Scielo RSS http://www.scielo.org.co/rss.php?pid=0120-281220090001&lang=es vol. 58 num. 1 lang. es http://www.scielo.org.co/img/en/fbpelogp.gif http://www.scielo.org.co http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-28122009000100001&lng=es&nrm=iso&tlng=es RESUMEN Se evaluaron en invernadero en un suelo de Matazul, Meta, Colombia durante 6 semanas, 2 genotipos de Brachiaria (uno mejor adaptado a bajo P, B. decumbens y otro menos adaptado, B. ruziziensis) y 8 progenies del cruzamiento entre ellos ( mejores adaptados: H-7, H-40, H-28, H-58; menos adaptados: H-190, H-94, H-82, H-179). Los genotipos mejor adaptados presentaron mayor biomasa aérea, explicada por mayor área foliar, mayor absorción de P en el tallo y mayor volumen de raíz. Las características morfológicas de las raíces, principalmente longitud, peso seco y contenido de P, permiteron mejor adaptación a bajo P disponible en el suelo. El periodo de evaluación fue suficiente para observar diferencias entre progenies.<hr/>Two Brachiaria genotypes (Brachiaria decumbens, considered as better adapted and Brachiaria ruziziensis, considered as less adapted) and 8 progenies from the cross of these two (H-7, H-40, H-28 and H-58 more adapted; H-190, H-94, H-82 and H-179 less adapted) were evaluated during 6 weeks to detect differences in shoot and root attributes when grown in an acid soil from Matazul, Meta, Colombia. Results indicated that better adapted genotypes to low P had more shoot biomass, this could be explained by a greater leaf area, more P uptake in the stem and greater root volume. The root attributes, root length, root dry weight and root P content contributed to greater adaptation to low P availability in acid soils. Six weeks of plant growth was not adequate time to distinguish differences in adaptation to low P among the two parents, but it was adequate time to identify superior progenies from the crosses. http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-28122009000100002&lng=es&nrm=iso&tlng=es Combining ability analysis for grain yield and its components was carried out in eight parental diallel crosses of bold grained rice excluding reciprocals. The general combining ability (GCA) and specific combining ability (SCA) effects were significant for all the characters indicating the importance of both additive and non-additive gene effects in their inheritance. The parents Ranjit followed by Matonga and Monohar Sali contributed significantly to high GCA effect towards high grain yield per hill. The superior specific cross combinations for high grain yield per hill were Matonga/Bar Madhava, originated from high x low GCA combination followed by Dhola Mula/ Ranjit (low x high gca), Chandmoni/Hathi Sali (low x high GCA), Dhola Mula/Mala (low x low gca), Matonga/Mala (high x low GCA), Bar Madhava/Hathi Sali (low x high GCA) and Matonga/Hathi Sali (high x high GCA). Further, these crosses exhibited high SCA effects for some other characters as well. http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-28122009000100003&lng=es&nrm=iso&tlng=es La población S1 de la variedad tailandesa de yuca MTAi8 (AM320), la cual presenta patrones de segregación definidos para el contenido de carotenos totales (Beta-caroteno), se sometió a un análisis de agrupamiento segregante (BSA = Bulk Segregant Analysis) empleando 700 marcadores moleculares tipo microsatélites o SSR. Se generaron 25 grupos de ligamiento identificando 3 QTL mayores asociados con una región del genoma de yuca con el contenido de carotenos totales. Tres marcadores SSR explicaron el 37.2% (NS109), 32% (rSSRY251) y 27.7% (rSSRY313) de la varianza fenotipica total, situados en el grupo de ligamiento D fuertemente asociados con el contenido de carotenos totales en la familia AM320 S1, se estableció una fuerte correlación positiva entre color de pulpa de raíz y contenido de carotenos totales (r=0.81), y negativa entre carotenos totales y materia seca (r= -0.31). Los tres posibles QTL presentaron efecto positivo y de carácter aditivo para el contenido de carotenos totales, pueden ser la oportunidad para implementar selección asistida por marcadores para carotenos totales en yuca.<hr/>The S1 population of the Thai variety MTAi8 (AM320), which shows patterns of segregation defined by the content of total carotenes (beta-carotene), underwent an analysis of segregating bulk (BSA = Bulk segregating Analysis) using 700 molecular markers type microsatellites or SSR. There were generated 25 tying groups and identifying 3 major QTLs associated with a region of the genome of cassava with the content of total carotenes. Three markers SSR; explained the 37.2% (NS109), 32% (rSSRY251) and 27.7% (rSSRY313) of the total phenotypic variance, placed in the Group D strongly tying, associated with the content of total carotenes in the family AM320 S1, which established a strong positive correlation between color and content root pulp carotenes total (r = 0.81), and between negative and carotenes total dry matter (r = -0.31). The three possible QTLs showed positive and additive effect for the content of totals carotenes and could be an opportunity to implement assisted selection markers for total carotenes in cassava. http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-28122009000100004&lng=es&nrm=iso&tlng=es En un diseño de bloques incompletos 10 x 10 con tres repeticiones se estudiaron descriptores cuantitativos relacionados con producción por planta, contenido de capsaicina y presencia de virus en 100 accesiones de Capsicum pertenecientes a la Universidad Nacional de Colombia. Las diferencias entre las accesiones fueron explicadas por el contenido de capsaicina, características asociadas con la producción por planta y características del fruto. Se encontró correlación inversa entre el contenido de capsaicina y producción; número de frutos por planta con peso de fruto. La dispersión de las accesiones en el plano cartesiano situó las variedades comerciales Cayenne, Tabasco y Habanero, en función de producción, peso y cantidad de frutos, en posiciones desventajosas con respecto a los promedios generales de las características de las otras accesiones. Cuatro accesiones superaron a Tabasco en contenido de capsaicina. Cuatro tipos de virus (potyvirus, geminivirus y cucumovirus y virus del mosaico del tabaco TMV) se presentaron en el lote de evaluación. Los virus actuaron en forma conjunta; los potyvirus con los cucumovirus y TMV; los geminivirus con TMV.<hr/>100 accessions from Capsicum gene Bank of the National University of Colombia at Palmira's campus, under field conditions of the experimental station at Candelaria, Cauca Valley were studied. In a design of incomplete blocks 10 x 10 with three repetitions, quantitative descriptions were evaluated. The characteristics were related with yield, capsaicin content and virus presence.The agronomic evaluation found that the differences among the accessions are explained for the capsaicin content, yield, characteristics associated and fruits characteristics associated. Inverse correlation among the capsaicin content with production, quantity of fruits for plant with weight was found. The dispersion of the accessions in the Cartesian axis placed the commercial varieties: Cayenne, Tabasco and Habanero in terms of yield, weight and number of fruits in unfavorable positions with regard to the general averages. The same was observed for the stability of the characteristics above mentioned. There were four introductions with high capsaicin contents that overcome Tabasco. Four virus types affecting plants were evaluated: potyvirus, geminivirus, cucumovirus and virus of the mosaic of the tobacco (TMV). The viruses were acting together; the potyvirus with the cucumovirus and TMV and geminivirus with TMV. http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-28122009000100005&lng=es&nrm=iso&tlng=es Se compararon tres medios de cultivo para seleccionar el apropiado para la regeneración in vitro de la variedad de tomate UNAPAL-Arreboles. Se evaluó la producción de callos/explante, brotes/explante y plántulas /explante. El análisis de varianza y la prueba de Duncan permitieron concluir que el medio M3 presentó los mejores promedios para las variables evaluadas.<hr/>The main objective of this research was to carried out the comparison of three culture medium of major use for in vitro regeneration of tomato, to select the more appropriate medium for in vitro regeneration of tomato, variety UNAPAL-Arreboles. The analysis of variance and media comparison was made based on the callus, shoots and plantlets production. The highest efficiency of callus, shoots and plantlets production was obtained with the M3 media. http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-28122009000100006&lng=es&nrm=iso&tlng=es Con el fin de evaluar el impacto de largos periodos de uso del terreno en propiedades estructurales del suelo, se realizó un muestreo a 0-20 cm de profundidad en los siguientes tratamientos: Suelo no intervenido 25% de pendiente (testigo), uso en pastura por 25 años 25% de pendiente y uso agrícola rotación trigo-maíz (rt-m) de 25, 45 y 70 años de uso a 12% y 25% de pendiente, en un Inceptisol de la zona de reconversión del cultivo de trigo de Nariño (2.400 a 2.800 msnm), Colombia (longitud 75º 14' oeste, latitud 0.5º 10' norte, 2710 msnm, 80% HR, 12ºC). Los resultados mostraron diferencias significativas entre el tipo e intensidad de uso del suelo por largos periodos en distribución de tamaño de agregados secos al aire, estabilidad de agregados al agua y distribución de tamaño de poros. El incremento de la intensidad de uso disminuyó la estabilidad estructural y afectó la porosidad del suelo. El porcentaje de agregados estables al agua mayores a 2.0 mm fue significativamente mayor en suelo no intervenido (51.5%). El cambio a uso agrícola (rt-m) durante 25, 45 y 70 años disminuyó los agregados estables mayores a 2.0 mm a 36.9%, 35.3% y 29.1% respectivamente. La porosidad total del uso en pastura disminuyó en 18% respecto al testigo y tendió a disminuir al aumentar la intensidad de uso del suelo rt-m.<hr/>To evaluate the impact of different land use systems for long periods of time on soil structural properties, a sampling to 0-20 cm of depth was carried in the following treatments: Forest 25% slope (control), pasture crops for 25 years with 25% slope and use agricultural wheat-corn (rw-c) of 25, 45 and 70 years of use, each one of these last, with 12% and 25% slope, in a Inceptisol (Dystric haplustepts) of the area of reconversion of the wheat cropping area located at 2.400 to 2.800 masl in the Andean zone of the department of Nariño, Colombia (longitude 75º 14' west, latitude 0.5º 10' north, 2710 msnm, 80% RH, 12ºC). Results showed significant differences between the type and intensity of soil use for long periods of time in aggregate size distribution, aggregate stability and pore size distribution. The increment of the intensity of soil use, decreased its structural stability and affected soil porosity. The percentage of water stable aggregates larger than 2.0 mm was significantly higher in not intervened soil. The control had 51.5% of water stable aggregates larger than 2.0 mm. Change to agricultural use (rw-c) during 25,45 and 70 years, decreased the stable aggregates larger than 2.0 mm, to 36.9%, 35.3%y 29.1% respectively. The change of forest to pasture, decreased the total porosity in 18%. The agricultural use (rw-c) through the time, generated gradual decrease of the total porosity. http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-28122009000100007&lng=es&nrm=iso&tlng=es Con la aplicación de vinaza, residuo de la producción de alcohol carburante a partir de la caña de azúcar, se evaluó el efecto sobre la actividad y biomasa microbiana del suelo y el suministro de K+ al cultivo de maíz dulce (Zea Mays) en un Entic Dystropept y un Fluventic Haplustoll del Valle del Cauca, Colombia. Se utilizó un diseño completamente al azar con cuatro tratamientos y cinco repeticiones: T1 (100% requerimiento de K+ con KCl), T2 (100% requerimiento de K+ con vinaza), T3 (50% requerimiento de K+ con KCl +50% con vinaza) y T4 (25% requerimiento de K+ con KCl +75% con vinaza). Se estimó biomasa microbiana por el método de fumigación-extracción. Se realizó análisis de varianza, prueba de comparación de medias, regresiones y correlaciones (SAS). Se presentaron diferencias significativas en la actividad y biomasa microbiana por época de muestreo y entre los diferentes muestreos; al final del cultivo el Entic Dystropept presentó el contenido más alto de biomasa microbiana-C en el T2, mientras que en el Fluventic Haplustoll fue en el T1. El menor qCO2 fue para el T2 del Entic Distropept y T1 del Fluventic Haplustoll, estos tratamientos presentaron mayor acumulación de biomasa en cada suelo respectivamente T2 (30 450 kg ha-1) y T1 (21 015.6 kg ha-1).<hr/>With the vinasse application, a residue from the production of fuel ethanol from sugarcane, the effect on the activity of soil microbial biomass an the supply of K+ to crop sweet corn (Zea Mays) in two soils of the Cauca Valley, Colombia were evaluated: Entic Dystropept and Fluventic Haplustoll . Was used a completely randomized design with four replications and five treatments: T1 (100% requirement of K+ with KCl), T2 (100% requirement of K+ with vinasse), T3 (50% requirement of K+ with KCl + 50% with vinasse), T4 (25% requirement of K+ with KCl +75% with vinasse). The microbial biomass was estimated by the fumigation-extraction method. The results were evaluated using analysis of variance, mean comparison test and correlation and resgression (SAS). There were significant differences in the activity and microbial biomass-C by sampling time and among deferent samples. At the end of the crop, the Entic Dystropept had higher content of microbial biomass-C at T2, while in the Fluventic Haplustoll showed higher content in T1. The lowest qCO2 was for the Entic Distropept at T2 and T1 in Fluventic Haplustoll. These treatments had a greater accumulation of biomass in each soil respectively T2 (30 450 kg ha-1) and T1 (21 015.6 ha kg-1). http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-28122009000100008&lng=es&nrm=iso&tlng=es La fauna de hormigas asociada con la zoocría de mariposas en los departamentos de Valle del Cauca y Quindío (Colombia), se colectó por captura manual en tres ambientes (mariposario, vivero y laboratorio). De 125 muestras se extrajeron 779 hormigas, pertenecientes a cinco subfamilias, 18 géneros y 24 especies. El mayor número de especies se registró en el área de laboratorio (17), seguido por vivero (16) y mariposario (13). No se encontraron diferencias significativas (Chi² = 6.019, g.l.= 10, P>0.75), al evaluar la preferencia de las hormigas por un ambiente, sin embargo se observaron tendencias de esta manera: Wasmannia auropunctata (50%), Linepithema sp. (47%), Monomorium floricola (40%) fueron las más importantes en el laboratorio, mientras que en el mariposario fueron Linepithema humile (42%), Camponotus novogranadensis (39%) y Paratrechina longiconis (37.5%) y en el vivero W. auropunctata (37.5%) y P. longicornis (37.5%). Algunas de estas hormigas son reconocidas como vagabundas y plagas urbanas, lo que podría considerarse como un riesgo potencial para las actividades de zoocría de mariposas. En el presente estudio se propuso conocer las especies de hormigas que se asocian con tres criaderos de mariposas localizados en el suroccidente colombiano.<hr/>The ant fauna associated to the butterflies rearing in the departments of Cauca Valley and Quindio (Colombia) was studied. The ants were collected using manual capture method in three different environments (butterfly garden, nursery and laboratory). 779 ants were extracted from 125 samples, which belonged to five sub-families, 18 genera and 24 species. The greatest number of species were registered at the laboratory (17), followed by nursery (16) and butterfly garden (13). There weren't any significant differences (Chi2 = 6.019, d.f.= 10, P> 0.75), in assessing the preference of ants for some environment, however some trends were observed, on this way: at the lab Wasmannia auropunctata (50%), Linepithema sp. (47%), Monomorium floricola (40%) were the most important species, while at the butterfly garden were Linepithema humile (42%), Camponotus novogranadensis (39%) and Paratrechina longiconis (37.5%) and W. auropunctata (37.5%) and P. longicornis (37.5%) at the nursery. Some of these ants have been recognized as tramp ants and urban pests, which could be considerate as a potential risk for butterfly rearing activities. In this research, we expected recognize the ants species associated in three butterflies rearing located in the southwest of Colombia. http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-28122009000100009&lng=es&nrm=iso&tlng=es El cultivo de algas mixtas se realizó en el Instituto de Piscicultura Tropical de la Corporación Autónoma Regional del Valle del Cauca (Buga 25 ºC y 969 m.s.n.m.) utilizando fertilizantes inorgánicos en baldes plásticos, se produjeron en promedio 386 x 10³ células/ml de cultivo. En el cultivo de Philodina en frascos de vidrio alimentado con algas y levadura, se obtuvieron 410 rotíferos/ml de cultivo. Se evaluaron tres tratamientos: rotíferos enriquecidos con aceite de pescado; rotíferos más algas (Chlorella, Scenedesmus, Pediastrum, Spyrogira y Anabaena) y Artemia salina + Spirulina, usando 100 post-larvas de bocachico/acuario, alimentadas dos veces al día según biomasa sembrada. El mayor porcentaje de sobrevivencia, peso y talla se obtuvo con el alimento constituido por rotíferos enriquecidos con aceite de pescado (93 %,3.2mg, 6.86mm)), seguido de rotíferos + algas (80.67 %,2 mg, 6.1mm) y Artemia+ Spirulina (60.6 %,1.6mg, 6.06mm) respectivamente<hr/>In the Tropical Piscicultural Institute of the Regional Autonomous Corporation of Buga, Cauca, Valley, Colombia (25ºC temperature, 969 m a s l,) a research was carried out with the objective to produce and use algaes and rotifers (living food) cultures to feed bocachico post-larvas (Prochilodus reticulatus magdalenae). A complete random design with three treatments and three repetitions was established. 100 bocachico/aquarium post larva were used and fed twice a day according to sown biomass. The cultures of mixed algaes were established by using inorganic fertilizers produced in plastic pails and obtaining an average of 386 x 10³ cells/ml of culture. On the other hand, the cultures of Philodina rotifers were established in glass bottles and feeding them with algaes and yeast. An average of 410 rotifers/ml of culturing was obtained . To evaluate the highest rate of survival, growing and weight of bocachico post-larvas, three kind of food were used: Rotifers enriched with fish oil; rotifers plus algaes (Chlorella, Scenedesmus, Pediastrum, Spyrogina and Anabaena) and only Artemia salina and Spirulina. The highest survival, weight and size percentage was obtained with food formed of rotifers enriched with fish oil (93% 3.2mg, 6.86mm) respectively, followed by rotifers + algaes (80.67%, 2mg, 6.1mm) and Artemia + Spirulina (60.6%, 1.6mg, 6.06mm).