Objetivo. Describir las comunidades planctónicas y bacterianas asociadas al cultivo de bocachico Prochilodus magdalenae con tecnología biofloc (BFT). Materiales y métodos. En nueve tanques rectangulares de concreto con volumen útil de 6.0 m3, se sembraron alevinos de bocachico con peso promedio de 1.6±0.2 g, a tres densidades 5 (T1), 10 (T2) y 20 (T3) peces/m3 con BFT, durante 120 días de cultivo. La identificación y cuantificación de los microorganismos se realizó cada ocho días, en una muestra de 250 ml de agua por tanque, mediante análisis de alícuotas en cámaras Sedgwick-Rafter y/o Neubauer bajo microscopio a 10x y 40x. Los días 15, 45 y 90 del cultivo se caracterizaron las comunidades bacterianas tomando una muestra de 2 g de floc en 90 ml de solución salina estéril y sometidas a pruebas microbiológicas convencionales. Resultados. Se identificaron cinco grupos planctónicos (microalgas, rotíferos, cladóceros, copépodos y protistas con predominancia de ciliados) con mayor cantidad de rotíferos y protistas en los cultivos con menor densidad (T1 y T2); y la mayor afluencia de microorganismos osciló entre 174.9±21.4 ind/ml (T1) y 125.6±16.1 ind/ml (T2). En el grupo de bacterias fue posible identificar 10 cepas: Escherichia coli, Enterobacter sp., Klebsiella sp., Salmonella sp. (Enterobacteriaceae) Bacillus subtilis, Bacillus sp, Lactobacillus sp, Pseudomonas sp (Vibrionaceae), Micrococcus sp, Staphylococcus sp (Cocos gram+). Conclusiones. La composición del plancton fue similar en todos los tratamientos, con rotífero y protistas como los más abundantes; la mayor proporción de bacterias fueron Enterobacterias y Heterotróficas.

Each phytoplankton species presents a different behavior and tolerance to the cryopreservation process. Therefore, in a species-specific protocol, it is essential to ensure both growth and post-thawing cell viability. In this study, we explored the effect of cryopreservation of Scenedesmus sp. with two cryoprotectants, dimethyl sulfoxide (DMSO) and methanol (MET), at 5% and 10% inclusion for each. In the control treatment, the microalgae were not exposed to cryoprotective agents (Control). Three post-thawing cell viability criteria were used: no cell damage (NCD), cell damage (CD), and marked lesions (LM), and mitochondrial and cell membrane damage was evaluated by flow cytometry. The study was a 2 × 2 factorial design, with five replications by treatments, population growth, and cell damage evaluated from the fifth day after thawing. On the fifth day, the highest percentage of NCD was observed when the microalgae were cryopreserved with DMSO 5% (50%); Regarding the control group, it showed 0% NCD. Flow cytometry analysis reveals minor damage at the membrane and mitochondria (9–10.7%) when DMSO is used at both inclusion percentages (5–10%) after thawing. In the exponential phase, the highest growth rates, doubling time, and yield was observed in cryopreserved cells with MET 5%. The results suggest that DMSO 5% is an ideal treatment for cryopreserving microalgae Scenedesmus sp.

The management of the first feeding is a critical stage in the viability of the larvae and fingerling rearing. So far, the first feeding of the bryconids record the best results when fed with forage larvae; thus, the aim was to evaluate two species of cladocerans as live prey in the first feeding of dorada Brycon sinuensis and to evaluate their effects on the control of cannibalism. Larvae (1.2 ± 0.15 mg and 5.9 ± 0.4 mm initial weight and total length) were fed Moina minuta (Mm), Macrothrix elegans (Me) or a mixture (50:50) of cladocerans (Mix) at a rate of 20 prey mL⁻¹, once for 24 h. Another dorada larvae group were fed newly hatched larvae of Piaractus brachypomus (4.5 ± 0.9 mm) as forage larvae (F_L) in a ratio of 2:1 (prey:predator). The larvae were stocked to 50 L⁻¹ in aquaria with 5 L of useful volume (12 per treatment). The growth, survival, stress resistance, cannibalism mortality, and the number of prey in the gut contents were analyzed. Dorada larvae fed F_L showed higher growth, but those fed Mm showed the highest survival rate (76.1 ± 6.6%) and the lowest cannibalism mortality (16.8 ± 3.7%) (p < 0.05). The use of the cladocerans allowed high survival and stress resistance (95.3 ± 2.4%), and M. minuta proved to be a suitable prey for cannibalism control in the management of the first feeding of dorada larvae.

El objetivo de la presente publicación es reunir y facilitar el acceso a conocimientos técnicos de la producción de lima ácida Tahití para pequeños y medianos productores del cultivo, los empresarios del sector, la comunidad académica del área frutícola de nivel profesional y técnico, y los asistentes técnicos agropecuarios del cultivo en Colombia. Por otra parte, también se pretende recopilar información para las instituciones relacionadas con el agronegocio de este cultivo en el país, con el fin de mejorar la competitividad, tanto para el mercado interno como para el de exportación. En la publicación se presentan los últimos resultados de la investigación acerca de la lima ácida Tahití en Colombia, datos detallados sobre las características ambientales de las principales regiones productoras, aspectos botánicos y de recursos genéticos, y sistemas de propagación. Así mismo, se exponen las recomendaciones más relevantes para el manejo del cultivo, incluyendo el aspecto productivo, el componente fitosanitario, las prácticas de manejo agronómico, las recomendaciones de cosecha y poscosecha, y los indicadores económicos y financieros.

Cryopreservation of microalgae is crucial for preserving strains that are valuable for biotechnology and industry. The cryopreservation of Scenedesmus dimorphus is particularly relevant due to its emerging role in sustainable biotechnology, including its high lipid accumulation for biofuel production, adaptability to variable lighting conditions, and potential for biomass generation in large‐scale photobioreactors. This study evaluates the response of S. dimorphus to two common cryoprotectants, dimethyl sulfoxide (DMSO) and methanol (MeOH), used at concentrations of 5% and 10%. Cell viability post‐thaw was assessed through three criteria: no cell damage (NCD), cell damage (CD), and marked lesions (ML), with flow cytometry to measure damage to mitochondria and cell membranes. The study followed a 2 × 2 factorial design with five replications per treatment, evaluating population growth and CD from the fifth day post‐thaw. Findings indicated that methanol (MET) at 5% or 10% supported moderate population growth, suggesting it as a potential alternative for cryopreservation in S. dimorphus . However, S. dimorphus showed greater susceptibility to CD and lesions than other species in the same genus, highlighting the need for species‐specific protocols to optimize post‐thaw viability. This research underscores the importance of tailored cryopreservation strategies for different microalgae species.