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1.
J Sci Food Agric ; 100(4): 1827-1831, 2020 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-31875429

RESUMEN

BACKGROUND: Agriculture is the main means of subsistence for most of the population in developing countries. Crops that can increase their value with in situ processing have a big impact on the small landholder's economics. Moreover, crops such as coffee and cocoa beans have been very important for Ecuadorian farmers. In this study, we wanted to analyze if the climatic conditions exist for growing high-quality tea in Ecuador and determine the areas that will be less affected by global climate change in the future. RESULTS: We used a GIS (geographic information systems) based analysis, together with ecological niche modeling to determine areas in Ecuador where Ceylon and Nilgiris tea varieties could be grown, which will maintain similar ecological conditions in the future, and have a high agricultural aptitude. In total, there are more than 150 000 ha in Ecuador that could be converted to high-quality tea plantations, most of them in the coastal provinces, with some specific areas in the Andean foothills. CONCLUSION: Ecuador has a significant amount of land with the potential to grow high-quality tea, with no significant ecological niche modifications due to climate change in the long-term future. Tea is a viable and potentially highly profitable crop for small landholders and should be considered by local stakeholders. © 2019 Society of Chemical Industry.


Asunto(s)
Agricultura/economía , Camellia sinensis/crecimiento & desarrollo , Cambio Climático , Productos Agrícolas/economía , Productos Agrícolas/crecimiento & desarrollo , Ecosistema , Ecuador
2.
Evolution ; 72(1): 95-112, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29094340

RESUMEN

Parasite diversity accounts for most of the biodiversity on earth, and is shaped by many processes (e.g., cospeciation, host switching). To identify the effects of the processes that shape parasite diversity, it is ideal to incorporate both deep (phylogenetic) and shallow (population) perspectives. To this end, we developed a novel workflow to obtain phylogenetic and population genetic data from whole genome sequences of body lice parasitizing New World ground-doves. Phylogenies from these data showed consistent, highly resolved species-level relationships for the lice. By comparing the louse and ground-dove phylogenies, we found that over long-term evolutionary scales their phylogenies were largely congruent. Many louse lineages (both species and populations) also demonstrated high host-specificity, suggesting ground-dove divergence is a primary driver of their parasites' diversity. However, the few louse taxa that are generalists are structured according to biogeography at the population level. This suggests dispersal among sympatric hosts has some effect on body louse diversity, but over deeper time scales the parasites eventually sort according to host species. Overall, our results demonstrate that multiple factors explain the patterns of diversity in this group of parasites, and that the effects of these factors can vary over different evolutionary scales. The integrative approach we employed was crucial for uncovering these patterns, and should be broadly applicable to other studies.


Asunto(s)
Enfermedades de las Aves/parasitología , Columbidae , Infestaciones Ectoparasitarias/veterinaria , Neoptera/clasificación , Neoptera/genética , Américas , Animales , Interacciones Huésped-Parásitos , Neoptera/fisiología , Filogeografía
3.
Ecol Evol ; 7(11): 3724-3731, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28616169

RESUMEN

Parasite lineages commonly diverge when host lineages diverge. However, when large clades of hosts and parasites are analyzed, some cases suggest host switching as another major diversification mechanism. The first step in host switching is the appearance of a parasite on an atypical host, or "straggling." We analyze the conditions associated with straggling events. We use five species of colonially nesting seabirds from the Galapagos Archipelago and two genera of highly specific ectoparasitic lice to examine host switching. We use both genetic and morphological identification of lice, together with measurements of spatial distribution of hosts in mixed breeding colonies, to test: (1) effects of local host community composition on straggling parasite identity; (2) effects of relative host density within a mixed colony on straggling frequency and parasite species identity; and (3) how straggling rates are influenced by the specifics of louse attachment. Finally, we determine whether there is evidence of breeding in cases where straggling adult lice were found, which may indicate a shift from straggling to the initial stages of host switching. We analyzed more than 5,000 parasite individuals and found that only ~1% of lice could be considered stragglers, with ~5% of 436 host individuals having straggling parasites. We found that the presence of the typical host and recipient host in the same locality influenced straggling. Additionally, parasites most likely to be found on alternate hosts are those that are smaller than the typical parasite of that host, implying that the ability of lice to attach to the host might limit host switching. Given that lice generally follow Harrison's rule, with larger parasites on larger hosts, parasites infecting the larger host species are less likely to successfully colonize smaller host species. Moreover, our study supports the general perception that successful colonization of a novel host is extremely rare, as we found only one nymph of a straggling species, which may indicate successful reproduction.

4.
Ecol Evol ; 5(16): 3264-71, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26380662

RESUMEN

Parasites comprise a significant percentage of the biodiversity of the planet and are useful systems to test evolutionary and ecological hypotheses. In this study, we analyze the effect of host species identity and the immediate local species assemblage within mixed species colonies of nesting seabirds on patterns of genetic clustering within two species of multihost ectoparasitic lice. We use three genetic markers (one mitochondrial, COI, and two nuclear, EF1-α and wingless) and maximum likelihood phylogenetic trees to test whether (1) parasites show lineage sorting based on their host species; and (2) switching of lineages to the alternate host species depends on the immediate local species assemblage of individual hosts within a colony. Specifically, we examine the genetic structure of two louse species: Eidmanniella albescens, infecting both Nazca (Sula granti) and blue-footed boobies (Sula nebouxii), and Fregatiella aurifasciata, infecting both great (Fregata minor) and magnificent frigatebirds (Fregata magnificens). We found that host species identity was the only factor explaining the patterns of genetic structure in both parasites. In both cases, there is evident genetic differentiation depending on the host species. Thus, a revision of the taxonomy of these louse species is needed. One possible explanation of this pattern is extremely low louse migration rates between host species, perhaps influenced by fine-scale spatial separation of host species within mixed colonies, and low parasite infrapopulation numbers.

5.
J Parasitol ; 100(5): 569-77, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24911632

RESUMEN

In this paper we describe the ectoparasitic lice (Insecta: Phthiraptera) found on 5 species of seabirds (magnificent frigatebird Fregata magnificens; great frigatebird Fregata minor ; Nazca booby Sula granti ; blue-footed booby Sula nebouxii ; and red-footed booby Sula sula ) on the Galapagos Archipelago. We found 9 species of ectoparasitic lice: 5 species of Pectinopygus ischnocerans, 1 infesting each host; 2 species of Colpocephalum amblyceran lice, 1 on each frigatebird species; and 2 shared amblycerans, Eidmanniella albescens (Piaget, 1880) found on Nazca and blue-footed boobies and Fregatiella aurifasciata (Kellogg, 1899) found on the 2 frigatebirds. We tested the relative importance and interactions of host sex, body size, host, island, host family, and breeding status and found that inter-island differences were the main predictors of prevalence and infestation intensity. These differences could be related to host density or weather, but further evidence is needed.


Asunto(s)
Amblycera/crecimiento & desarrollo , Enfermedades de las Aves/parasitología , Ischnocera/crecimiento & desarrollo , Infestaciones por Piojos/veterinaria , Amblycera/clasificación , Amblycera/genética , Animales , Enfermedades de las Aves/epidemiología , Aves , ADN/química , ADN/aislamiento & purificación , Código de Barras del ADN Taxonómico , Ecuador/epidemiología , Femenino , Interacciones Huésped-Parásitos , Ischnocera/clasificación , Ischnocera/genética , Infestaciones por Piojos/epidemiología , Infestaciones por Piojos/parasitología , Masculino , Ninfa , Prevalencia , Factores Sexuales , Razón de Masculinidad , Especificidad de la Especie
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