Time filter

Source Type

Cincinnati, OH, United States

Rivera D.,University of Murcia | Obon C.,University Miguel Hernandez | Garcia-Arteaga J.,University Miguel Hernandez | Egea T.,University Miguel Hernandez | And 7 more authors.
Botanical Journal of the Linnean Society | Year: 2014

The main purpose of this study was, first, to analyse the morphology of seeds of Phoenix spp. and relevant cultivars and to assess the taxonomic value of the information generated as a means of studying the systematics and evolutionary history of the genus Phoenix. We then analysed seed morphological diversity in P.dactylifera, supported by morphotypes shared with fossil and/or archaeological materials, to advance the knowledge of the origins, history and biogeography of one of the most important cultivated palm species. The other objective was to develop a methodology for assigning different commercial seed samples and archaeological materials to determined morphotypes as a tool for their identification at the species level. Three hundred and sixty-four seed samples (3920 seeds) were analysed: 304 samples of modern Phoenix spp. (including five herbarium type specimens and eight type icons), 51 archaeological samples and nine fossil seed samples and subsamples. Information was systematized in a crude matrix with 364 units representing seed samples and 67 descriptors. Descriptors are frequencies, in percentage, for each of the 41 qualitative states and of the 26 classes that were recognized for the quantitative parameters. Analyses proceeded sequentially, starting with modern samples consisting of type specimens and botanically verified specimens. Eight species show characteristic seeds and are clearly assigned to morphotypes [P.acaulis, P.canariensis s.s., P.paludosa, P.reclinata, P.roebelenii, P.rupicola, P.sylvestris and P.theophrasti (excluding populations from Datça, Turkey)]; the other taxa are not clearly separated on the basis of the seed morphology alone. In parallel, fossil and archaeobotanical samples were analysed. There is no clear separation between fossil and archaeological samples, between different periods of the archaeological samples or geographical origins. Combination of modern, fossil and archaeological seed results in the same analysis revealed that it is possible to allocate archaeological and fossil materials to morphotypes shared with modern living Phoenix spp. All archaeobotanical samples could be classified in groups with modern seed samples. The assignment of archaeobotanical samples was made, mainly, to morphotypes of P.dactylifera. However, some samples were assigned to morphotypes of P.reclinata, P.caespitosa, P.atlantica, P.theophrasti, P.pusilla and P.canariensis. Archaeological seeds were not allocated to group19, containing the samples of P.sylvestris, P.iberica and the Miocene fossil P.bohemica. It appears that species such as P.theophrasti, P.canariensis, P.caespitosa and P.reclinata formerly had a much wider area of distribution. The morphology of two of the three Eocene samples (Phoenicites occidentalis and Phoenix hercynica) is that of P.dactylifera. Attribution and dating of these samples need to be carefully reviewed. Apparently the great diversity of P.dactylifera date morphotypes during the Neolithic was followed, during the Chalcolithic and the Bronze Age, by a remarkable constriction (bottleneck) in terms of morphological variability, which slowly recovered from the Iron Age onwards. With the currently available evidence, we cannot exclude a group ancestral to P.dactylifera in the Persian Gulf, related to the eastern chlorotype. In parallel, another group ancestral to P.dactylifera may exist in the western Mediterranean, including P.iberica, related to the western chlorotype. © 2014 The Linnean Society of London. Source

Johnson D.V.,3726 Middlebrook Ave
Emirates Journal of Food and Agriculture | Year: 2014

Periodic international meetings of date palm scientists to present the results of new research and technologies have advanced the development of modern date palm propagation, farming practices, fruit production and processing, as well as biotechnology and molecular marker technology. From the first such event in Algeria in 1931, to the recent one in Saudi Arabia in 2011, a total of 35 international meetings have been held in 14 countries during the eight decades. Most commonly referred to as a conference or a symposium, these meetings have been organized around specific date palm themes, and in most cases a proceedings has been published. As an aid to date palm researchers, this bibliographic study attempts to summarize information about the time, place, general subject matters and publications generated by these meetings. Source

Johnson D.V.,3726 Middlebrook Ave
Emirates Journal of Food and Agriculture | Year: 2012

Multipurpose palm species development would benefit from a broader consideration of the varied economic products palms can potentially provide. All economic palm species have a primary product which accounts for their exploitation or domestication and industrialization. A nearly-exclusive emphasis on the primary product has often obscured the potential value of secondary products. Responsible disposal of residues from harvesting and processing of primary palm products often has the potential of being transformed from a disposal expense and potential source of environmental pollutants into secondary products of value. Examples from other palms which may have applicability to date palm production include: 1) In the oil palm industry, empty palm oil fruit bunches are used as fuel to generate electrical energy and yield a fine ash with industrial uses. 2) In coconut plantation operations, pruned leaves and unwanted husks can be used as fertilizer for the plantation or burned to generate energy. 3) Replacement of ageing plantation trees provides an abundance of woody material requiring disposal, affording a periodic opportunity for innovative secondary product harvest. Technical research on the utilization of palm by-products is typically focused on an individual species, but the results often have broad potential adoption for other economic palms. Source

Johnson D.V.,3726 Middlebrook Ave
Emirates Journal of Food and Agriculture | Year: 2016

The date palm tree has hundreds of uses, many products supplying desert dwellers with resources not elsewhere available in nature. Insufficient information is known about the numerous minor ethnobotanical uses of the date palm. This study is concerned with unusual examples from the multiple reported uses of seeds, empty fruit stalks and leaf midribs, and their transformation into prayer beads, walking sticks and fishing boats, respectively. A better appreciation of the overall commercial and subsistence values of the date palm tree enhances justification for its further development in the broadest sense. Source

Johnson D.V.,3726 Middlebrook Ave | Al-Khayri J.M.,King Faisal University | Jain S.M.,University of Helsinki
Emirates Journal of Food and Agriculture | Year: 2013

An accelerating worldwide trend toward planting elite cultivars is leading to genetic erosion and a narrowing of the gene pool upon which the date-palm industry is based. Large numbers of seedling dates are known in many major date-growing countries, as well as in naturalized populations in Spain and the Americas where the palm was intentionally introduced. Seedling dates growing under different climatic conditions from those of the major production areas represent potential genetic resources that should be evaluated for desirable traits. Utilizing modern biotechnology, traits such as disease and pest resistance, hardiness, tolerance of salty soils and improved fruit quality and quantity potentially can be transferred to elite cultivars to sustain and further improve fruit production. Specific examples of important seedling date palm populations in Spain, Peru and Mexico are discussed, as well as new cultivars derived from seedlings in the United States. Research on seedling date populations is recommended, along with the establishment of ex situ germplasm collections of promising specimens as living plants, cold storage of seeds or cryopreservation. Source

Discover hidden collaborations