Publicaciones

@article{nokey,

title = {Anthropogenic dispersion of selected germplasm creates a geographic mosaic of contrasting maternal lineages in Crescentia cujete from Mesoamerica},

author = {Xitlali Aguirre-Dugua and Jesús Llanderal-Mendoza and Antonio González-Rodríguez and Luis E. Eguiarte and Alejandro Casas},

doi = {10.1007/s11295-018-1230-8},

issn = {16142950},

year  = {2018},

date = {2018-01-01},

journal = {Tree Genetics and Genomes},

volume = {14},

issue = {2},

publisher = {Springer Verlag},

abstract = {The modification of the genetic/phenotypic composition of plant populations through artificial selection occurs both through time and space. We analyzed the role of human dispersal on the geographic distribution of maternal lineages of Crescentia cujete in Mesoamerica. We sampled 28 homegarden (224 individuals) and 12 wild populations (159 individuals). Semi-structured interviews provided information on the origin of cultivated trees. Six chloroplast microsatellites allowed for the identification of 21 haplotypes, four of them exclusively in 83% of homegarden trees. Wild haplotypes from local C. cujete and Crescentia alata were found at low frequencies (17%) under cultivation. Cultivated and wild haplotypes constituted two different haplogroups. Accordingly, barriers to seed dispersal were detected among neighboring cultivated and wild populations. Recorded events of human dispersal of cuttings and seeds attaining up to > 200 km agreed with homegardens’ lower diversity (Nei’s h = 0.55, dropping to 0.32 when excluding wild haplotypes). Wild populations displayed high diversity (h = 0.71) and isolation by distance, in agreement with physiographic provinces. Our results support the native status of wild C. cujete and a Pre-Columbian introduction of cultivated lineages that generated a novel genetic mosaic superimposed on native maternal lineages. The results reveal the active role of farmers in maintaining the identity of cultivated lineages through time, while chloroplast capture from local congeners has increased the diversity of maternal lineages under cultivation. Additional data are needed on the origins of cultivated lineages, but our results contribute new insights into tree domestication in this center of crop diversity.},

keywords = {Bignoniaceae, Crescentia cujete, Homegarden, Mesoamerica, Perennial, Tree domestication},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Round and large: Morphological and genetic consequences of artificial selection on the gourd tree Crescentia cujete by the Maya of the Yucatan Peninsula, Mexico},

author = {Xitlali Aguirre-Dugua and Luis E. Eguiarte and Antonio González-Rodrgíuez and Alejandro Casas},

doi = {10.1093/aob/mcs068},

issn = {03057364},

year  = {2012},

date = {2012-01-01},

journal = {Annals of Botany},

volume = {109},

issue = {7},

pages = {1297-1306},

abstract = {Background and AimsArtificial selection, the main driving force of domestication, depends on human perception of intraspecific variation and operates through management practices that drive morphological and genetic divergences with respect to wild populations. This study analysed the recognition of varieties of Crescentia cujete by Maya people in relation to preferred plant characters and documents ongoing processes of artificial selection influencing differential chloroplast DNA haplotype distribution in sympatric wild and home-garden populations. MethodsFifty-three home gardens in seven villages (93 trees) and two putative wild populations (43 trees) were sampled. Through semi-structured interviews we documented the nomenclature of varieties, their distinctive characters, provenance, frequency and management. Phenotypic divergence of fruits was assessed with morphometric analyses. Genetic analyses were performed through five cpDNA microsatellites. Key ResultsThe Maya recognize two generic (wild/domesticated) and two specific domesticated (white/green) varieties of Crescentia cujete. In home gardens, most trees (68%) were from domesticated varieties while some wild individuals (32%) were tolerated. Cultivation involves mainly vegetative propagation (76%). Domesticated fruits were significantly rounder, larger and with thicker pericarp than wild fruits. Haplotype A was dominant in home gardens (76%) but absent in wild populations. Haplotypes B-F were found common in the wild but at low frequency (24%) in home gardens. ConclusionsThe gourd tree is managed through clonal and sexual propagules, fruit form and size being the main targets of artificial selection. Domesticated varieties belong to a lineage preserved by vegetative propagation but propagation by seeds and tolerance of spontaneous trees favour gene flow from wild populations. Five mutational steps between haplotypes A and D suggest that domesticated germplasm has been introduced to the region. The close relationship between Maya nomenclature and artificial selection has maintained the morphological and haplotypic identity (probably for centuries) of domesticated Crescentia despite gene flow from wild populations. © The Author 2012. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved.},

keywords = {Artificial selection, Bignoniaceae, Crescentia cujete, domestication, Maya, Mesoamerica, Microsatellites, traditional plant management},

pubstate = {published},

tppubtype = {article}

}