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The sugar industry is an ideal sector for electricity cogeneration due to a large amount of burnable bagasse produce as a by-product. Bagasse produced in the sugar industry always consists of moisture affecting the efficiency of a boiler in the cogeneration plant. In our case study, a cogeneration plant run by bagasse burning found with bagasse moisture problem and suffocating with low power generation for the last few years. The boiler efficiency per tonne of bagasse is currently lower than optimal due to the substantial percentage of water present in the bagasse. A bagasse dryer design for this industry can improve the efficiency of a boiler as well as the cogeneration plant. In this paper, a pneumatic bagasse drying system is proposed to reduce the moisture content of bagasse from 48% to 30%. This work provides a full analysis of bagasse dryer design parameters, including specifications for dryer system components, such as feeders, fan, drying tube, and cyclone. The total bagasse drying system proposed is expected to be fitted within a 6 x 6 x 25 m space to dry 60 tph of bagasse, reducing the moisture content from 48% to 30%, in full compliance with all relevant Australian and company standards. Resumen La industria azucarera es un sector ideal para la cogeneración eléctrica debido a la gran cantidad de bagazo que se produce como subproducto. El bagazo producido en la industria azucarera siempre consiste en humedad que afecta la eficiencia de una caldera en la planta de cogeneración. En nuestro caso de estudio, una planta de cogeneración operada por la quema de bagazo se encontró con un problema de humedad del bagazo y asfixiada con baja generación de energía durante los últimos años. La eficiencia de la caldera por tonelada de bagazo es actualmente inferior a la óptima debido al porcentaje sustancial de agua presente en el bagazo. Un diseño de secador de bagazo para esta industria puede mejorar la eficiencia de una caldera y de la planta de cogeneración. En este trabajo, se propone un sistema de secado neumático de bagazo para reducir el contenido de humedad del bagazo del 48% al 30%. Este trabajo proporciona un análisis completo de los parámetros de diseño del secador de bagazo, incluidas las especificaciones de los componentes del sistema del secador, como alimentadores, ven tiladores, tubos de secado y ciclones. Se espera que el sistema de secado total de bagazo propuesto se instale en un espacio de 6 x 6 x 25 m para secar 60 tph de bagazo, reduciendo el contenido de humedad del 48% al 30%, en total cumplimiento con todas las normas relevantes de Australia y de la empresa.

Resumen El color es uno de los atributos sensoriales que mejor define la calidad de un alimento, no obstante las investigaciones sobre el color superficial de pulpa de frutos de musáceas en Colombia son escasas. Esta información es de gran utilidad para identificar materiales promisorios destinados para consumo fresco y procesamiento agroindustrial. En este estudio se caracterizó el color superficial de la pulpa de 25 accesiones de plátano Musa sp. (Musaceae) del Banco de Germoplasma de Musáceas del Sistema de Bancos de Germoplasma de la Nación para la Alimentación y la Agricultura (SBGNAA) existente en la Corporación Colombiana de Investigación Agropecuaria (Agrosavia) en Palmira, Colombia. Las coordenadas CIEL.a.b. fueron determinadas por triplicado utilizando un colorímetro, entre ellas se calcularon parámetros de cromaticidad (C*), tonalidad (h°) y diferencia de color (AE). Las accesiones de plátano presentaron rangos de L*(17.31-79.30), a*(8.73-30.64). y b*(15.24-95.49), C*(17.77-98.22), h°(38.24-81.00) y AE*(147.07-6851.24). Las pulpas de plátano fueron clasificadas colorimétricamente entre amarillos tenues a amarillos intensos. La variación de las coordenadas colorimétricas a*, h°, y AE se ajustaron a una cinética de orden cero; y L*, b* y C* describieron una cinética de primer orden. Las accesiones Benedetta, Cachaco espermo, Cachaco sin bellota, Dominico mocho, Dominico mutante, GAEP-2, Hartón tigre y Maia Maoli Risaralda, fueron clasificadas como materiales promisorios para consumo en fresco o procesos agroindustriales, por los bajos valores de la constante de velocidad cinética (k) registrados en el presente estudio. Abstract Color is one of the sensory attributes that best define the quality of a food, however, to date there are no scientific investigations that record the study of superficial color of the fruit pulp of Musaceae, which provides useful information to identify promising materials destined for fresh consumption and agroindustrial processing. Surface color of plantain, Musa sp. (Musaceae) pulp from the Musaceae Germplasm Bank of the Corporación Colombiana de Investigación Agropecuaria (Agrosavia) was characterized. The CIEL.a.b. coordinates of the pulp of 25 plantain accessions were determined in triplicate using a colorimeter. From the coordinates of the surface color, parameters of chromaticity (C*), hue (h°), and color difference (ΔE) were calculated. Plantain accessions presented a range of L* (17.31-79.30), a* (8.73-30.64), and b* (15.24-95.49), C* (17.77) -98.22), h° 38.24-81.00) and ΔE* (147.07-6851.24). The plantain pulps can be classified colorimetrically among mild to intense yellows. Variation of the colorimetric coordinates a*, h°, and ΔE were adjusted to zero-order kinetics, and L*, b* and C* described a first-order kinetics. Accessions Benedetta, Cachaco espermo, Cachaco sin bellotae, Dominico mocho, Dominico mutant, GAEP-2, Hartón tigre and Maia Maoli Risaralda, are reported as promising materials for fresh consumption or agroindustrial processes, due to the low values of the constant speed kinetics (k) recorded in the present study.

For each vegetable species, there is a specific environment conditions to occur the seed germination process. However, there is a little information regarding the necessary conditions for Niger (Guizotia abyssinica (L.f.) Cass.) seeds germination. The aim of this research was to evaluate the influence of different temperatures and types of light on Niger (Guizotia abyssinica (L.f.) Cass.) seeds germination. Seeds were sown on two sheets of “germitest” paper inside plastic box type “gerbox” and placed on B.O.D. Treatments were constituted of two constant temperatures (15 ºC and 25 ºC, respectively) and an alternating temperature (20-30 ºC) under 10 hours for the lowest temperature and 14 hours for the highest temperature and they were associated to the wavelengths as follows: blue (440 nm), green (560 nm), red (660 nm), extreme red (730 nm), white light and dark. The experiment was conducted in a completely randomized design with four replicates of 50 seeds. Effects of different temperatures and qualities of light were evaluated by seeds germination and vigor. Higher germination of Niger seeds is observed in temperatures of 25 and 20-30 ºC and they can be considered as non-photoblastic. For each vegetable species, there is a specific environment conditions to occur the seed germination process. However, there is a little information regarding the necessary conditions for Niger (Guizotia abyssinica (L.f.) Cass.) seeds germination. The aim of this research was to evaluate the influence of different temperatures and types of light on Niger (Guizotia abyssinica (L.f.) Cass.) seeds germination. Seeds were sown on two sheets of “germitest” paper inside plastic box type “gerbox” and placed on B.O.D. Treatments were constituted of two constant temperatures (15 ºC and 25 ºC, respectively) and an alternating temperature (20-30 ºC) under 10 hours for the lowest temperature and 14 hours for the highest temperature and they were associated to the wavelengths as follows: blue (440 nm), green (560 nm), red (660 nm), extreme red (730 nm), white light and dark. The experiment was conducted in a completely randomized design with four replicates of 50 seeds. Effects of different temperatures and qualities of light were evaluated by seeds germination and vigor. Higher germination of Niger seeds is observed in temperatures of 25 and 20-30 ºC and they can be considered as non-photoblastic.

In this paper we present the bases for the aseptic establishment of Monstera acuminata Koch and Monstera deliciosa Liebm (Araceae) from leaves and the induction of in vitro organogenesis of M. acuminata K. from discs of stems of young shoots. Different disinfection protocols were applied to mature leaves and young shoots, from which foliar explants of 1 cm2 of both species were extracted, and stem disks approximately 1 mm of thick in M. acuminata K. The explants were established in semi-solid media with different hormonal treatments during the stage of aseptic establishment and induction of organogenesis. Disinfection with 3 % of sodium hypochlorite (NaClO) for 20 min and 50 % Murashige y Skoog medium (1962) with PPM, led to less oxidation in the leaf explants of both species. All the explants in the two treatments belonging to M. deliciosa, grown in medium added with PPM and different disinfection protocols, survived, did not present contamination and more than 80 % maintained answer’s capacity until 49 days of culture. After 35 days of culture, with disinfection in Tween 20 + Ethanol 20% + 2.5% NaClO, and sowing of the explants in the MS medium added with 1 mg/l of BAP, 0.5 mg/l of AIA and 0.1 mg/l of ANA were indueces seven new shoots of stem disks. M. deliciosa had better ability to adapt to in vitro conditions. Advances in the establishment and induction of organogenesis in native araceas for wicker production are the basis for ex situ conservation of local populations.

The aim of this study was to compare two methods of estimating leaf area (leaf area meter LI-COR 3100 and ImageJ software) in oats. Renascem black oats and UTF Iguaçu white oats cultivars were evaluated. All the leaves of one plant per plot, with six repetitions, were evaluated every seven days to obtain five assessments for each cultivar. The leaves were identified and fixed on a white A4 sheet of paper with an indication of a known area (45 cm²), photographed and evaluated using a leaf area meter (LI-3100 - LI-COR). Leaf area was then estimated using ImageJ software. Estimates were obtained for standard deviation and coefficient of variation, and a simple linear regression equation was estimated based on the two estimation methods. Mean variances were tested using the ‘F’-test and the means compared by the ‘t’-test. There was no difference between the leaf areas found by both methods. In addition, they were highly correlated, and variances were homogeneous. We concluded that ImageJ software can be used instead of the leaf area meter on the two oat cultivars evaluated.

This paper presents the conceptualization, methodological adjustment and experimental application of the micrometeorological technique eddy covariance - EC, to measure energy, water vapor and CO2 fluxes in two coffee agroecosystems: the first under full sunlight, and the second under shade, both with equatorial Andean hillslope conditions. With a footprint and fetch calculation, the required distance from the edge of the field in the prevailing wind direction to the EC tower is three times higher under shade than full sun. The shaded agroecosystem reached maximum average carbon fixation rates of 21.26 ± 2.469 μmolCO2.m-2s-1 ( = 0.05) (61% higher than under 100% sunlight) which gives a high carbon sink capacity to the association of coffee plants with shading Pigeon peas (Cajanus cajan L). The average evapotranspiration rate was 2.33 ± 0.0102 mm.d-1 ( = 0.05) and 2.08 ± 0.00732 mm.d-1 under shade and 100% sunlight, respectively. The proportion of net radiation that reached the soil was 2% under shade and 4% under 100% sunlight. Likewise, the soil energy loss during the night was lower under shade, indicating less day-night temperature range in the latter agroecosystem. The methodological adjustment and the results of this first work using EC in Colombian coffee plantations, contribute to the development of reliable research regarding gas and energy exchanges between the atmosphere and ecosystems in conditions of the equatorial Andean hillslope.