojas, superficie foliar, volumen y ramificación de las raíces). Compost y vermicompost constituyen alternativas atractivas al uso de turba en la producción de plántulas de tomate no sólo por sus beneficios medioambientales sino también por la mejora significativa de la calidad de las plántulas.

Farmer preference for improved corn seeds in Chiapas, Mexico: A choice experiment approach

  • Sánchez-Toledano, Blanca I.
  • Kallas, Zein
  • Gil-Roig, José M.
Appropriate technologies must be developed for adoption of improved seeds based on the farmers’ preferences and needs. Our research identified the farmers’ willingness to pay (WTP) as a key determinant for selecting the improved varieties of maize seeds and landraces in Chiapas, Mexico. This work also analyzed the farmers’ observed heterogeneity on the basis of their socio-economic characteristics. Data were collected using a semi-structured questionnaire from 200 farmers. A proportional choice experiment approach was applied using a proportional choice variable, where farmers were asked to state the percentage of preference for different alternative varieties in a choice set. The generalized multinomial logit model in WTP-space approach was used. The results suggest that the improved seed varieties are preferred over the Creole alternatives, thereby ensuring higher yields, resistance to diseases, and larger ear size. For the preference heterogeneity analyses, a latent class model was applied. Three types of farmers were identified: innovators (60.5%), transition farmers (29.4%), and conservative farmers (10%). An understanding of farmers’ preferences is useful in designing agricultural policies and creating pricing and marketing strategies for the dissemination of quality seeds.

Yields and chemical composition of different parts of the common vetch of flowering and at two seed filling states, Rendimientos y composición química de los componentes morfológicos de veza común en dos estados de madurez de la semilla

  • Rebolé, A.
  • Alzueta, C.
  • Ortiz, L.T.
  • Barro, C.
  • Rodríguez, M.L.
  • Caballero, R.
In annual forage legumes such as the common vetch (Vicia sativa L.), in which the pods represent a substantial proportion of the total biomass, the optimum harvesting stage may not adjust to the classical model of decreasing nutritive value after flowering. The effect of harvest time on the yield of the main chemical components of common vetch was evaluated under field conditions typical of the Castilian Plain (Mediterranean continental-type climate under rain-fed conditions). Over two growing seasons (1996-1997 and 1997-1998), plants were harvested at flowering and at two stages during seed filling (characterized by a progressively higher dry matter content of the seed; 280 and 380 g kg-1 respectively). The results show that the greater quality and quantity of the pods offsets the decrease in quality occasioned by the aging of the vegetative plant parts (stems plus leaves). Crude protein yields were not affected by delaying the harvest-time. Starch yields were higher when the plant was harvested during seed-filling. Sugar yields increased between flowering and seed filling in the first growing season but decreased in the second. Yields of structural components such as neutral-detergent fibre, acid-detergent fibre and acid-detergent cellulose, followed a pattern similar to that of crude protein. There therefore appears to be a flexible harvest period ranging from flowering until the beginning of seed filling (seeds with 380 g dry matter kg-1), which may be advantageous when trying to select optimum haymaking conditions., En leguminosas forrajeras anuales como la veza común (Vicia sativa L.), en las que la legumbre representa una proporción considerable de la biomasa total, el momento óptimo de corte puede no ajustarse al modelo clásico de disminución del valor nutritivo después de la floración. En este trabajo se evaluó el efecto del momento de recolección de la veza común sobre el rendimiento de los principales constituyentes químicos en condiciones de secano típicas de la Meseta Castellana. Las plantas se cosecharon durante dos años consecutivos (1996-1997 y 1997-1998), en floración y en dos estados de madurez de la legumbre (materia seca de la semilla 280 y 380 g kg-1, respectivamente). Los resultados mostraron que, al avanzar la madurez, la mayor calidad y cantidad de la legumbre contrarresta la disminución de la calidad de las partes vegetativas de la planta. Los rendimientos de proteína bruta no se vieron afectados por un retraso en la fecha de recolección. Los de almidón, sin embargo, fueron mayores al estado de legumbre madura, y los de azúcares aumentaron desde la floración al estado de legumbre en el primer año, mientras que disminuyeron en el segundo año. Los rendimientos de constituyentes estructurales (fibra neutro-detergente, fibra ácido-detergente y celulosa ácido-detergente) siguieron una tendencia similar a los de la proteína bruta. Se concluye que existe un margen de maniobra entre la floración y las primeras fases de formación de la semilla (semilla con 380 g de materia seca kg-1) que permite elegir las mejores condiciones de henificación.

Protective effect of mangrove (Rhizophora apiculata) leaves extract in shrimp (Penaeus monodon) larvae against bio-luminescent disease-causing Vibrio harveyi bacteria

  • Kannappan, Sudalayandi
  • Sivakumar, Krishnamoorthy
  • Sethi, Satyanarayan
Application of chemicals for monitoring if Vibrio outbreaks can enhance resistance in mangrove (Rhizophora apiculata) leaves extract was tested against bioluminescence disease-causing Vibrio harveyi bacteria. An inhibitory zone of 12 mm was observed at 350 µg/mL The growth of V. harveyi was decreased from 0.783 to 0.533 (OD600) as compared to control (0.970 to 1.031 OD) against R. apiculata extract. The extract was treated against virulence produced by V. harveyi, the crude bacteriocin values decreased from 1.653 to 1.574 OD as compared with control. Further, extract 200 mg/mL was challenged against V. harveyi (10 mL at 1.8 OD600) during larviculture of Penaeus monodon for 30 days. The mortality increased from 9.0 to 68.5% in the control, but in the treatment the mortality varied from 0 to 57.8% till 30th day. The difference in the decrease of mortality in the treatments was 10.6%. V. harveyi count was decreased from 1.46 × 105 to 3 × 103 cfu/mL, respectively in the treatment for the 30th day as compared to control (1.33×105 to 9.2×103 cfu/mL). R. apiculata leaves extract was reported to have various functional groups of compounds as determined by Fourier Transform Infrared Spectroscopy (FTIR). The GC-MS analysis revealed that the R. apiculata extract contains compounds such as 1, 2-diacetate, cyclododecane, 2-chloropropionic acid and squalene. These compounds might be responsible for the antagonism against V. harveyi. Hence, crude extracts of R. apiculata can be used as a non-antibiotic agent to control shrimp disease caused by V. harveyi during larviculture.

Frequency of consumption and changing determinants of purchase decision: from attributes to values in the organic food market, Frecuencia de consumo y cambios en los determinantes de la decisión de compra: de los atributos a los valores en el mercado de los alimentos ecológicos

  • Barrena, R.
  • Sánchez, M.
Increasing saturation, maturity and globalisation in the agricultural goods market is forcing suppliers to innovate in order to sustain their business performance. One of the options open to them is to gain a deeper understanding of existing and potential customers in order to develop marketing strategies tailored to meet their priorities. This paper contributes to this option by identifying the food choice process for regular and occasional consumers of organic products. Consumer behaviour is modelling using the means-end chain method, which, as well as consumers’ interest in product attributes also considers their knowledge of themselves and their personal involvement in the organic food choice process. The results show that the purchase choice between both consumer groups. For regular consumers the two main components in the final purchase choice are health and self-image. Therefore market positioning should pay attention to these personal consumer priorities in addtition to the product differentiating features. Break down the cognitive barriers that continue to hamper the development of this market. , El creciente fenómeno de saturación, maduración y globalización de los mercados agroalimentarios, obliga a la oferta al diseño de innovadoras estrategias de actuación, con el fin de conseguir aceptables niveles de rentabilidad de sus negocios. Una de sus opciones potenciales es conocer en profundidad el comportamiento del actual y potencial comprador para adaptar las actuaciones comerciales a sus prioridades. Este trabajo, en este contexto, contribuye identificando el proceso de compra para compradores habituales y ocasionales de alimentos ecológicos. El análisis de dicho comportamiento del consumidor se realiza utilizando la metodología de Means-End Chain, que considera, además del interés por los atributos del producto, el conocimiento de sí mismos que tienen los compradores, y su implicación personal en el proceso de elección en alimentos ecológicos. Los resultados indican que las elecciones de compra difieren entre ambos grupos. Para los consumidores habituales los dos factores claves en la elección de compra son la salud y la buena valoración personal. Pueden, por lo tanto, estos aspectos de la persona ser utilizados tanto en el posicionamiento de mercado como en las actuaciones de diferenciación del producto, reduciendo las barreras del conocimiento que siguen limitando el desarrollo de este mercado  

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