Universidad de Ciego de Ávila

Nanoparticles, typically from 1 to 100 nm in size, have unique physical and chemical properties that allow them to penetrate biological barriers, making them effective in plant biotechnology for delivering genes, nutrients, and pesticides. Absorbed through roots, leaves, or seeds, they move through the vascular system, enhancing agricultural practices and productivity. Their applications include gene delivery with gold nanoparticles, nanofertilizers for efficient nutrient delivery, and silver nanoparticles for effective pest control, representing significant advancements in sustainable agriculture. However, challenges such as potential toxicity to plants and non-target organisms, high production costs, and environmental impact are the uncertainties that require further research for safe and widespread adoption. Emerging trends include smart nanocarriers that respond to environmental triggers and biodegradable nanoparticles to minimize environmental accumulation. Future research aims to enhance delivery precision and integrate nanotechnology with tools like CRISPR-Cas9 and machine learning for advanced crop management, potentially revolutionizing plant biotechnology and boosting global food security. A study on Stevia rebaudiana revealed that using silver nanoparticles (AgNPs: Argovit™) in temporary immersion bioreactors (TIBs) improved propagation and stimulated secondary metabolite production. Specifically, 25.0 and 37.5 mg L−1 AgNPs reduced shoot multiplication, while 12.5 mg L−1 enhanced endogenous diterpene levels. Similarly, applying AgNPs in TIBs to Gerbera jamesonii increased vase life by 21%, suggesting a potential method for extending the post-harvest longevity of cut flowers. Further research will explore these findings in the context of biotic and abiotic stress.

Invasive plants are characterized by rapid growth and multiplication; absence of natural predators; high adaptability; long-lived seed production; and competition for resources. Eichhornia crassipes; Acacia spp.; Carpobrotus edulis; Dichrostachys cinerea; Ulex europaeus; Ailanthus altissima; Azolla spp.; Buddleja davidii; Cortaderia selloana; and Caulerpa taxifolia are specially problematic in tropical countries. Abiotic factors like temperature, light, moisture, soil pH, and nutrient availability play a crucial role in the spread and success of invasive plants. Soil salinization is a process where soluble salts accumulate in the soil, negatively affecting vegetation. In tropical countries, this phenomenon can significantly impact invasive plants. The main invasive aquatic plants found in Ciego de Ávila, Cuba, are water hyacinth (Eichhornia crassipes) and water lettuce (Pistia stratiotes). This mini-review summarizes the effects of salinity, under controlled experimental conditions, on the levels of chlorophylls (a, b), carotenoids, soluble phenolics, cell wall-linked phenolics, malondialdehyde and other aldehydes.

BACKGROUND: The long-term preservation of plant germplasm is critical to ensure a pool of genetic diversity for future breeding efforts and for conservation management.Although it is important to assess whether the biochemical properties and vigour of the germplasm remain unchanged. OBJECTIVE: To investigate the potential effects of cryopreservation in liquid nitrogen (LN) as a strategy for conservation of carrot. RESULTS: Seeds were exposed to cryogenic temperatures and growth and development was monitored in Petri dishes (for up to 14 days) and in a pot trial (90 days). By day 7, 53% control seeds had germinated compared with 70% seeds exposed to LN. Biochemical attributes were also assessed. Initial differences were observed in the growth rate of plants, where plants originating from seeds exposed to LN emerged faster than those originating from control seeds. However, at the end of the pot trial, differences were only observed in belowground biomass (i.e., mass of carrots). Biochemical evaluations showed that carotenoids and cell wall-linked phenolics were elevated in carrots produced from seeds exposed to LN. CONCLUSION: Overall, the results show that cryopreservation can be used as a viable strategy for long-term preservation of carrot germplasm.

Discriminant analysis is a powerful statistical technique used in plant biotechnology for various applications. In this research, five NaCl concentrations as supplements to the sugarcane culture medium in temporary immersion bioreactors (TIBs) were evaluated. Shoot multiplication rate, shoot cluster fresh weight, and levels of aldehydes, carotenoids, phenolics, and chlorophylls were evaluated. Additionally, soluble phenolic concentration was evaluated in the culture medium. Observations indicated that control TIBs (0 mM NaCl) did not exhibit stress symptoms, whereas TIBs with 200.0 mM NaCl were clearly stressed. These two contrasting treatments were utilized to derive Fisher’s linear discriminant function. In contrast, treatments with 50.0, 100.0, and 150.0 mM NaCl displayed intermediate phenotypes. The goal of this report was to determine the NaCl concentrations that induced stress in sugarcane plantlets using discriminant analysis. Fisher’s linear discriminant function successfully distinguished between the two categorical groups: non-stressed plantlets (0 mM NaCl) and stressed plantlets (200.0 mM NaCl). Based on the magnitude of the coefficients in Fisher’s function, increases in the contents of malondialdehyde and other aldehydes were strong indicators of plant stress. Conversely, increases in soluble phenolics, shoot multiplication rate, and fresh weight of shoot clusters indicated non-stressed plant conditions. Results showed that 50.0 and 100.0 mM NaCl caused only mild stress, classifying these treatments as non-stressed plants. However, sugarcane plantlets cultivated in 150.0 mM NaCl TIBs were classified as stressed plants. The application of discriminant function analysis in this report highlights the saline eustress observed in sugarcane cultivated in TIBs.

The objective of this article is to provide information on the historical aspects, myths, beliefs, use, and management of water by Cuban society from the past to the present. Additionally, it aims to facilitate an assessment of the potential impacts of climate change on water resources, through a documentary analysis of specialized literature, consultations with publications in various media, textbooks, and written press. A documentary compilation is provided on subsistence activities and water resources at various stages of Cuban society's development. The compilation also includes considerations on the impact of climate change on these resources.

Pineapples are highly susceptible to “Wilt disease”, caused by the biotrophic insect Dysmicoccus brevipes that also transmits several Wilt-associated viruses (PMWaVs). Conventional farms manage mealybugs and Wilt disease using chemicals. However, many of these chemicals have been banned in Europe due to safety concerns, leading to a critical need for studies on pesticide-free control methods. During their evolution, plants have developed natural defences, such as systemic acquired resistance (SAR), against pathogens and pests. In this study, salicylic acid (10⁻³ M) was applied to MD2 and Queen Victoria pineapple plants as a foliar spray or soil drench, followed by mealybug infestation. This treatment enhanced defences, assessed through mealybug multiplication rates, and biochemical and molecular responses of tissue-cultured plantlets under controlled conditions. Phenylalanine ammonia-lyase activity (PAL) was measured as a potential SAR signalling enzymatic marker. Additionally, the expression levels of four genes were analyzed, which included AcPAL and AcICS2, both linked to salicylic acid synthesis; AcMYB-like, a transcription factor regulating salicylic acid biosynthesis; and AcCAT, which is involved in H2O2 level control in plants. SA elicitation reduced the mealybug multiplication rate by 70% on pineapples compared to untreated plants. In this study, the biochemical marker (PAL) and three molecular markers (AcPAL, AcICS2, and AcCAT) showed significant differences between primed and unprimed plants, indicating SAR induction and its role in the pineapple–mealybug interaction. In MD2 and Queen Victoria, PAL increased by 2.3 and 1.5, respectively, while AcPAL increased by 4 and more than 10. The other molecular markers, AcICS2, AcCAT, and AcMYB-like (a transcription factor), increased by 3, except for the last one in Queen Victoria. The reduction in mealybug populations with SAR is less effective than with pesticides, but it provides a valuable alternative on Réunion Island, where the only remaining insecticide will soon be banned. In addition, SAR priming offers a promising, eco-friendly strategy for managing mealybug populations and reducing Wilt disease in pesticide-free pineapple cropping systems.

Natural plant metabolites, also known as secondary metabolites, are crucial for the survival and adaptation of plants in their environment. For modern society, these metabolites can be produced under uncontrolled or controlled environments. Alkaloids, flavonoids, terpenoids, phenols, lignans, saponins, coumarins, and glucosinolates are among the most important natural products from plants. Proteases from pineapple cultures in temporary immersion bioreactors have been obtained. Additionally, the effects of sodium chloride, mannitol, and sodium azide on pineapple shoots propagated in temporary immersion bioreactors were recorded, with levels of chlorophylls, carotenoids, aldehydes, and phenolics measured. This short review summarizes the main results obtained.

Pineapple is a highly valuable tropical fruit crop with significant economic importance. In pineapple cultivation, several traits could benefit from genetic improvement, such as disease resistance, drought tolerance, fruit quality, shelf life, and yield. The methods used to genetically improve pineapple include traditional breeding, mutagenesis, biotechnology, genetic engineering, and in vitro culture. A few notable scientific groups worldwide performing pineapple genetic transformation include the South China Agricultural University, the Chinese Academy of Tropical Agricultural Sciences, the University of Hawaii, and Del Monte. The main transgenes introduced into the pineapple genome are the antisense ACC oxidase gene, herbicide resistance genes, carotenoid biosynthesis genes, and disease resistance genes. Our group at the Bioplant Centre, University of Ciego de Ávila, Cuba, also transformed pineapple and evaluated the field performance over more than 8 years. We compared transgenic ¨Cayena Lisa Serrana¨ cultivar plants to macropropagated controls, evaluating physiological and biochemical indicators of the phenotype. Out of 160 characters evaluated, significant differences were observed in 88 characters between the transgenic plants and the conventionally vegetative propagated plants, and in 70 characters between the transgenic plants and the micropropagated plants. Overall, the phenotype of the transformed material conforms to the phenotype of the two controls. These consistent data reflect the usefulness of characterizing the modified plants.

The objective of this work was to determine the effect of solar radiation intensity of the grazing system on sheep behavior. Treatment 1, consisted of monoculture of natural grasses (47 ± 5 lux), treatment 2 of natural grasses with Leucaena leucocephala trees (34 ± 3 lux) and treatment 3 of natural grasses with Manguifera indica trees (16 ± 3 lux). The total time of each activity per daily session was determined. A completely randomized design was used with a 3x2 factorial arrangement (three intensities of solar radiation, two sessions per day). Grazing behavior was affected by the interaction between factors. The grazing-walking activity was higher in the pastures with lower levels of solar radiation (Leucaena y Manguifera), with 217.50 y 216.38 min, respectively, in the morning session, while all times were lower in the afternoon session, with the lowest result in grazing in the sun (108.05 minutes). The reduction of solar radiation under the treetops favored the behavior of the sheep, which allowed the animals to perform resting and ruminating activities under the shade of the trees, more preferably in the afternoon session.

Despite the existence of effective therapy options for patients with localized colorectal cancer, advanced-stage patients have limited therapies. Genomic profiling is a promising tool for guiding treatment selection as well as patient monitoring. Here, we describe a novel gene rearrangement (CCDC6::CASP7) detected in a patient with advanced colorectal cancer that could be a therapeutic target. The patient underwent surgical resection but died after the operation from fecal peritonitis. To our knowledge, this is the first report in which the CCDC6::CASP7 gene rearrangement has been described in an advanced colorectal adenocarcinoma patient.

The main objective of this work was to develop a viewer with web output, through which the changes experienced by the mangroves of the Gran Humedal del Norte de Ciego de Avila (GHNCA) can be evaluated from remote sensors, contributing to the understanding of the spatiotemporal variability of their vegetative dynamics. The achievement of this objective is supported by the use of open-source technologies such as MapStore, GeoServer and Django, as well as Google Earth Engine, which combine to offer a robust and technologically independent solution to the problem. In this context, it was decided to adopt an action model aimed at automating the workflow steps related to data preprocessing, downloading, and publishing. A visualizer with web output (Geospatial System for Monitoring Mangrove Ecosystems or SIGMEM) is developed for the first time, evaluating changes in an area of central Cuba from different vegetation indices. The evaluation of the machine learning classifiers Random Forest and Naive Bayes for the automated mapping of mangroves highlighted the ability of Random Forest to discriminate between areas occupied by mangroves and other coverages with an Overall Accuracy (OA) of 94.11%, surpassing the 89.85% of Naive Bayes. The estimated net change based on the year 2020 of the areas determined during the classification process showed a decrease of 5138.17 ha in the year 2023 and 2831.76 ha in the year 2022. This tool will be fundamental for researchers, decision makers, and students, contributing to new research proposals and sustainable management of mangroves in Cuba and the Caribbean.

Small-sized invertebrates inhabiting hard substrates in coral reefs (a.k.a. cryptofauna) contribute substantially to reef biodiversity, but their patterns of distribution and ecological controls are poorly understood. Here, we characterized the cryptofauna community and explored “bottom-up” and “top-down” controls by benthic cover and fish abundance, respectively. We sampled the cryptofauna inhabiting the reef terrace from 13 sites along 200 km in Jardines de la Reina (Cuba), a well-preserved and protected area in the Caribbean. We counted 23,959 invertebrates of 14 higher taxa, being the most abundant Copepoda (54%), Nematoda (21%), Mollusca (7%), Ostracoda (5%), Polychaeta (5%), and Amphipoda (3%). Richness, abundance, and community structure varied across the reefs without any geographical gradient of distribution. One-third of the variance occurred at site scale (~ 10 km), and half occurred at quadrat scale (~ 1 m). Algal cover promoted cryptofauna richness and abundance likely providing substrate and food, while live coral cover negatively influenced nematode abundances, potentially due to coral defenses. Relationships between cryptofauna and reef fishes were also present, with invertivores and herbivores negatively affecting cryptofauna abundance likely due to direct or indirect predation pressures. This research highlights the important roles of bottom-up and top-down controls, by algal/coral cover and fishes, respectively, on cryptofauna and in extension to coral reef biodiversity. Current threats by climate change are expected to alter these controls on cryptofauna resulting in changes to diversity, trophodynamics and energy flows of coral reefs.

El presente artículo científico trata sobre la práctica educativa de la preparación teórica en el entrenador de béisbol, la misma es un tema que aún tiene un largo camino que recorrer en las ciencias de la educación, y este aspecto se hace importante concretarlo desde las propias prácticas educativas atendiendo a las características de las especialidades deportivas, ya que las concepciones expuestas en la actualidad, según criterios autorales se enfocan en diferentes orientaciones, de forma general, aislada e integrada; siendo esta última de gran importancia su definición desde la práctica educativa actual del entrenador de béisbol, en la búsqueda de que el atleta aprenda no solo a pensar, sino también actuar, predecir y resolver aspectos de su preparación implícitos en el programa de entrenamiento. Lo abordado en esta investigación busca resaltar la importancia de la integración de la preparación teórica con las demás preparaciones del entrenamiento deportivo en el béisbol. Se plantea como objetivo: argumentar los elementos esenciales que comprende la práctica educativa de la preparación teórica del entrenador de beisbol. Los métodos científicos empleados para ello son el analítico – sintético, entrevista y la revisión documental que se permitió declarar el problema científico y darle solución al mismo.

This paper discusses the mechanisms by which fungi manipulate plant physiology and suppress plant defense responses by producing effectors that can target various host proteins. Effector-triggered immunity and effector-triggered susceptibility are pivotal elements in the complex molecular dialogue underlying plant–pathogen interactions. Pathogen-produced effector molecules possess the ability to mimic pathogen-associated molecular patterns or hinder the binding of pattern recognition receptors. Effectors can directly target nucleotide-binding domain, leucine-rich repeat receptors, or manipulate downstream signaling components to suppress plant defense. Interactions between these effectors and receptor-like kinases in host plants are critical in this process. Biotrophic fungi adeptly exploit the signaling networks of key plant hormones, including salicylic acid, jasmonic acid, abscisic acid, and ethylene, to establish a compatible interaction with their plant hosts. Overall, the paper highlights the importance of understanding the complex interplay between plant defense mechanisms and fungal effectors to develop effective strategies for plant disease management.

Cryopreservation remains the technology of choice for the long-term preservation of plant germplasm. The current contribution reports on the response of seeds of N. wightii, P. vulgaris and T. indica to cryopreservation in terms of plantlet survival post cryostorage as well as examination of the external morphology of seed coats using scanning electron microscopy (SEM). Survival was determined in Petri dishes in the laboratory as well as in the soil. The results showed differential responses in seeds of the three tested species. In the case of P. vulgaris, exposure to liquid nitrogen (LN) did not adversely affect seedling emergence or characteristics of the seed coat. For N. wightii and T. indica, cracks in the seed coat that were apparent in control seeds, appeared more frequently following exposure to LN. In the case of the former species, this observation did not yield adverse consequences and seed germination rate did actually increase from 5.8 to 85.9% after LN treatment. However, in the case of T. indica, the initial growth rate of seedlings was delayed relative to the control although the germination rate was improved. It is postulated that seeds of T. indica possibly incurred additional damage to other seed components which might have led to delayed recovery.

Islands are biodiversity hotspots yet accelerated levels of land degradation as a consequence of infrastructure development is posing a serious threat to native species. Cuba contains the largest diversity of cacti in the Caribbean, however, some are critically endangered such as those within the genus Consolea. Therefore, the present study undertook a census of Consolea millspaughii subsp. millspaughii on the Cayo Paredón Grande in Cuba to assess the current status of populations. A secondary goal of the study was to develop the preliminary stages for a micropropagation protocol for this species. The results showed a worrying decline in adult cacti from the last census conducted in 2019 (a reduction from 15 to 5 adult plants). However, up to 41 juvenile plants were noted which is encouraging from a conservation perspective. The early stages of the micropropagation protocol were established with NaClO being sufficient to remove surface decontaminants. Up to 100% sprouting was obtained on medium supplemented with 4.43 µmol L−1 benzyladenine and 66.7% rooting was obtained on medium devoid of plant growth regulators. Future studies will involve refinement of the micropropagation protocol so that plants can be multiplied for restoration efforts to support conservation of this endangered species.

Cuba annually exports pineapple as fresh fruit to European markets, however, the tropical conditions in which pineapple cultivation takes place cause burns on the fruit, mainly in the summer months (June-August). Sunburn damage causes economic losses by subtracting the commercial value of fresh fruit. In this work, the phenomenon of sunburn in pineapple fruits (Ananas comosus var. comosus) of the ‘MD-2’ hybrid was characterized through a morphological, physiological and biochemical study of the fruits produced in the months with the highest incidence of this problem. The degree of burns on the fruits was evaluated at 90, 120 and 150 days after floral induction (DAFI). The exterior and interior temperature of the fruits in the east and west sides of orchard was evaluated during 9 h (8:00–17:00). Additionally, morpho-physiological and biochemical variables of the fruits were evaluated during their development. The temperatures on the surface of the fruits fluctuate between 45 and 50ºC, being higher on the west side where they exceed 42ºC inside. Sunburn on the fruits only appears during the last month of development and with a higher incidence on the west side. This increase in burns coincides with the time of physiological maturity of the fruits and the decrease in chlorophyll concentration and a marked increase in antioxidant enzymatic activity in response to the stress that the fruits face