Search

The cultivation of naranjilla represents one of the significant economic sectors at the level of the eastern communities of Ecuador, being a crop widely accepted both in the national and foreign markets. Among the main limitations that affect production and make it unprofitable are pests and diseases that limit its performance, using excessive use of pesticides to counteract the problems presented in situ. Taking into account the incidence of pests, these can be the main spreaders of more complex diseases such as viruses. In several locations in the Limón-Indanza canton, the incidence of possible symptoms related to viruses has been witnessed, such as: chlorosis, wrinkling of leaves, internerval mosaics, underdevelopment in plants, fruit abortion, highlighting the presence of possible viruses among different locations. The objective of this study was to characterize the viral isolates from 4 naranjilla producing localities in two species of the Lasiocarpa group, (S. quitoense and S. lasiocarpum), mechanical inoculations were carried out in the two species, evaluating the incidence and severity of the symptoms. Observed in the experimental units, a completely randomized design was carried out, for the severity variable it was measured at 15, 35 and 56 dai (days after inoculation), there were differences between the control and the viral isolates for each of the species. It was also identified that S. quitoense was more susceptible to damage than S. lasiocarpum. In the molecular part, no amplifications were observed with the primers used for PCR. In addition, the symptoms observed for each viral isolate were characterized, this work being a contribution of continuity and information for the southern region of the country.

The cultivation of naranjilla (Solanum quitoense Lam.) represents one of the most important economic activities for a large number of communities in Ecuador. This crop is limited mainly by the affection of certain pathogens such as the nematodes Meloidogyne incognita together with the fungus Fusarium oxysporum, which are responsible for the deterioration in the development of the plants already established in the field. For this reason, the following study aims to evaluate a population of segregants of the cross between S. quitoense and the wild species S. lasiocarpum reported as resistant to the interaction between M. incognita and F. oxysporum, to determine the level of damage and to evaluate microsatellite molecular markers and RGAs. This research was carried out in two stages: a greenhouse stage in which the segregants infected with pathogens were evaluated after 90 days, where damage was analyzed at the morphological level; and a stage in the Biotechnology laboratory of the Faculty of Agricultural Sciences, in which different combinations of primers associated with resistance in other solanaceae were tested. The first phase involved inoculations in 12 populations (10 segregants, S. quitoense and S. lasiocarpum). A completely randomized design (CRD) was used in a 4x12 factorial arrangement, with four replications. The second phase was carried out in the laboratory where SSR and RGA molecular markers associated with resistance were analyzed for both the parents and the 10 segregating populations resulting from the cross between S. quitoense and S. lasiocarpum. According to the results obtained, it was observed that certain segregants and the parental S. lasiocarpum obtained the best results, since they showed significant differences compared to S. quitoense, the latter being susceptible compared to the other populations. As for molecular analysis, no amplifications were observed with the primers used for PCR

Anthracnose known as "chicken eye", caused by the phytopathogenic fungus Colletotrichum sp, which is widely distributed in production areas, is the most important disease, since the pathogen not only attacks the fruit at any phenological stage but also the leaves, branches and inflorescences, thus reducing the productive life of the tree by up to 50%. The aim of the present investigation was to evaluate, under in vitro conditions, biofungicides and salicylic acid against chemical products for the control of anthracnose in tree tomato. Samples were taken from 12 farms distributed in the provinces of Azuay, Loja and Cañar. For the collection, the fruits presented the characteristics of the disease as black lesions, accompanied by masses of pink conidia. These samples were subjected to isolation and purification for inhibition tests. The treatments evaluated were salicylic acid 0.4mM, Bacillus subtilis 5ml/L, Bacillus pumilus 5ml/L, pyraclostrobin 13.3% + epoxiconazole 5% 1ml/L, captan 1g/L, difenoconazole 0.75ml/L, and iprodione 1ml/L plus a control treatment. At the in vitro level, salicylic acid inhibited mycelial growth of Colletotrichum sp. from samples collected in the provinces of Azuay, Loja and Cañar, while the T5 treatment (captan) inhibited mycelial growth in samples from Azuay and Loja in the localities of Don Julo, Urdaneta and Saraguro.

Root knot nematode M. incognita is one of the most dangerous and common species affecting Solanaceae family, including the naranjilla crop (S. quitoense). The objective of this work was to evaluate three species of Solanaceas as hosts (S. sessiliflorum, S. hirtum and S. quitoense) for an isolated of M. incognita in greenhouse. Plants of three species were planted in pots and each plant was inoculated with 2500 eggs and second stage juveniles (J2). Host suitability was assessed 80 days after inoculation. Initial inoculum was obtained from infested roots of S. quitoense plants collected in commercial naranjilla orchards. A completely randomized experimental design was used. The variables evaluated at 80 days after inoculation were: gall index (GI), nematode reproduction factor (RF), dry weight of the foliar area, plant height and stem diameter. All species were galled, but S. sessiliflorum and S. hirtum showed the least number of root knots with values of 33.73 and 34.73. Both were classified as resistant / hypersensitive with reproduction factors of 0.94 and 0.85 (RF> 1) respectively, while S. quitoense was susceptible with a value of 1.56. In terms of foliage yield (dry weight), plant height and stem diameter, S. sessiliflorum and S. hirtum showed a tolerance response in relation to S. quitoense.

In this work, the morphological characterization and the resistance to powdery mildew of eight kidney tomato cultivars (New Yorken, Rodade, Rosa de Berna, Lignon, Caraibo, LA1033, LA3863, Sheila), improved by INRA (National Institute of Agricultural Research) were evaluated. of France), for this it was carried out in the canton of Cuenca, province of Azuay, implanting the cultivation under plastic cover with a completely random design (DCA). The parameters measured in the trial were: emergence percentage, setting percentage, plant height, number of leaves, stem diameter, days to flowering, number of flowers per cluster, number of fruits per cluster, fruit weight, incidence and severity of powdery mildew. The LA1033 and LA3863 cultivars obtained 100% germination, while the yield for the Caraibo cultivar was the lowest with 78%, a lower value than the other varieties whose values were 100%, the LA 1033 cultivar presented higher foliage with an average of 14.44 leaves eighty days after transplanting. The LA3863 cultivar was the earliest for days to flowering with an average of 53.56 days. With regard to powdery mildew, infection occurred only in the Lignon and Rodade cultivars with a severity value of 1.98% for Lignon and 4.8% for Rodade, characterizing them as tolerant, however, the rest of the cultivars have immunity characteristics. in which they were not infected with powdery mildew, in addition, no fruiting was obtained for cultivars LA1033 and LA3863, so their use is not recommended for local conditions.

In the cantons Guachapala and Paute, Solanum betaceum (tomate de árbol), is a fruit tree highly cultivated, and base of local economy. Just like another crops, the performance of this crop has been affected by different pathogens, such as: bacteria, fungus, etc. In addition to this problems, viral diseases symptoms has been observed, nevertheless, there are not studies that afford to know the etiological origin of theses. This research diagnosed by the molecular and the symptomatic way the phytopatogens viruses in tomato tree in the cantons Guachapala and Paute. Firstly, leaves with the most common symptoms of virosis were collected (chlorosis, mosaics, leaf deformation, blistering and mottling). Then of each tomato producer locality, a viral isolated were obtained and, it was inoculated in healthy seedling plants. The symptoms were development for eight weeks and after that, the morphological and molecular analysis was carried out. Morphological, the incidence and severity of each symptom was analyzed, where the leaf deformation was the symptom with the higher incidence 69,52% follow by blistering 54,35%. In the case of mosaics, chlorosis and mottles, the higher incidence observed was: 49,92%, 50% and 51,36%, respectively. According to the literature, the inducted symptoms by the different viral isolates belongs to viral diseases being the PLRV and PVY the main causals agents of all the analyzed symptoms. With the exception of leaf deformation, the AMV has been related with the others symptoms analyzed, and it is possible that the blistering is the product of the interaction between three causal agents: PLRV, PVY and ToMV. In this study, no one amplification was observed with the primers used.

In Ecuador, one of the factors that limit wheat production are diseases, one of the most important being the disease called “fusariosis” of the ear of wheat. This disease is caused by various species of the fungus Fusarium spp. This disease is of great economic importance because it can reduce production by more than 50%. The present research work was carried out in a greenhouse, in order to evaluate the resistance of six wheat varieties previously described as resistant to infection by three strains of Fusarium spp. The morphological characterization of the strains was carried out based on taxonomic keys and for molecular identification, PCR was used through the use of specific primers for Fusarium graminearum, defined in the galacto oxidase gene (gaoA). Punctual inoculation of three strains of Fusarium spp., was carried out in wheat ears at the anthesis stage. All the wheat varieties evaluated presented a reaction of resistance to Fusarium, also the three strains of Fusarium spp. were able to infect all wheat cultivars and induced the characteristic symptoms of Fusarium head blight (TEF). There were highly significant differences between the strains regarding the measurement of the incidence and severity variables. According to the cultural and morphological characteristics observed in carnation leaf agar medium (CLA), the three strains were identified within the genus Fusarium, but it was not possible to confirm to which species they belonged. There was no PCR amplification with the specific primers designed for F. graminearum.

Anthracnose is a fungal disease that causes serious losses in the cherimoya crop in Ecuador. The disease causes serious damage to the fruit and its control is mainly based on the use of chemical products. According to studies, Colletotrichum spp. has been reported as the causal agent of anthracnose in cherimoya, but the species has not been defined. In the present study, the morphological characterization and molecular identification of 10 strains of Colletotrichum spp. of cherimoya was carried out in different localities of the province of Azuay. For morphological characterization, the variables evaluated were: colony growth, colony coloration, colony type and conidial shape. For molecular identification, PCR analysis was performed with specific primers reported for C. gloeosporioides and C. acutatum, designed in the internal transcribed spacer (ITS). Based on the morphological characteristics and PCR analysis, it was determined that in Guachapala canton the pathogen responsible for anthracnose corresponds to a complex of C. gloeosporioides and C. acutatum, while in Gualaceo the species causing the disease is C. acutatum.

Naranjilla or lulo (Solanum quitoense) is an important native fruit crop to northwestern South America. It is planted mainly in Colombia and Ecuador and is increasingly in demand worldwide. However, it is very susceptible to attack by pests and diseases. In Ecuador, the main pathogens that attack naranjilla are Fusarium oxysporum and Meloidogyne incognita. In addition, a virus of the Tymoviridae family has been detected, which was called Naranjilla chlorotic mosaic virus (NarCMV) and a viru that causes mosaic that has been called Naranjilla mild mosaic virus (NarMMV). Presence of these pathogens has been detected in using different molecular techniques. This report presents the current status in the use of molecular markers, both in diagnosis of diseases and in detection of information related to resistance in naranjilla crop.

The naranjilla is an important item for the southern Amazon of Ecuador because it is one of the main sources of income for local families. However, it has great limitations caused by pests and diseases. The lack of information on viral infections in the Amazon south of the Equator, encouraged the realization of this study, whose objective was to determine the molecular identity and characterize the symptoms of asylees viral naranjilla of 4 commercial lots of the canton Palanda in 3 species of the section lasiocarpa (S. quitoense, S. hirtum and S. sessiflorum). Mechanical inoculations of viral isolates were performed in the 3 species and the incidence and severity of symptoms were evaluated. A completely random design was applied and the variables were measured at 20, 25 and 30 dpi. There was a statistically significant difference in the severity variable (Tukey p < 0.05) between the control and the 4 viral isolates in each species. In addition, a higher level of damage caused by isolates was determined in S. quitoense than in S. sessiflorum and S. hirtum. To determine the molecular identity, 16 solanaceaes virus primers were evaluated using the RT-PCR technique. The presence of a viral complex between CMV and PYVV was identified. In addition, the symptomatology of this viral complex was characterized, consisting of intervenal chlorosis, leaf wrinkles, necrosis, mosaics, chlorotic rings, leathery leaves, among others. It is the first report of mixed infection of viruses that infect the naranjilla in Ecuador and is of great value given the obvious deficiencies of information currently available on the causative agents of virosis in this crop.

In Ecuador, cultivation of naranjilla crop (Solanum quitoense Lam.) is mainly limited by the nematode Meloidogyne incognita and the fungus Fusarium oxysporum. Interaction between these two pathogens causes low production and in some cases total loss of the crop. This research was carried out with the objective of evaluating the resistance to interaction between M. incognita and F. oxysporum in two species of the Lasiocarpa section: Solanum hirtum and Solanum sp. The study consisted of two phases: first, inoculation of M. incognita and F. oxysporum for three species on greenhouse; and, second, search for molecular markers associated with resistance. For the first phase, seedlings of approximately two months old of S. hirtum, Solanum sp. and S. quitoense (sensitive control) were inoculated with M. incognita and F. oxysporum. A randomized complete block design (DBCA) in a 3x3 factorial arrangement with five repetitions was used. For the second phase, molecular markers SSR and RGAs associated with resistance were analyzed in the Molecular Biology Laboratory of the University of Cuenca for parents and a segregating population of S. hirtum x S. quitoense cross. The results showed indicate that S. hirtum and Solanum sp. obtained the best performances in terms of the variables accumulated biomass, height, stem diameter, degree of discoloration and degree of severity of wilting, since they presented significant differences compared to the sensitive control S. quitoense. Two SSR markers and four RGAs markers based on resistance genes showed polymorphism. They amplified only in S. hirtum, and presented polymorphism in the segregating population of the S. hirtum x S. quitoense cross.

Tree tomato is a crop of Andean origin. This is cultivated mainly in South America and it is increasingly in demand worldwide. However, it is a crop very susceptible to pests and diseases. There are currently improvement programs to obtain resistant cultivars that include wild species for introgression of features of interest such as disease resistance and improvement of fruit quality in commercial plantations. However, although some segregators of the crosses made have shown resistance in field conditions, the information available regarding molecular markers useful in the interactions of this crop with its main pathogens is scarce. In Ecuador, the main pathogens that attack tree tomatoes are Colletotrichum sp., Meloidogyne sp. and virus species classified in six genera: Potyvirus, Cucumovirus, Tospovirus, Tobamovirus, Potexvirus and Polerovirus. The presence of these pathogens has been detected with the use of different molecular techniques. This report presents the current status in the use of molecule markers, both in the diagnosis of diseases, and in the detection of resistance-related information.

The naranjilla crop has a great potential in Ecuador, due to its excellent organoleptic characteristics. Nevertheless, the crop has a high susceptibility to attack of nematode Meloydogyne incognita, sometimes occasioning the total loss of crop. This research was carried out under greenhouse and the objectives were: determine the resistance to Meloidogyne incognita, in three species of the Lasiocarpa section: S. quitoense, S. hirtum and Solanum sp; and, find RGAs and SSR molecular markers associated with resistance. For phenotypic analysis, a completely randomized design with five repetitions was used, and for molecular analysis the polymorphism based on absence or presence of amplification products was considered. Nematode inoculum was extracted from roots infected with naranjilla. For molecular analyzes, we used RGAs and SSR primers defined on homology regions for crop resistance genes previously identified. We found that for variables: accumulated biomass, population increase, incidence, index of knotty and severity, results showed highly significant differences between S. hirtum and Solanum sp. with respect to susceptible specie (S. quitoense) at 80 days of evaluation. Regarding the molecular markers, we found two pairs of primers that amplified in S. hirtum and S. quitoense: an RGA defined on an LRR domain and an SSR defined in pepper. No amplifications were obtained in Solanum sp. Furthermore, these primers were found to be polymorphic in the segregating population between S. quitoense and S. hirtum.

Anthracnose is a fungal disease that causes serious losses in tree tomatoes in Ecuador. This disease causes serious damage to fruits and its control is based mainly on use of chemical products. In Ecuador, the genera Colletotrichum acutatum and Colletotrichum gloeosporioides have been reported to be the causal agent of anthracnose, based on morphological characteristics. In this study, the morphological and molecular characterization of 16 isolates of Colletotrichum spp. of tree tomato, in six different localities in the provinces of Azuay and Loja. Morphological characterization was carried out for variables such as colony color and conidium shape, while molecular characterization was performed by polymerase chain reaction (PCR). PCR experiments was carried out with specific primers reported for C. acutatum and C. gloeosporioides, designed in the internal transcription spacer (ITS). Based on morphological and molecular characterization, it was determined that the causative agent of anthracnose for the provinces of Azuay and Loja is the C. acutatum complex, represented by C. tamarilloi. Isolates presented characteristics of this species and molecular analysis allowed to confirm this result, generating amplifications of molecular weights of approximately 500 bp, while with the specific primers of C. gloeosporioides no amplification was obtained. This molecular characterization confirms results that place the C. acutatum complex as the causative agent of anthracnose in the Southern region of Ecuador.

Spodoptera frugiperda is an insect pest of corn. This polyphagous species is included within the group of the armyworms, considered pests of economic importance in several countries of America. In corn, these larvae cause damage from the seedling to pre-ripeness stages. Identification of Lepidoptera is usually based on the morphology of adults, meaning that larvae must reach adulthood for their identification. Nevertheless, the larval period is the stage that causes mayor damage in corn. Currently, the use of molecular tools such as PCR, based on mitochondrial or nuclear DNA sequences, has been used for unambiguous identification of pests or biotypes from larvae. The objective of this study was to identify the presence of S. frugiperda species in white corn crops in the South of Ecuador at molecular level. For this, we used a PCR analysis with specific primers for S. frugiperda at the level of the mitochondrial gene of subunit 1 cytochrome oxidase (COI) I. A total of 360 larvae were collected in 36 sites distributed in three provinces: 18 in Azuay, 12 in Cañar and 6 in Loja, between January and March 2015. As a result, amplifications of molecular weights of approximately 500 pb corresponding to S. frugiperda were generated. This molecular characterization is, to our knowledge, the first one performed for the Austro of Ecuador.

In the Andean mountains of southern Ecuador there are areas occupied by high Andean secondary forests as a consequence of anthropic activities. Here we identify different secondary forest communities located over 2900 m a.s.l, based on its floristic similarity. In each community, floristic composition was described by the total exclusive and shared species. Estimation curves were used to provide richness and diversity metrics. The structure was analyzed according to abundance and basal area. In addition, we evaluated the role of environmental variables in floristic conformation and structure through principal components and the redundancy analysis. Three forest communities were identified. Community, located at high altitude and low temperature, had the highest value of diversity and basal area. Variation in species composition was explained by climatic and geographic variables, density by soil and climatic variables, and basal area by topographic variables. Species richness and basal area did not present an altitudinal distribution pattern similar to those from other Andean tropical forests. Therefore, the floristic variation, species richness and basal area seem to be explained by the chronological age of secondary succession, as evidenced by the indicator species belonging to different ecological groups. We concluded that the floristic composition, richness and structure of vegetation in forest communities of high Andean secondary forests are influenced by climatic, topographic, physiographic and geographic variables related to the age of succession.

Semi-deciduous forest has provided historically non-timber forest products (NTFP) to neighbor populations. However, information about use of their floristic resources is scarce. In this research, we evaluated the state of knowledge of NTFPs for two floristic floors in semi-deciduous forest: Montane and Montane low. We applied semi-structured surveys to investigate the plant uses that provide NTFPs to three age groups. Plant uses were differentiated into nine categories of use. We collected NTFPs at each sampling site where they grow naturally or in home gardens, and then identified taxonomically. We determined the Use Value by use category; the Total Use Value by species, and by species disaggregated by sex and age group. For floristic levels, the food and bev-erage category presented the highest use value. Within the age group of young people in floristic levels, the species belonging to the medicinal category were the most important with similar val-ues for men and women. In adults, in the piedmont level, forage species were the most important, with similar values for men and women. For the elderly, in the two plant formations several species stand out belonging to different categories of uses with similar values. We concluded that knowl-edge about the use is still valid in the three age groups according to the trend of knowledge levels. In the elderly, this knowledge is pragmatic and real, which is transmitted to adults and young peo-ple. In the group of young people, its application is uncertain.