Earth Ovens (<Emphasis Type="Italic">Píib</Emphasis>) in the Maya Lowlands: Ethnobotanical Data Supporting Early Use

Earth Ovens ( Píib ) in the Maya Lowlands: Ethnobotanical Data Supporting Early Use. Earth oven cooking is very important among the Yucatec Maya. It is used for daily, festive, and ceremonial occasions, contrasting with other Mesoamerican cultures that use this technique sporadically. In this paper we present an ethnobotanical analysis of the use of earth ovens in a Maya community in Yucatan, Mexico, and discuss its possible antiquity, probable reasons for its continuity, and its current and past importance. We found four oven types in daily use as well as in ritual and celebratory contexts. These involve both men and women in a way that favors transmission of traditional knowledge to the next generation and promotes social bonding and ethnic identity. Of the 46 plant species used in their construction or for the dishes cooked in them, 82% are native and produced in traditional agricultural systems: milpa (kool in Maya) maize-bean-squash association and conuco (pach pakal in Maya) based on tubers such as manioc (Manihot esculenta Crantz). Research suggests that this food preparation technology has the same antiquity as its associated agricultural systems (approximately 3400 to 3000 B.C.E.). Earth ovens were probably used to cook roots and meat in the Archaic and then to cook tamales (vegetal-wrapped maize dough) beginning in the Preclassic. Continuity of traditional agricultural and cultural practices has favored preservation of earth ovens.     

Genetic diversity and structure of a worldwide collection of Phaseolus coccineus L

Phaseolus coccineus L. is closely related to P. vulgaris and is the third most important cultivated Phaseolus species. Little is known about the patterns of its diversity. In this work, a representative collection of its worldwide diversity was initially developed. The collection includes 28 wild forms (WFs) and 52 landraces (LRs) from Mesoamerica (the crop domestication area), and 148 LRs from Europe (where the crop was introduced in the sixteenth century). The collection was studied by using 12 SSR molecular markers that were developed for the P. vulgaris genome. They were proved to be effective and reliable in P. coccineus in this work. Fourteen LRs of P. dumosus (previously identified as a subspecies of P. coccineus) were also studied. The genetic diversity, population structure and phylogenetic relationships were investigated. The results indicate that: (a) the European and Mesoamerican gene pools are clearly differentiated, (b) a certain reduction of diversity occurred with introduction into Europe, and (c) the Mesoamerican LRs (P. dumosus included) and WFs are closely related and are connected by a high gene flow. Inferences on the domestication process of P. coccineus are also presented. This study provides a picture of the genetic diversity distribution and outcomes with introduction into the Old World, which was not available before. It also underlines that the genetic diversity of both WFs and LRs is an important source for Phaseolus spp. breeding programs and deserves to be preserved in situ and ex situ.     

Microsatellite diversity and genetic structure among common bean (Phaseolus vulgaris L.) landraces in Brazil, a secondary center of diversity

Brazil is the largest producer and consumer of common bean (Phaseolus vulgaris L.), which is the most important source of human dietary protein in that country. This study assessed the genetic diversity and the structure of a sample of 279 geo-referenced common bean landraces from Brazil, using molecular markers. Sixty-seven microsatellite markers spread over the 11 linkage groups of the common bean genome, as well as Phaseolin, PvTFL1y, APA and four SCAR markers were used. As expected, the sample showed lower genetic diversity compared to the diversity in the primary center of diversification. Andean and Mesoamerican gene pools were both present but the latter gene pool was four times more frequent than the former. The two gene pools could be clearly distinguished; limited admixture was observed between these groups. The Mesoamerican group consisted of two sub-populations, with a high level of admixture between them leading to a large proportion of stabilized hybrids not observed in the centers of domestication. Thus, Brazil can be considered a secondary center of diversification of common bean. A high degree of genome-wide multilocus associations even among unlinked loci was observed, confirming the high level of structure in the sample and suggesting that association mapping should be conducted in separate Andean and Mesoamerican Brazilian samples.     

Origins of the cultivation oflathyrus sativus andL. cicera (fabaceae)

Most of the early and rich archaeobotanical finds ofLathyrus sect.Cicercula, particularly those of the most ancient periods, came from the Balkan peninsula. It has been found that cultivation ofL. sativus began there in the early Neolithic period, around 6000 b.c.e., as a result of the expansion of Near Eastern agriculture of annuals into the region. This, in turn, encouraged development of a greater variety of legumes by the domestication of an additional native species. Similarly, it is suggested that domestication ofL. cicera in southern France and the Iberian peninsula occurred only after the introduction of agriculture into the area. Cultivation of these two closely related species in adjacent regions led to the raising of a mixed crop in many ancient fields. Lathyrus sativus may perhaps be the first crop domesticated in Europe.     

Cordyline ovens (Umu Ti) in Samoa

In ancient Samoa,Cordyline roots were prepared for use as a candy and a sweetening agent by baking in large buried stone ovens for several days. In a modern attempt to duplicate this ancient technology,Cordyline terminalis roots collected in the mountains of Upolu, Western Samoa, were baked in both a modern propane oven and in an oven orumu prepared in the traditional manner. The success of this attempt is described, together with its significance for ethnobotanical and archaeological studies in Samoa.     

Ancient Chinese literature reveals pathways of eggplant domestication

Background and Aims

Changes in key traits occurring during the processes of plant domestication have long been subjects of debate. Only in the case of genetic analysis or with extensive plant remains can specific sets of changes be documented. Historical details of the plant domestication processes are rare and other evidence of morphological change can be difficult to obtain, especially for those vegetables that lack a substantial body of archaeological data. Botanical records chronicled in the ancient literature of established ancient civilizations, such as that of China, are invaluable resources for the study and understanding of the process of plant domestication. Here, the considerable body of ancient Chinese literature is used to explore the domestication process that has occurred with the eggplant (Solanum melongena), an important vegetable in Old World.

Methods

Information about eggplant domestication in the ancient Chinese literature was retrieved using a variety of methods. The information obtained was then sorted by taxon, examined and taxonomic identifications verified.

Key Results

It was found that the earliest record of the eggplant documented in ancient Chinese literature was in a work from 59 bc. As far as is known, this is the earliest reliable and accurately dated record of eggplant in cultivation. The analysis reveals that the process of domestication of the eggplant in China involved three principal aspects of fruit quality: size, shape and taste. These traits were actively and gradually selected; fruit size changed from small to large, taste changed from not palatable to what was termed at the time sweetish, and that over time, a wider variety of fruit shapes was cultivated.

Conclusions

The results indicate that, in addition to data gleaned from archaeology and genetics, evidence as to changes in key traits occurring during the process of plant domestication and selective forces responsible for these changes can be traced through the ancient literature in some civilizations.Key words: Solanum melongena, ancient Chinese literature, domestication process, domestication traits, selective forces     

Variability in Andeannuña common beans (Phaseolus vulgaris,Fabaceae)

Nuñas are a group of common bean (Phaseolus vulgaris, Fabaceae) varieties, whose grains are consumed after toasting in their original Andean habitats. Nowadays, these varieties are restricted to certain parts of the highlands of Peru and Bolivia. Linguistic, ethnobotanical, and archaeological data suggest that they were grown in that zone duringpre-Hispanic times. SDS-PAGE electrophoresis shows a wide range ofphaseolin types amongnuñas, many of which are present in sympatric wild forms. This paper discusses the possibility thatnuñas resulted from an early and widely applied selection pressure during bean domestication in the Andes.     

Plant clock modifications for adapting flowering time to local environments

During and after the domestication of crops from ancestral wild plants, humans selected cultivars that could change their flowering time in response to seasonal daylength. Continuous selection of this trait eventually allowed the introduction of crops into higher or lower latitudes and different climates from the original regions where domestication initiated. In the past two decades, numerous studies have found the causal genes or alleles that change flowering time and have assisted in adapting crop species such as barley (Hordeum vulgare), wheat (Triticum aestivum L.), rice (Oryza sativa L.), pea (Pisum sativum L.), maize (Zea mays spp. mays), and soybean (Glycine max (L.) Merr.) to new environments. This updated review summarizes the genes or alleles that contributed to crop adaptation in different climatic areas. Many of these genes are putative orthologs of Arabidopsis (Arabidopsis thaliana) core clock genes. We also discuss how knowledge of the clock’s molecular functioning can facilitate molecular breeding in the future.

Crop genes that have been implicated in the modulation of photoperiodic flowering time and adaptation include orthologs of Arabidopsis core clock genes.     

Cell wall and protoplast isoperoxidases in relation to injury, indoleacetic Acid, and ethylene effects

A number of plants have been surveyed with respect to isolation by mild grinding in large quantities of leaf cells. The extent of recovery of mesophyll cells per unit leaf area was found to vary with plant species and the method of grinding. Greater than 70% recovery was obtained from the leaves of Canna indica L., Crotalaria Laburnifolia L., and Thunbergia grandiflora Roxb.     

Ethnobotany of chia,Salvia hispanica L. (Lamiaceae)

Salvia hispanica L, was an important staple Mesoamerican food and medicinal plant in pre-Columbian times. Unlike other Mesoamerican pseudocereal crops such asAmaranthus andChenopodium, it has received comparatively little research attention. An ethnobotanical review of this Mesoamerican crop plantSalvia hispanica has been undertaken to examine changes in use accompanying Spanish colonization. A comparative analysis of accounts of use from the 16th century codices of Mexico and subsequent publications has revealed subtle changes in medicinal, culinary, artistic, and religious uses. Several hypotheses surrounding changes in use through time and the original use(s) that led to domestication are developed and tested through collection of ethnobotanical data in the highlands of western Mexico and Guatemala. A general decline in ethnobotanical knowledge associated with wild populations coupled with a loss of habitat in some locations has degraded important germplasm and knowledge resources for a species with great economic potential.     

Multiple origins of the determinate growth habit in domesticated common bean (Phaseolus vulgaris)

Background and Aims

The actual number of domestications of a crop is one of the key questions in domestication studies. Answers to this question have generally been based on relationships between wild progenitors and domesticated descendants determined with anonymous molecular markers. In this study, this question was investigated by determining the number of instances a domestication phenotype had been selected in a crop species. One of the traits that appeared during domestication of common bean (Phaseolus vulgaris) is determinacy, in which stems end with a terminal inflorescence. It has been shown earlier that a homologue of the arabidopsis TFL1 gene – PvTFL1y – controls determinacy in a naturally occurring variation of common bean.

Methods

Sequence variation was analysed for PvTFL1y in a sample of 46 wild and domesticated accessions that included determinate and indeterminate accessions.

Key Results

Indeterminate types – wild and domesticated – showed only synonymous nucleotide substitutions. Determinate types – observed only among domesticated accessions – showed, in addition to synonymous substitutions, non-synonymous substitutions, indels, a putative intron-splicing failure, a retrotransposon insertion and a deletion of the entire locus. The retrotransposon insertion was observed in 70 % of determinate cultivars, in the Americas and elsewhere. Other determinate mutants had a more restricted distribution in the Americas only, either in the Andean or in the Mesoamerican gene pool of common bean.

Conclusions

Although each of the determinacy haplotypes probably does not represent distinct domestication events, they are consistent with the multiple (seven) domestication pattern in the genus Phaseolus. The predominance of determinacy in the Andean gene pool may reflect domestication of common bean prior to maize introduction in the Andes.     

Toxicity of Leaf and Stem Extracts to Tylenchorhynchus dubius

Plant extracts, made by grinding 2 g of fresh tissue in 5 ml of water, were toxic to Tylenchorhynchus dubius and Hoplolaimus spp. Such extracts from leaves and stems of bean (Phaseolus vulgaris L.) and leaves of tobacco (Nicotiana tabacum L.) were most toxic; those from leaves of corn (Zea mays L.), tomato (Lycopersicon esculentum Mill.) and rhododendron (Rhododendron catawbiense L.) were less toxic; and extracts of bean roots were nontoxic. Nematode movement slowed markedly within 1 hr in tobacco leaf extract, and within 4 hr in bean leaf extract; both extracts completely inactivated or killed 95% of the nematodes in 24 hr. Heating leaf extract 10 min at 80 C eliminated toxicity. Absorption of fusicoccin, a phytotoxin produced by Fusicoccum amygdali Del., increased the toxicity of tomato leaf extracts, whereas water extracts of acetone-extracted powder preparations of leaves were about 15-fold more toxic than water extracts of fresh tissue. Addition of homogenized leaves of bean, tobacco and tomato to soil significantly reduced nematode populations within 3 days.     

Patterns of genetic diversity in the Andean gene pool of common bean reveal a candidate domestication gene

Most studies on the genetic diversity of common bean (Phaseolus vulgaris L.) have focussed on accessions from the Mesoamerican gene pool compared to the Andean gene pool. A deeper knowledge of the genetic structure of Argentinian germplasm would enable researchers to determine how the Andean domestication event affected patterns of genetic diversity in domesticated beans and to identify candidates for genes targeted by selection during the evolution of the cultivated common bean. A collection of 116 wild and domesticated accessions representing the diversity of the Andean bean in Argentina was genotyped by means of 114 simple sequence repeat (SSR) markers. Forty-seven Mesoamerican bean accessions and 16 Andean bean accessions representing the diversity of Andean landraces and wild accessions were also included. Using the Bayesian algorithm implemented in the software STRUCTURE we identified five major groups that correspond to Mesoamerican and Argentinian wild accessions and landraces and a group that corresponds to accessions from different Andean and Mesoamerican countries. The neighbour-joining algorithm and principal coordinate clustering analysis confirmed the genetic relationships among accessions observed with the STRUCTURE analysis. Argentinian accessions showed a substantial genetic variation with a considerable number of unique haplotypes and private alleles, suggesting that they may have played an important role in the evolution of the species. The results of statistical analyses aimed at identifying genomic regions with consistent patterns of variation were significant for 35 loci (~20 % of the SSRs used in the Argentinian accessions). One of these loci mapped in or near the genomic region of the glutamate decarboxylase gene. Our data characterize the population structure of the Argentinian germplasm. This information on its diversity will be very valuable for use in introgressing Argentinian genes into commercial varieties because the majority of present-day common bean varieties are of Andean origin.     

Depth-related variation in epiphytic communities growing on the brown alga Lobophora variegata in a Caribbean coral reef

Lobophora variegata is a dominant macroalga on coral reefs across the Caribbean. Over the last two decades, it has expanded its vertical distribution to both shallow and deep reefs along the leeward coast of the island of Cura?ao, Southern Caribbean. However, the ecological implications of this expansion and the role of L. variegata as a living substratum are poorly known. This study compared epiphytic algal communities on L. variegata blades along two depth transects (6?C40?m). The epiphytic community was diverse with a total of 70 species of which 49 were found directly attached to L. variegata. The epiphytic community varied significantly between blade surface, depth and site. The greatest number of genera per blade was found growing on the underside of the blades regardless of site and depth. Filamentous red algae (e.g. Neosiphonia howei) were commonly found on the upperside of the blades over the whole depth gradient, whereas the underside was mainly colonized by calcifying (e.g. Hydrolithon spp., Jania spp., Amphiroa fragillissima), fleshy red algae (e.g. Champia spp., Gelidiopsis spp., Hypnea spinella) and foliose brown alga (e.g. Dictyota spp.). Anotrichum tenue, a red alga capable of overgrowing corals, was a common epiphyte of both blade surfaces. L. variegata plays an important role as a newly available substratum. Thus, its spread may influence other algal species and studies of benthic macroalgae such as L. variegata should also take into consideration their associated epiphytic algal communities.     

Endophytic occupation of peanut root nodules by opportunistic Gammaproteobacteria

Several bacterial isolates were recovered from surface-sterilized root nodules of Arachis hypogaea L. (peanut) plants growing in soils from Córdoba, Argentina. The 16S rDNA sequences of seven fast-growing strains were obtained and the phylogenetic analysis showed that these isolates belonged to the Phylum Proteobacteria, Class Gammaproteobacteria, and included Pseudomonas spp., Enterobacter spp., and Klebsiella spp. After storage, these strains became unable to induce nodule formation in Arachis hypogaea L. plants, but they enhanced plant yield. When the isolates were co-inoculated with an infective Bradyrhizobium strain, they were even found colonizing pre-formed nodules. Analysis of symbiotic genes showed that the nifH gene was only detected for the Klebsiella-like isolates and the nodC gene could not be amplified by PCR or be detected by Southern blotting in any of the isolates. The results obtained support the idea that these isolates are opportunistic bacteria able to colonize nodules induced by rhizobia.     

A survey of outdoor and indoor airborne fungal spora in the Redemption City, Ogun State, south-western Nigeria

The concentration and biodiversity of airborne fungi of the Redemption City, an immense campground for Christian faithful and the temporary site of the Redeemer’s University in south-western Nigeria, was studied between February and May 2011 using the culture plate method. The study was undertaken to assess the concentrations of fungal spores and their health implication in this ever-busy environment. Fifteen different sites classified as closed or open were selected. During the experiment, a total of 228 colonies were counted, and 29 fungal species belonging to 26 genera were isolated which include the following: Aspergillus flavus, Aspergillus niger, Bipolaris spp., Chrysosporium spp., Cladosporium spp., Coniothyrium corda, Curvularia spp., Diplodia spp., Fusarium spp., Gliocladium spp., Monilia spp., Mucor spp., Mucor plumbeus, Penicillium spp., Phycomyces spp., Phytophthora spp., Pilobolus spp., Pyrenochaeta spp., Rhizopus stolonifer, Torula spp., Trichoderma spp. and Trichophyton spp. The most frequently occurring fungi were A. niger, C. corda and M. plumbeus, while the least recorded were Torula and Trichophyton species. Majority of the fungi isolated are known allergens; they could also be opportunistic causing various diseases in man. There is therefore a dire need for good sanitation practices within the studied areas of the camp.     

Ancient DNA from Nubian and Somali wild ass provides insights into donkey ancestry and domestication

Genetic data from extant donkeys (Equus asinus) have revealed two distinct mitochondrial DNA haplogroups, suggestive of two separate domestication events in northeast Africa about 5000 years ago. Without distinct phylogeographic structure in domestic donkey haplogroups and with little information on the genetic makeup of the ancestral African wild ass, however, it has been difficult to identify wild ancestors and geographical origins for the domestic mitochondrial clades. Our analysis of ancient archaeological and historic museum samples provides the first genetic information on the historic Nubian wild ass (Equus africanus africanus), Somali wild ass (Equus africanus somaliensis) and ancient donkey. The results demonstrate that the Nubian wild ass was an ancestor of the first donkey haplogroup. In contrast, the Somali wild ass has considerable mitochondrial divergence from the Nubian wild ass and domestic donkeys. These findings resolve the long-standing issue of the role of the Nubian wild ass in the domestication of the donkey, but raise new questions regarding the second ancestor for the donkey. Our results illustrate the complexity of animal domestication, and have conservation implications for critically endangered Nubian and Somali wild ass.     

Endozoochory of Mediterranean aquatic plant seeds by teal after a period of desiccation: Determinants of seed survival and influence of retention time on germinability and viability

The capacity of eight wetland seeds to be internally dispersed by common teal (Anas crecca L.) after a dry period typical of natural Mediterranean wetlands was experimentally quantified. These plant taxa (Chara spp., Echinochloacrus-galli (L.) P. Beauv., Eleocharis palustris (L.) Roem. & Schult, Polygonum lapathifolium L., Potamogeton nodosus Poir., Potamogeton pusillus L., Schoenoplectus mucronatus (L.) Palla, Scirpus maritimus L.) were frequently ingested by teal in the field. Captive teal were fed with known quantities of dry seeds and faecal samples were collected at intervals of 1-2 h for 48 h. The proportion of seeds retrieved after gut passage that germinated varied between taxa from 3% to 83%. From 2% to 63% of the seeds ingested were recovered intact, and 18-95% of these were still viable. Therefore, an overall 32% of the seeds ingested were evacuated in a viable condition, ranging from 0.2% for Chara spp. to 54% for S. mucronatus. Mean seed retention time was 3-5 h. Overall, 94% of seeds were evacuated within 12 h, but 2% were recovered after more than 24 h. Seed viability was reduced at longer retention times, although viable seeds of all taxa except Chara spp. were recovered 44-48 h after the experiment began. Germinability was increased by gut passage, although for some species this effect was only significant after stratification, indicating that they exhibit both mechanical and physical dormancy. Seed germination was accelerated by gut passage, especially at longer retention times. Gut passage increased the proportion of viable seeds, suggesting selective digestion of non-viable ones. Endozoochorous transport by teal appears to be a widespread dispersal mechanism among wetland plants.