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Cannabis is an herbaceous species of the Cannabaceae family and is native to the Himalayas. It contains hundreds of metabolites with potential bioactivity, including cannabinoids, terpenes, and flavonoids. The objective of this experiment was to evaluate the yield and the cannabidiol (CBD) and tetrahydrocannabinol (THC) content of medicinal cannabis (variety Cherry Oregon) in two localities of the Ecuadorian highlands. A Randomized Complete Block Design with four treatments and four replications was carried out. Treatment 1 was maintained with natural light, treatment 2 received 16/8 photoperiod (16 hours light, 8 hours dark) for one week, treatment 3 received 16/8 photoperiod for two weeks, and treatment 4 received 16/8 photoperiod for 3 weeks. In the locality 1, treatment 4 showed better values of plant height, dry biomass, biomass yield per plant and greater biomass yield per m2, in both cycles. In the locality 2, the treatments were statistically similar in all variables in both cycles, but a trend where treatment 4 presented higher values compared to the rest of the treatments was observed. The THC and CBD contents for the treatments and cycles ranged between 0.06% and 0.51%, and between 13.76% and 15.29% respectively in both localities. Finally, the results obtained agree with what is reported in the variety's technical sheet, and the THC content does not exceed the maximum value allowed by Ecuadorian regulations.

Agroforestry systems (AFSs) seek synergies that improve productivity, sustainability, and environmental benefits. This is achieved through the supplying of nutrients to the soil, carbon storage, and sequestration. In the Ecuadorian Amazon, Coffea canephora is planted together with leguminous, woody, forest, and secondary forest species, where the continuous incorporation of vegetative residues from shade species represents a substantial addition of nutrients within these systems. This study was carried out from 2018 to 2022 to determine the contribution of nutrients contained in the biomass and C sequestration in agroforestry systems of coffee with conventional (high use of agrochemicals) and organic (without the use of chemicals) management. The study was carried out with a randomized complete block design, using a factorial arrangement (2 × 4 with three replications). This arrangement included two types of systems (agroforestry and monoculture) and four agronomic management practices (high and medium for conventional, and intensive and low organic). The biomass and nutrient content were measured twice a year (every 180 days); in addition, the yield was also recorded. A multivariate and univariate analysis was used for data analysis through R and SAS software. After five years of evaluation, it was determined that the N, K, Ca, and Mg contents were higher in the agroforestry systems than the monocultures. In the AFSs, the highest nutrient content was obtained with the medium conventional and low organic agronomic management, while in the monocultures, it was obtained with the high and medium conventional management. In addition, at a soil depth of 20 cm, the total storage and CO2 were 38.12 and 139.8 t ha−1, respectively. The highest yields were obtained with conventional management in AFSs (1599 kg ha−1) and monoculture (1789.45 kg ha−1). Overall, AFSs showed a significant contribution of nutrients, such as N, K, Ca, and Mg, for coffee cultivation; moreover, yields were similar in the AFS and monoculture with both conventional and organic management, which is positive, since AFSs also contribute environmental benefits.

ABSTRACT “Purple top” is an emerging disease that affects solanaceous crops, reported mainly on Solanum tuberosum (potato). Additionally, Bactericera cockerelli has been reported as the insect vector of Candidatus Liberibacter solanacearum (CaLso), a pathogen that has been associated with this disease. However, the information about this disease in Andean fruit species such as Solanum betaceum (tree tomato), S. quitoense (naranjilla) and Physalis peruviana (cape gooseberry) is almost nil. This study was carried out in the Tumbaco Experimental Farm of INIAP to describe the phenotypic symptoms caused by this disease. Molecular diagnosis by PCR method was carried out to diagnose the causal agent associated with the symptomatology. The main symptoms observed were purple color leaves, smaller apical leaves, inward curvature edge leaves, over-sprouting, yellowish and stopped plant growth; however there also were asymptomatic plants. P. peruviana was the most susceptible species because showed 100% of incidence. CaLso was identified as the causal agent associated with this disease. These results contribute to understanding the expression of this disease in Andean fruit crops. However, more studies related to epidemiology, diagnostic methods, mixed infections, vector-pathogen interaction and disease control are required in order to generate information that allows a complete knowledge of this pest.

Agroforestry systems in the Ecuadorian Amazon play a vital role in environmental conservation and the promotion of sustainable agriculture. Therefore, it is crucial to demonstrate the benefits of the associated species within these production systems. This study aimed to assess the impact of agroforestry systems on cocoa yield, carbon sequestration, earthworm presence, and the nutritional contribution of companion species linked to cocoa (Theobroma cacao L.) cultivation under agroforestry systems. The research was conducted at INIAP’s Central Experimental Station of the Amazon using a randomized complete block design with three replications. The agroforestry arrangements were: (1) monoculture; (2) forest (Cedrelinga cateniformis Ducke); (3) fruit forest (Bactris gasipaes Kunth); (4) service (Erythrina poeppigiana (Walp.) O.F.Cook); and (5) forest + service (E. poeppigiana + C. cateniformis). The results indicated that agroforestry systems showed better results than the monoculture in terms of yield (532.0 kg ha−1 compared to 435.4 kg ha−1) and total stored carbon (33.0–42.0 t ha−1 compared to 39.6 t ha−1). Additionally, agroforestry systems provided higher levels of Mg, B, and Ca, contributing to both crop yield and the presence of earthworms. These findings suggest a positive influence of companion species, improving soil nutrition through biomass incorporation and promoting environmental benefits (carbon sequestration). Therefore, agroforestry systems will support sustainable cocoa production in the Ecuadorian Amazon.

Se aplicaron consorcios microbianos en un sistema de producción de plántulas de aguacate (Persea americana Mill.) cultivar ‘Criollo’, evaluándose posibles influencias en el crecimiento y estado nutricional de los patrones. Se evaluaron 4 tratamientos en un diseño de bloques completamente al azar (DBCA). Las semillas utilizadas fueron sembradas en sustrato estéril (tierra negra y pomina; 3:1) colocado en bolsas de vivero (polietileno, capacidad: 2,2 kg). Las inoculaciones de microrganismos (Glomus spp, Trichoderma spp., Bacillusspp., Pseudomonasspp.) se realizaron a los 70, 100, 120 y 150 días después de la siembra (DDS). Las variables altura de planta, diámetro de tallo eíndice de verdorfueron evaluadas a lo largo del ensayo (80, 110, 140 y 170 DDS); una vez culminado el ensayo (170 DDS) se evaluóla concentración de nutrientes en tejido, materia seca de tallos, hojas y raíces. Existierondiferencias estadísticamente significativas a los 170 DDS para:altura de planta, diámetro de tallo y contenido de clorofila; el análisis de concentración de nutrientes en tejido reportó valores dentro de los parámetros adecuados para la especie eincremento en la concentración del Cu. Esta investigación reporta el efecto favorable de los microorganismos evaluados en el crecimiento de las plántulasy en laasimilación de nutrientes.

Maize (Zea maysL.) germplasm from the Ecuadorian Higlands has low tolerance to inbreeding especially in starchy cultivars. To create competitive varieties at the commercial level it is necessary to identify outstanding progenitor lines by early testing. The purpose of this research was to evaluate the yield potential of S1linesof black corn by early testing. The experiment was conducted at the “Tunshi” Experiment Station, Licto parish, Chimborazo province, Ecuador using a complete random block design with four replications. Twenty-four treatments were evaluated, each consisting of an S1line of black corn. Agronomic traits were registered and the percentage of inbreeding depression was calculated. The lines presented statistical differences (P ≤ 0.05) in the variables days to male and female flowering, plant height, ear height, leaf disease, ear length, weight of 100 kernels and grain yield. All the variables showed inbreeding depression, except days to male flowering, which presented a low increase. Lines 16, 15 and 22 were the most productive with yields of 2.00; 2.08 and 1.95 t ha-1respectively. These resultsallow to select lines with less depressive effects on yield produced by inbreeding, and to continue with the improvement processes of black maize.

Tree tomato (Solanum betaceum) is susceptible to nematode attack; for this reason, grafting is used as an alternative to reduce this impact. In this study, the bioactive compounds of the fruit (shell, pulp, and seed jelly) of two tree tomato ecotypes (‘giant orange’ and ‘giant purple’) were evaluated in both control and grafted plants grown at different altitudes (2010–2250, 2260–2500, 2510–2750 and 2760–3000 masl). Commercial quality, vitamin C, organic acids, phenolics, carotenoids and antioxidant activity were determined by microextraction and quantified by liquid chromatography (RRLC) or spectrophotometry (microplate reader). The results showed high concentrations of vitamin C, organic acids and antioxidant activity in the seed jelly, organic acids in the pulp and phenolic compounds, carotenoids, and antioxidant activity in the shell. The main phenolics were ferulic acid, caffeic acid and luteolin, while the main carotenoids were lutein, B-cryptoxanthin and B-carotene. Multivariate analysis showed that tree tomato quality was mainly influenced by altitude and fruit part and that grafting positively affected soluble solids for both ecotypes and all altitudes.

Avocado demand has increased in recent years due to the nutraceutical properties that this fruit has and its positive impacts on human health; however, avocado production also requires sustainable alternatives to improve its cultivation. The objective of this study was to carry out characterization of the mineral content and phytochemical compounds in avocado fruit of the Hass variety grown using sustainable agricultural practices in Ecuador. Our results show an increase in fruit quality traits, such as firmness, and in the content of soluble solids, protein, fiber, fat, carotenoids, Ca, Mg, Zn and stearic acid in the pulp of the avocado Hass variety, as well as an initial trend of yield increase with the application of sustainable practices. Moreover, antioxidant activity was associated with polyphenol content. There were positive correlations of Mg with K and Ca, and of flavonoids with linolelaidic, linoleic and linolenic acids. Overall, our results indicate that avocado can be used as a functional and nutritional food due to its phytochemical composition and the mineral content of its pulp, which contributes to the promotion of its consumption and encourages healthy eating. In addition, the use of sustainable practices, such as fertigation and the application of microorganisms, is also promoted for growing avocado.

The infestation of the root system by nematodes (Meloidogyne incognita) and Fusarium solani to the rootneck hinders the production of tree tomato (Solanum betaceum Cav.), an Andean native fruit consumed in Ecuador and other countries. This paper evaluates the potential of different Ecuadorian Andean Solanaceae species (Solanum auriculatum, Solanum asperolanatum, Solanum arboreum and Nicotiana glauca), such as tree tomato rootstocks towards Fusarium and nematode resistance through controlled inoculation trials. The experimental design used was complete randomized in factorial arrangement with three factors. The variables were: fungus incubation time, incidence and lesion size, increase in nematode population, plant height increase and plant fresh weight. The most promising results for an extended open field evaluation were N. glauca (no incidences of Fusarium and 0.36 times increase in nematode population), followed by S. auriculatum. Fruit of these plants were assessed for chaconine and solanine content. The results indicated that the two rootstocks did not induce toxic substances in the fruits, they are suitable for commercial production zones, enhance crop yield, increase productive plant life and use fewer chemicals to control soil pathogens.

The province of Tungurahua is well known for the production of deciduous fruit trees in Ecuador, however, its production is impacted by some issues that affect productivity. The purpose of this investigation was to conduct a diagnosis of the production system of deciduous fruit trees in 6 locations in Tungurahua province. Surveys were carried out to obtain information on 117 production units (farms). A regression model was used to determine the relationship between the variables and their incidence in the production system. The results showed that peach (Prunus persica) is the fruit crop with highest yield (16.19 t ha-1), followed by apple (Malus domestica) (13.36 t ha-1) and pear (Pyrus communis) (13.15 t ha-1). Apple cultivars Emilia and Golden Delicious, cv. Uvilla of pear and Conservero Amarillo of peach were the most cultivated in Tungurahua. The main factors that influenced the farmer income were: Land area used for cultivation, reason for growing fruit trees, age of the producer, fruit selection and type of production. It is necessary to advocate to expand the cultivated land area of these fruit crops in order to satisfy local demand and compete with imports of these fruits.

En la actualidad el cultivo de la granadilla ha tomado importancia en la zona norte del Ecuador; sin embargo, la información en el manejo nutricional de este frutal es escasa, ocasionando problemas como bajos rendimientos y calidad de la fruta. Debido a la alta demanda de nitrógeno y potasio de este cultivo, el objetivo de esta investigación fue evaluar el efecto de dos niveles de estos nutrientes en la fase de crecimiento. Se utilizaron plantas de granadilla cultivar “Colombiana”, los tratamientos se aplicaron mediante fertirrigación. El experimento se desarrolló en la Granja Experimental Tumbaco del Instituto Nacional de Investigaciones Agropecuarias (INIAP), bajo un diseño completamente al azar (DCA) en arreglo factorial 2 por 2, teniendo cuatro tratamientos resultado de la interacción de los niveles de nitrógeno y potasio. Los resultados obtenidos mostraron que las dosis altas de nitrógeno y potasio (200 kg ha-1) y su interacción tuvieron los valores más altos en las variables: altura de planta (1,74 m), índice de verdor (59,07 SPAD), área foliar (151,03 cm2) y concentración foliar de nutrientes (4,13% N y 4,10 %K).

Agroforestry systems allow conservation of natural resources and promotion of sustainable agriculture in the Ecuadorian Amazon. Nevertheless, the benefit of the associated species that are part of these production systems needs to be demonstrated. The aim of this study was to find out the influence on the crop yield, carbon sequestration, presence of earthworms, and the nutritional contribution of legume species associated with the naranjilla (Solanum quitoense) crop in an agroforestry system. The research was carried out in the Palora Experimental Farm of INIAP, using a randomized complete block design with three replications. The treatments were made up of cultivation systems (agroforestry systems with or without 50% fertilization) and monoculture as a control, with two levels of conventional fertilization (50 and 100%). In the agroforestry arrangements, Gliricidia sepium and Flemingia macrophylla were used to supply biomass. The results showed that during the three evaluation cycles, the yield of naranjilla was influenced by the quality of the biomass added to the soil and not by the amount of synthetic chemical fertilizer that was supplied. The biomass of G. sepium and F. macrophylla provided a greater amount of Mg, Mn, Zn, B, and Fe; elements that contributed to crop yield and the presence of earthworms. The results suggest that the use of legume species in agroforestry systems positively influenced naranjillla productivity, favoring sustainable agriculture in the Ecuadorian Amazon.

Seed is a fundamental tool to carry out breeding processes and for the propagation of the crops; however, seed propagation generally has low and irregular germination. Passion fruit (Passiflora) species are economically important for Ecuador, which is the main exporter of passion fruit concentrate in Latin America. Ecuadorian farmers propagate new plants by seeds to establish new passion fruit orchards or to extend their cultivated area. The objective of this research was to determine the differences in germination and seedling development with the application of priming methods in five genotypes of passion fruit belonging to three different taxa that are of commercial use in Ecuador. The genotypes used were: INIAP 2009 and P10 (P. edulis f. flavicarpa), Gulupa (P. edulis f. edulis), and local germplasms POR1 (P. edulis f. flavicarpa) and PICH1 (P. maliformis). The priming methods were: water (control), hydrogen peroxide at 15%, potassium nitrate at 1%, PEG 6000 at −1.2 MPa, and gibberellic acid at 500 ppm. The results showed that there was a genotype-response depending on the priming method. Nevertheless, Polietilenoglicol (PEG 6000) could be considered as a promising method to encourage seed germination and promote seedling growth in the Passiflora species. More research regarding the use of this compound has to be carried out in order to determine in depth the physiological processes related to its functions to improve seed germination as well as production of vigorous seedlings.

Babaco is a fast-growing herbaceous shrub with great commercial potential because of the organoleptic properties of its fruit. Babaco mosaic virus (BabMV) is a potexvirus in the family Alphaflexiviridae affecting babaco in all the provinces that produce this crop in Ecuador. BabMV was recently described but it has been affecting babaco for decades and, since many potexviruses are serologically indistinguishable, it may have been previously misidentified as papaya mosaic virus. Based on the coat protein (CP) gene, we aimed to study the distribution and epidemiological patterns of BabMV in babaco and chamburo over the years and to model its three-dimensional structure. Sequences of the CP were obtained from thirty-six isolates from plants collected in the main babaco-producing provinces of Ecuador between 2016 and 2021. The evolution rate of BabMV was estimated at 1.21 × 10−3 nucleotide substitutions site−1 year−1 and a time of origin of the most recent common ancestor around 1958.80. From molecular dynamics simulations, compared to other proteins of BabMV—RDRP, TGB1, and Alkb domain—the CP exhibited a higher flexibility with the C and N terminals as the most flexible regions. The reconstructed viral distribution provides dispersion patterns which have implications for control approaches of BabMV.

La producción científica en Ecuador ha seguido un patrón similar a la evolución de otros países latinoamericanos, existiendo escasa generación de documentos indexados; pero en los últimos años se ha incrementado. El INIAP ha plasmado los resultados de sus investigaciones en publicaciones técnicas, dípticos, guías, manuales, entre otros. Desde el año 2014 ha tenido un aumento sostenido en su producción científica, debido a nueva reglamentación de acreditación e incentivos a investigadores. El objetivo de la presente investigación fue realizar un análisis de la producción científica del INIAP durante el periodo 2014-2019. Los resultados mostraron un aumentó 3,1 veces durante el periodo analizado, superando el crecimiento latinoamericano en ese mismo tiempo. Se determinó que más del 54% de las publicaciones del INIAP tienen colaboración internacional y el 62% de publicaciones están indexadas en revistas con índice SJR. Estos resultados indican que INIAP ha incrementado su producción y calidad científica en investigación agropecuaria.

There are several species of passion fruit grown in South America. However, there is a lack of information about the mineral content in their pulp. Thus, the objective of the present research was to determine the mineral content in the pulp of different germplasms of passion fruit [Passiflora edulis f. flavicarpa (INIAP 2009 and P10), P. alata (Sweet passion fruit), P. edulis f. edulis (Gulupa) and Passiflora sp. (Criollo POR1 and Criollo PICH1)] grown in Ecuador and to determine their relationship with relevant fruit quality traits. The results showed that high Mg content was associated with less peel thickness, soluble solids was negatively related to K and B content, and vitamin C was negatively related to S content. INIAP 2009 had high titratable acidity and fruit weight but low N and Na; P10 showed the highest contents of N, K, Na, Mn and fruit weight but less P, Mg, and Fe; sweet passion fruit showed high S, Zn, Cu, soluble solids, and peel thickness but low K, Ca, B, and titratable acidity; Gulupa had high Mg, B, and Zn but low S, Fe, and Mn; Criollo POR1 showed high N and Fe but low Zn; and Criollo PICH1 showed high P, Ca, Mg, and Cu but low soluble solids and peel thickness. These results provide additional information on passion fruit germplasm grown in Ecuador and constitutes a reference for further breeding programs.

El cultivo de la uva (Vitis vinífera L.) está incrementándose en el trópico seco y los valles interandinos del Ecuador. Sin embargo, la calidad del racimo y las bayas del cv. ‘Marroo Seedless’ cultivado en los Valles requieren mejorarse para competir con la fruta importada. Para ello, en plantas de 8 años se realizaron tres experimentos, en los que se evaluaron dosis y épocas de aplicación de GA3 (pre y posfloración), raleo manual de frutos del racimo y anillado de la rama con el fin de incrementar el tamaño de los racimos y las bayas. Se utilizó un diseño experimental de bloques completos al azar con cuatro repeticiones. Se evaluó el tamaño y peso del racimo y bayas, número de bayas por racimo y sólidos solubles totales. Los resultados muestran que la aplicación de GA3 en prefloración (10 ppm) incrementa el largo y diámetro polar de los racimos, mientras que el mayor diámetro ecuatorial, polar y el peso de las bayas se alcanzó con dos aplicaciones de GA3 en posfloración (40 + 20 ppm) o una aplicación de GA3 con 100 ppm. Estos resultados demuestran que la aplicación de GA3 es una tecnología que mejora la calidad física de las bayas y los racimos de uva.

Tree tomato (Solanum betaceum Cav.) is an Andean fruit crop that is grown in Ecuador. It is an exceptional source of minerals and vitamins, thus has nutraceutical properties. The objective of this research was to carry out a phytochemical characterization of a breeding population composed of 90 segregants. Pulp (including mesocarp, mucilage, seeds and placenta) was ground and sieved in order to obtain the liquid pulp to be lyophilized for the chemical analyzes. Antioxidants compounds were determined by spectrophotometry and vitamin C by reflectometry. Data were analyzed by principal components, grouping, and variance analyses; in addition, Z Score estimation was carried out to select elite individuals. There was a broad variability in the data obtained for the breeding population, polyphenol content varied from 5.11 to 16.59 mg GAE g−1, flavonoids from 1.24 to 6.70 mg cat g−1, carotenoids from 50.39 to 460.72 µg β-carotene g−1, anthocyanins from 1.06 to 240.49 mg cy-3-glu 100 g−1, antioxidant capacity from 49.51 to 312.30 µm Trolox g−1, and vitamin C from 78.29 to 420.16 mg 100 g−1. It can be concluded that tree tomato is a good source of beneficial biocompounds and has a high antioxidant capacity.

Tropical fruits are in high demand for their flavor and for their functional composition because these compounds are considered nutraceuticals. Passion fruit production is of economic importance to Ecuador; however, several Passiflora species are grown and each has to be analyzed to identify their phytochemical composition. In this study, the polyphenol, flavonoid, carotenoid, vitamin C, sugar and organic acid contents were determined. Six different Passiflora spp. germplasms were analyzed, coming from Passiflora edulis f. flavicarpa, Passiflora alata, Passiflora edulis f. edulis and unidentified Passiflora species (local germplasm). Measurement techniques included reflectometry for vitamin C, spectrophotometry for antioxidant compounds and HPLC for sugars and organic acids. Data were analyzed by principal component analysis, correlation and analysis of variance. Results showed that INIAP 2009 and P10 showed a high amount of polyphenols, antioxidant activity and citric content. Sweet passion fruit had the lowest vitamin C content while Gulupa showed the highest content. In terms of the local germplasm, POR1 showed the lowest content of flavonoids while PICH1 had high flavonoid and carotenoid content. Polyphenols were the main compounds that influenced antioxidant activity. This phytochemical information adds value to passion fruit as a nutraceutical source.

Tungurahua province has conditions suitable for growing deciduous fruit trees such as peach (Prunus persica L). This research aimed to identify the main factors influencing the production of this fruit crop and their effect on farmers income. Surveys were carried out directly to peach farmers in seven counties of Tungurahua such as Ambato, Cevallos, Mocha, Patate, Pelileo, Píllaro and Tisaleo. The results indicated that the most relevant factors were: farmer age, sown area, fruit selection, reason for fruit growing, type of production and production issues.

There is a high incidence of the nematode Meloidogyne incognita in several economically important species of Solanaceae. This nematode causes damage to the roots, leading even to the death of the plant, causing economic losses for the producer. This research was carried out in greenhouse to assess the response of five species of wild Solanaceae (Solanum auriculatum, S.hirtum, S.hispidum, S.arboreum and Nicotiana glauca) to the infestation of M. incognita was evaluated. A randomized block design with three replicates was used. The initial inoculum was obtained from infested roots of tree tomato (S. betaceum Cav.), which was propagated in kidney tomato plants (Lycopersicum esculentum Mill.) hibrid ‘Sheila’ which was used to inoculate the wild Solanaceae plus two susceptible controls (S. betaceum and S. quitoense) were inoculated with a dose of 2500 larvae. According to the reproduction factor of the nematode, S. arboreum, S. hirtum and N. glauca showed resistance because obtained values less than 1. In addition, S. hirtum (14.88) and N. glauca (22.67) showed the lowest number of root knots. In terms of foliage yield (dry weight), a response of tolerance was observed in all species except for the controls. It can be concluded that S. hirtum (compatible with S. quitoense - naranjilla) and N. glauca (compatible with S. betaceum - tree tomato) might be used as rootstocks of Solanaceae fruit crops of commercial importance in Ecuador, contributing to the integrated fruit production system.

Cherimoya (Annona cherimola Mill.) is native to the inter-Andean valleys of southern Ecuador and northern Peru. In Ecuador, the yield of this fruit crop is low, mainly due to agricultural management problems and poor fertilization. This research aims to assess the effect of native mycorrhizal fungi on seedling growth of cherimoya (cultivar 'Cangahua'). Sampling of soil and roots was carried out in 14 production sites of cherimoya. Soils that obtained the largest number of spores and greatest percentage of mycorrhizal colonization were those collected in Tumbabiro (plot 10), Gonzanamá, Paute and San Francisco de Atahualpa. These soils were used to propagate the inoculums in trap plants (Sorghum vulgare) and subsequently, they were used to inoculate the seeds and seedlings of cherimoya. There was no statistical difference to jointly analyze the results obtained in the inoculated seeds and seedlings. However, independently, the inoculum coming from the soil of Tumbabiro obtained the best results by doubling the content of total phosphorus and 47% increase in dry matter in cherimoya seedlings compared to control.

Tree tomato (Solanum betaceum Cav.) is an economically important fruit crop in Ecuador. The symptoms of higher virus-related incidence in plantations located in Pichincha and Tungurahua correspond to yellowing, mosaic, leaf deformation and blistering. This research carried out a diagnosis of the viruses present in these production areas using molecular techniques (RT-PCR) and electron microscopy. The identified viruses belonged to the genera Potyvirus (Potato virus Y; PVY), Polerovirus (Potato leaf roll virus; PLRV) and Tobamovirus (Tomato mosaic virus; ToMV), constituting a viral complex of at least two of the three viruses found. The symptomatology related to PVY was spots with tan or oily appearance and leaf deformation; in addition to these symptoms, yellowing and chlorosis were related to PLRV. Foliar blistering was related to the occurrence of the three viruses. The results indicated the presence of the three viruses in Tumbaco (Pichincha) and two (PLRV and PVY) in Pelileo (Tungurahua). PLRV was found in the 100% of the total samples, PVY in 50% of the Pelileo’s samples and ToMV only in Tumbaco. ToMV virus has been detected for the first time infecting tree tomato in Ecuador.

Cherimoya (Annona cherimola Mill.) is a commercially import fruit crop in several countries of Latin America (Ecuador, Peru and Chile) and Europe (Spain). The fruit is highly valued for its good organoleptic characteristics and nutritional value. Currently, there is a worldwide trend to implement high planting densities in several fruit crops. However, there is little information available on cherimoya to implement new commercial orchards. This research evaluated three planting densities (625, 1250 and 2500 plants/ha) to determine their effect on the cherimoya fruit quality of the variety 'Cumbe'. The two lowest densities evaluated doubled the yield compared to the highest density, and also obtained the highest percentages of fruit in the best size categories (super extra and extra), and harvesting fruit weights >400 g. Based on the results of this study, planting densities of 2500 plants/ha or higher are not recommended due to the affect on yield and quality of cherimoya fruit.

An application of a balanced nutrition will improve the soil as well as enhance the yield of naranjilla (Solanum quitoense Lam.) grown in the Ecuadorian Amazon. A field experiment was carried out in Palora, 16 de Agosto (Morona Santiago province) and Fátima (Pastaza province) to find which variables are related with the yield of the naranjilla crop and the yield response when the crop receives complete nutrition with N, P, K, Ca, Mg, and S plus lime and with the omission of each of these nutrients. A Random Complete Block Design with three replications was used in the three environments. The naranjilla crop had higher yields (18.14 Mg ha−1) in the complete treatments (N, P, K, Ca, Mg, and S) and without S and Mg, consequently, these two last nutrients did not limit the production. When N, P, K, and Ca were not applied, the yields fell to 14.62 Mg ha−1. The main environmental effect showed that Palora had the highest fruit yields (19.73 Mg ha−1), followed by 16 de Agosto (13.57 Mg ha−1) and finally Fátima with 11.04 (Mg ha−1). These preliminary results showed that with the treatments without S (18.55 Mg ha−1), without Mg (18.42 Mg ha−1) and complete (17.46 Mg ha−1) the highest yields were obtained, consequently, the production was not affected by the absence of these elements; the opposite happened when N, P, K, and Ca were not present.

Andean blackberries (Rubus glaucus Benth) are fruits rich in phytocomponents with high antioxidant activity. In this work, the changes in the total polyphenol content (TPC), the total flavonoid content (TFC), and the total anthocyanin content (TAC) of four blackberry varieties at three maturity stages (E1-25%, E2-50%, and E3-100%) were measured. The antioxidant activity (AA) was evaluated using the 2,2’azinobis-(3-ethylbenzthiazolin 6-sulphonic acid (ABTS) and ferric reducing antioxidant power (FRAP) methods. TPC and TFC content decreased with the increase in the maturity stage. The blackberry Brazos cultivar presented TPC values of 51.26, 38.16, and 31.59 mg of gallic acid equivalents (GAE)/g dry weight (DW) at E1, E2, and E3, respectively. The TAC and soluble solids increased with the increase in the maturity stage of the fruits. The Andimora variety at E3 presented a high TPC content, and the Colombiana variety presented a high TFC content. The blackberry Colombiana cultivar presented TAC values of 1.40, 2.95, and 12.26 mg cy-3-glu/100g DW at E1, E2, and E3, respectively. The blackberry Colombiana cultivar presented a high AA value at 1278.63 µmol TE/g DW according to the ABTS method and 1284.55 µmol TE/g DW according to the FRAP method. The TPC and TFC showed a high correlation with the AA according to the ABTS and the FRAP methods. The Pearson correlation between the TFC and AA/ABTS has a value of r = 0.92. The TFC and AA/FRAP present a value of r = 0.94.

La distancia de siembra junto a una adecuada fertilización nitrogenada influyen directamente en el rendimiento y calidad de fruta en la maracuyá cultivada en la Costa ecuatoriana, es por esto que tomar índices adecuados permitirá generar mayor ingreso a los productores.

La fruta de chirimoya es muy apetecida por su sabor y calidad nutritiva. Sin embargo, su producción es estacional y está controlada por diferentes procesos fenológicos y fisiológicos. Por esta razón, el uso de inductores para acelerar o retrasar la producción, permitirá obtener cosechas fuera de época.

La naranjilla es un frutal no tradicional de gran importancia económica en las estribaciones de la cordillera y la Amazonía ecuatoriana. Su fruta es muy apetecida debido a sus características físicas, químicas y organolépticas que le brindan calidad para su consumo; por tal motivo el fitomejoramiento de este frutal enfocado en la calidad de la fruta permite desarrollar nuevos materiales que posean las características deseadas por el mercado y la agroindustria.

En el cultivo de naranjilla y tomate de árbol, las arvenses presentes pueden ser hospederas de insectos parasitoides que permiten un control biológico natural de plagas. En este estudio se muestreó especies arvenses en las localidades de El Chaco (Napo) y Río Negro (Tungurahua) donde las familias encontradas mayoritariamente fueron Asteraceae, Poaceae y Cyperaceae.

Neoleucinodes elegantalis (Guenée) is an oligophagous species of plants in the Solanaceae family that has a broad geographical distribution in the tropical zones of South America. It is the most important insect pest of naranjilla (Solanum quitoense Lamarck), a crop grown in threatened areas of the tropical old-growth forest in Ecuador. In this study, two host-specific populations of N. elegantalis were collected from infested fruit of naranjilla and tree tomato (Solanum betaceum Cavanilles) in different locations. Sexually virgin adult insects (93 females and 103 males) were dissected to extract their genitalia to measure 12 morphological variables in females and six in males, resulting in six and four informative variables respectively. Using univariate and multivariate analysis of variance, it was found that the Solanaceous host was the main factor differentiating the area measurements of the seventh abdominal segment and ostium bursae in female genitalia, and cornuti length in male genitalia. Principal components generated with these measurements were employed in a logistic regression model for the classification of the Solanaceous host. Female genitalia of individuals from S. betaceum showed significantly larger ostium bursae relative to female genitalia from S. quitoense. For males, individuals collected from S. betaceum showed longer cornuti length than samples collected from S. quitoense. The results suggest genotypic differentiation according to the Solanaceous host or phenotypic plasticity in N. elegantalis. Further molecular and bio-geographical studies are needed to properly differentiate N. elegantalis populations that would help in the control of this pest.