Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

The use of plant waste is a topic of current interest due to the environmental effects it causes on the environment. The waste from the leaves of Arazá (Eugenia stipitata Mc Vaugh) is not used in Ecuador and in the Amazonian Experimental Research and Production Center, located in the canton of Santa Clara, province of Pastaza, a significant amount of waste is obtained from this type of crop. , therefore the objective of the study was to determine the chemical composition of its essential oil, using three extraction methods, to evaluate the effectiveness of these methods in terms of performance and establish their possible applications in the agroindustrial area. Three methods were used to extract the essential oil: steam drag, maceration and ultrasound-assisted extraction; To determine the chemical components, gas chromatography coupled to mass  spectrometry was used. The results determined that ultrasound-assisted extraction turned out to be more efficient, with a yield of 2.17%, Phenols (47.75%), Hydrocarbons (35.51%), Acids and Esters (6.10%) were identified as major components; In steam distillation, although less efficient in terms of 0.01% yield, Terpenes (57.57%), Alcohols and Other Compounds (36.57%), Sesquiterpenes (5.85%) were identified; and in the case of maceration it gave a 1.5% yield, Phenols (75.84%), Esters and Acids (12.91%) and Amides (6.17%) were identified. This rich composition of bioactive components highlights its importance as waste due to its applications in the food, pharmaceutical, cosmetic and phytosanitary industries.

This study focused on evaluating the agronomic and productive response of sweet potato (Ipomoea batatas) variety INIAP-Toquecita to the application of various soil bioinputs. The study took place at INIAP’s Portoviejo Experimental Station in Ecuador, from July to December 2022. The effects of several bioinputs, including diatoms, efficient microorganisms, biochar, earthworm humus, and organic matter, on various agronomic parameters were analyzed. The findings revealed statistically significant effects of these bioinputs on variables such as rooting rate, foliage cover, root biomass, root proliferation, aboveground biomass yield, commercial tuberous root production, leaf chlorophyll content, and nutrient concentrations in both soil and plant tissue. Biochar proved particularly effective in promoting vegetative growth, increasing vine proliferation per plant (9 vs. 6 vines·plant-1 in other treatments) and aboveground biomass production (24.17 t·ha-1). Vermicompost achieved the best initial establishment (100%) and the highest yield of commercial tuberous roots (24.90 t·ha-1). The addition of plant residues generated the highest concentration of foliar chlorophyll (range 41.86-45.93). At the end of the cycle, all treatments maintained adequate nutritional status, with significant absorption of phosphorus and iron. The results suggest that these bioinputs are an effective alternative to conventional chemical fertilization in sweet potato cultivation, with specific benefits for each, depending on the production objective.

In order to evaluate the primary morphometric variables, of branches and leaves per plant, in moringa, an experiment was set up at the “Guachimarí” farm, Maturín municipality, Monagas state, Venezuela. A nursery was created to produce seedlings, which were later transplanted to the field. A randomized block design was used, with five treatments or planting densities (16,000; 20,000; 26,666; 40,000 and 80,000 plants.ha-1), four repetitions and experimental units of 9 m2. The harvest was carried out 215 days after transplantation. Prior to this, the primary aerial morphometry was determined: plant height (PH), basal stem diameter, number of branches and the robustness index RI); after this, the branch morphometric variables were quantified: length, diameter, number of leaves and height to the first branch (HFB); and in the leaf: length and width. The values were studied using the ANOVA procedure, descriptive statistics, regression analysis and correlations. Planting density did not affect (P>0.05) most of the foliage morphometric variables, except for RI and HFB, with coinciding maxima, close to the critical density of 50,000 plants·ha-1, and influenced by physical limitations of the soil. In morphometric correlations, the variable PH was positively associated with variables measured in branch and leaf (r= 0.71**); in contrast, there was a negative association between the number of branches·plant-1 and the number of leaves·branch-1 (r= -0.74**). Genetic and physiological aspects of the crop are involved, especially the habit of vertical growth at high rates.

Multitemporal analysis allows to discover changes between different reference dates, following the evolution of the natural environment and the consequences of human action on it. The purpose of the study was to carry out a multitemporal analysis of land use change in the Tosagua Canton in the period 2017-2023, through satellite images, in order to know the state of fragmentation of the vegetation cover. The changes in land use of the canton were obtained, resulting in a total change rate of 9% in 6 years. Using the supervised classification, it was possible to generate thematic maps with four classes of land use where field verification was carried out to identify land cover and it was established that for the period 2017-2019, the vegetation and agricultural land cover was 13,956.60 ha with 19,430.86 ha of vegetation cover. For 2019-2021, a vegetation cover of 10,280.03 ha and 23,980.97 ha of agricultural land was recorded and for 2021-2023 the vegetation cover area was 10,120.01 ha with 24,1134.07 ha of agricultural land. The rate of change in the use of cover was observed with a decrease of 14% during the years 2017 and 2019, while for the years 2021 and 2023 a notable recovery of the vegetation cover is observed with 6%. In addition, an overall reliability of the actual and inferred coverage of 83.8% was achieved, which indicates that the classification of land uses in the Tosagua canton is admissible.

Approximately 35% of all food produced depends on biological pollination and 90% of this pollination involves Apis mellifera. This species is vital for agricultural pollination, but faces threats such as pests, diseases and climate change that have increased colony mortality. The objective of the work was to carry out a sanitary assessment of A. mellifera in the province of Pastaza. The methodological approach was observational and descriptive using stratified sampling in active hives to evaluate the presence of diseases such as american and european foulbrood, and the Varroa destructor mite. For V. destructor, the “jar test” and bacteriological cultures for the foulbrood were used. The results revealed that no cases of american or european foulbrood were detected in the hives, showing that environmental conditions in Pastaza could be less favorable for these pathogens. However, the prevalence of V. destructor was significant, affecting 34.21% of the evaluated hives, with some exceeding the critical threshold of 5% infestation, which represents a considerable risk to the health of the colonies. These results show the urgent need to implement integrated beekeeping management strategies to control V. destructor infestation and prevent colony collapse. In conclusion, the absence of foulbrood is a positive finding, and the high prevalence of V. destructor shows the importance of improving beekeeping management practices in Pastaza to ensure the long-term sustainability of beekeeping in the region.

Cadmium (Cd) contamination in maize is crucial for ensuring food security,as this heavy metal can accumulate in the grains and pose a significant risk tohuman health. The objective of this research was to evaluate calcium (Ca) sources and organic matter (OM) as alternatives to reduce cadmium uptake in maize. A completely randomized design with a 2 x 4 factorial arrangement was used, wheredifferent treatments combining OM application and Ca sources were evaluated. Soil preparation included the addition of compost in the OM treatments. Cd contamination was induced by adding cadmium chloride (CdCl₂), followed by the application of Ca sources through irrigation. Maize seeds were planted in pots with consistent irrigation to maintain adequate moisture. Over a period of60 days, various variables were monitored and recorded, including dry weight and Cd concentration in roots and stems. The results showed highly significant differences in the dry biomass of maize leaves and roots exposed to cadmium contamination, both in simple effects and in the interaction between OM and Casources. It was observed that the incorporation of 2% OM and calcium nitrate Ca(NO₃)₂ had a significant impact on biomass production and Cd concentration in maize plants exposed to the contaminant, both independently and in combination.

Louise von Panhuys (1763–1844) and Nancy Anne Kingsbury Wollstonecraft (1791–1828) stand out historically as the first female illustrators of neotropical orchids. Louise von Panhuys epitomized an era when high social status equated to a refined education; as the writers of her time described, a classic “lady of leisure.” In contrast Nancy K. Wollstonecraft, was the daughter of a clergyman from New England, born into the broad American middle class which shaped the early decades of the United States’ independent life. Both shared a common passion for: the exuberant forests of the Caribbean European colonies: von Panhuys in the Dutch territory of Suriname and Wollstonecraft in the Spanish island of Cuba. The artistic result of these two women’s works is astounding and went in different directions: while von Panhuys painted to entertain herself and with a mostly descriptive purpose, Wollstonecraft combined her artistic talent and her botanical knowledge into a three-volume manuscript, Specimens of the Fruits and Plants of the Island of Cuba (unfortunately never published), with accurate and detailed descriptions and beautiful illustrations. Biographies of these two extraordinary women are accompanied by complete sets of their orchid paintings, eight by Panhuys (along with several of her landscapes and scenes from Suriname) and nine by Wollstonecraft. A clarifying note: Wollstonecraft’s name is indistinctly given as ‘Nancy Anne’, ‘Anne’, or ‘Nancy’. The author has adhered to the name as given in the different bibliographical sources.

A new species of Pleurothallis subgenus Talpinaria, discovered in the department of Tolima, Central Andes of Colombia, is described, illustrated, and discussed. The new species, Pleurothallis vallejoi is compared with P. talpinaria from Colombia and Venezuela, P. trimeroglossa from Peru and Ecuador, P. jostii, presumed to occur in Ecuador, and P. gracilicolumna from Colombia. The new species is distinguished from the previous ones by a lip with subquadrate lateral lobes, with narrowly elliptical basal auricles, and a callus that is elongated, thin, and slightly elevated, with the median lobe occupying almost half of the total lip length. Additionally, the pollination mechanism of the P. talpinaria complex is described and discussed.

On March 26, 1863, Charles Darwin wrote a letter to Joseph Dalton Hooker, describing his attempts to germinate orchid seeds. In this letter, he mentioned his hope to observe orchid seedlings and expressed a “notion that [the seeds]. . . are parasites in early youth on cryptogams!!”. This statement appears to predict Noël Bernard’s 1899 discovery that orchid seeds require fungal colonization for successful germination. However, there is some uncertainty regarding Darwin’s exact meaning. The term “cryptogams” in his time commonly included fungi but also encompassed bryophytes, pteridophytes, and other non-vascular plants. Since Darwin mentioned sphagnum in his experiments, it is possible to suggest that he may have considered mosses as potential hosts rather than fungi. But, since this was a personal letter to Joseph D. Hooker rather than a formal publication, Darwin may have been less precise in his terminology. Nevertheless, considering Darwin’s broader interest in plant-fungal interactions, it is very plausible that he regarded fungi as possible symbiotic partners in orchid germination. The extent of Darwin’s prescience on the orchid-fungal relationship may be debatable terminologically (did he mean fungi by using “cryptogams”?). However, his speculation was remarkably intuitive, questioning whether orchids required an external biological partner for germination. Darwin’s letter demonstrates his foresight, but it does not diminish Noël Bernard’s monumental achievement. Bernard made his discovery independently, without knowledge of Darwin’s observations, relying solely on his extraordinary scientific talent. His work remains a cornerstone of orchid science. Unfortunately, Darwin’s prescient letter seems not to have been noticed, appreciated, or cited often enough in the orchid literature during its 162 years of existence.

The first naturalization of the orchid Cymbidium aloifolium in the world is reported in a residential neighborhood in southern Florida near Miami. A survey for naturalized plants of this epiphytic orchid, which is native to South and Southeast Asia, found 101 plants growing on 38 different trees belonging to 13 different species. Of these 101 plants, 53 were mature, capable of reproduction, 37 were juveniles, and 11 were seedlings. Seven plants bore a total of 86 fruit. The tree hosts with the most plants were the palms Phoenix roebelenii and Thrinax radiata, and a mahogany (Swietenia macrophylla). A small remnant of the Pine Rockland within this residential area had three native tree species with four plants of this orchid, indicating the potential of the orchid to invade this unique, rare plant community. Cymbidium aloifolium’s occurrence at higher latitudes and altitudes in its native Asia than where it has naturalized in Florida suggests that it should be able to live farther north in Florida.