Dioscorea is a genus of great economic value, including important food plants. Fao this publication addresses storage and processing issues of the principal root and tuber crops of the tropics. Setts of water yarn dioscorea alata weighing 75 g each were presprouted in sawdust and then grown in soil. Presently, these species are threatened by genetic erosion due to many factors such as pest attacks and farming practices. Other terms for yam are true yams, greater yam, tropical yam, and name.
The plants were subjected to moisture stress by withholding water from day 15 to 35, or day 36 to 56 or by watering only once every 14 days. Dioscorea batatas is called chinese yam, cinnamon yam, wild yam, or common yam. India is a harbor of biodiversity in general and phytodiversity in particular. Highthroughput sequencing hts methods are increasingly being used in the discovery of new plant viral genomes. The plants database includes the following 30 species of dioscorea. Click below on a thumbnail map or name for species profiles. Dioscorea alata is a plant of the hot humid tropics. The calorific value of all the investigated dioscorea spp. They can be planted 2 to 3 inches deep in 42inch rows with plants spaced 18 inches apart, or in hill plantings 3 feet apart. The dioscorea spp examined included dioscorea rotundata white yam, d.
Of the dioscorea species available in sbr, 10 species are known to be bitter in taste and unpalatable when taken raw. Dioscorea used in chinese medicine with the example of. Yam is the common name applied to plants of about 500 species of the genus dioscorea of the dioscoreaceae family. Several species are widely cultivated in many cultivars including dioscorea alata d. The true yam is about 20 percent starch and as a food is very similar to a potato. To date, several viruses of different genera have been reported to infect yam dioscorea spp.
In an analysis of 4 wild nepalese yam species, including dioscorea bulbifera, bahndari and kawabata 2004 found that constituent chemicals in the yams \tend to imply thatwild yams may present a health hazard potential, which in turn demands propor processing before consumption to eliminate the effects of the antinutrients. Robinson 1987 reported that a diet that meets twothird of the rda recommended dietary allowance values is considered to be adequate for an individual. Yams do well when planted in a hill filled with compost. They are mostly grown for their starchy tubers both cultivated and wild and for medicinal properties. Escambia, gadsden, leon, levy, charlotte, lee, and dade wunderlin et al.
The organisms which cause soft rot of yams dioscorea spp. The longterm storage potential of these tubers is vital for food. Though this effect is weak, it appears to be both time and dosedependent. Dioscorea villosa supplement health benefits, dosage. Experiments were conducted to assess the potential of two gibberellin inhibitors, uniconazolep and prohexadionecalcium, to induce sprouting in tubers from three varieties of d. The 1980 list was based upon the work of the regional committee in southeast asia and its descriptor numbers are given in parentheses beside the present. Fungi associated with soft rot of yams dioscorea spp. Metabolite profiling of dioscorea yam species reveals.
Yam is the common name applied to plants of about 500 species of the genus. Dioscorea is a genus of over 600 species of flowering plants in the family dioscoreaceae, native throughout the tropical and warm temperate regions of the world. Dioscorea batatas is the taxonomic name generally used in the united states29. The common name for the genus, yams, will be used when discussing information applicable to 2 or more of the above species. Treatments of thyroid diseases with chinese herbal medicine and esophageal cancer 5.
By far the most common is dioscorea opposita, for which the rhizome tuber is used. A reliable means to induce sprouting in dormant seed tubers of yams dioscorea species is required to enhance flexibility in planting date and rate of propagation of the crop. Among petroleum ether, ethyl acetate, methanol and 70% ethanol vv extracts of bulbs of d. Complete plastomes of 57 individuals representing all 17 known dioscorea species from west africa were reconstructed. It is a highly invasive plant included in the global compendium of weeds randall, 2012, and which creates. The pdf file linked from each plant community name describes the model and.
It is indigenous to the fujian, guangdong, guangxi, hunan, and zhejiang provinces of china, where it is typically found in forest areas or on disturbed ground beside roads or rivers the species is cultivated in china for food and as use in traditional. The dioscorea genus contains more than 600 species, 14 of which have edible tubers. The relatively reduced complexity of data analysis, ease of operation and higher reproducibility would hopefully facilitate skill transferability, education and capacity building enabling incorporation of. Dioscorea villosa is one of the species of yam referred to as wild yam dioscorea villosa has been claimed to alleviate symptoms of menopause, but there is currently no evidence to support this effect animal evidence suggests dioscorea villosa can increase skin thickness after lowdose supplementation. The pdf file you selected should load here if your web browser has a pdf reader plugin installed for example, a recent version of adobe acrobat reader if you would like more information about how to print, save, and work with pdfs, highwire press provides a helpful frequently asked questions about pdfs alternatively, you can download the pdf file directly to your computer. It covers factors affecting storability, principles of. Five5 towns, kana,kofa gwari, laminga, garaku and kokona in keffi local government area, nasarawa state, nigeria were. In traditional systems of producing yams dioscorea spp. Description dioscorea batatas is a twining herbaceous. Effect of curing treatments on seven key farmers yams. Technical sheet of some wild yam dioscorea species.
In florida, herbarium records now reported for naturalized populations in 7 counties. A study was carried out on the storage rot of yams dioscorea spp in keffi and environs, nasarawa state. It is indigenous to the fujian, guangdong, guangxi, hunan, and zhejiang provinces of china, where it is typically found in forest areas or on disturbed ground beside roads or rivers. Yam is a multi species crop and considered as one of the most important staple food crops of subsaharan africa that provide valuable source of. Effect of culture medium and culture duration on shoot length mm of five yam accessions. Proceeding of the 3rd research planning conference on rootknot nematodes, meloidogyne spp. Species in this genus are dioecious, twining, and herbaceous to woody vines with single or clustered large tubers, some of which are edible and are known as yams acevedorodriguez, 2005. The pdf file you selected should load here if your web browser has a pdf reader plugin installed for example, a recent version of adobe acrobat reader if you would like more information about how to print, save, and work with pdfs, highwire press provides a helpful frequently asked questions about pdfs. Cultivated yams are vegetatively propagated while wild yams are sexually propagated and comprise both diploid. The full diversity of viruses infecting yam, however, remains to be explored. Evolution and phylogenetic diversity of yam species dioscorea. Both of these species originated in southeast asia and very early were carried by voyagers into the western pacific and brought d. Dioscorea species, popularly known as yam worldwide and as ban aalu in odisha, india, is a prime staple medicinalfood substitute for the majority of rural and. This is in the yam family, and the herb is sometimes simply referred to as.
Dike department of animal science and fisheries, imo state university, p. The starches extracted from the tuber of some wild yam species d, praehensilis, d hirtiflora. The tubers of numerous dioscorea yam species are an important. Technical sheet of some wild yam dioscorea species starch. Dioscorea alata has been selected for leaf virus and scorch tolerance among clones. The two most important ones in the pacific are dioscorea alata greater yam, water yam and dioscorea esculenta lesser yam, potato yam. In this study, we employed hts on yam to determine whether any undiscovered. Of these species, chinese yam is the most widely distributed in the united states. Sep 12, 2014 herein we report the promises of dioscorea bulbifera and its bioactive principle, diosgenin as novel.
Journal of applied biosciences african journals online. Herein we report the promises of dioscorea bulbifera and its bioactive principle, diosgenin as novel. The genus dioscorea includes about 350800 species distributed largely in the tropics, but also in warm and temperate regions. Yam traditional pacific island crops research guides. A number of wild crops remain unexplored in this world and among them some have excellent medicinal and nutritional properties. Wilson 80 reported progress made at iita during 19751980 on field selections for resistance to tuber yield reduction by fungal leaf diseases caused by. Faculty of agriculture, delta state university, asaba campus, p. Dioscorea species definition of dioscorea species by the. Lloyd investigated the dioscorea subject, and found that the variety of the vine yielding the drug originally em. United plant savers medicinal plant conservation certificate program. Its growing in shade near a small river in central american rain forest. Experiments were conducted to assess the potential of two gibberellin inhibitors, uniconazolep and prohexadionecalcium, to induce sprouting in tubers from three varieties of. Storage rot of some yams dioscorea spp in keffi and. Comparative analysis of diosgenin in dioscorea species and.
Furthermore, many species are important sources of pharmaceutical precursors. Dioscorea is a genus of flowering plants, and some dioscorea species are known and used as a source for the steroidal sapogenin diosgenin. Effect of partial replacement of yam peel meal dioscorea spp. Presently, these species are threatened by genetic erosion due to many factors.
Thus, although dioscorea was introduced by the thomsonian school in medicine, it became a favorite in the eclectic school, where for decades it has found a cordial reception. Technical sheet of some wild yam dioscorea species starch functional properties sahore drogba alexis1, amani nguessan georges2 1. There are several herbs derived from species of dioscorea used in chinese herb formulas, though only two are used with some frequency. It is considered an effective herb for hyperthyroidism and thyroid cancer. Nwauzor ec, fawole b 1981 root knot nematodes on yams dioscorea spp. Effect of 24epibrassinolide on growth of in vitro shoot. Jun 14, 2018 dioscorea villosa may have effects similar to dehydroepiandrosterone dhea.
The longterm storage potential of these tubers is vital for food security in developing countries. Nutritional and antinutritional evaluation of wild yam. The vast majority of the species are tropical, with only a few species extending into temperate climates. There is no single area, however, where d, alata is the chief starchy food. Dioscorea fordii is a herbaceous vine with oppositely arranged leaves and large, starchy rhizomes which grow vertically into the soil. It is also synonymous with dioscorea oppositifolia. Effect of the acetylation process on native starches of. In storage and the effects of their infection on the nutrient composition nweke, f. Dioscorea sansibarensis pax section macroura, zanzibar yam.
Key access and utilization descriptors for yam genetic resources corporate author. It is named after the ancient greek physician and botanist dioscorides. May 28, 2016 ive never seen this particular dioscorea before. Dioscorea species synonyms, dioscorea species pronunciation, dioscorea species translation, english dictionary definition of dioscorea species. Dioscorea villosa supplement health benefits, dosage, side. However, yam is susceptible to a range of serious and. Evolution and phylogenetic diversity of yam species. There are several species in the genus dioscorea that are known as yams. The plant diversity is distributed from the western ghats to eastern ghats, along with the northeastern region and from the greater himalayas to the plain of ganga. Dioscorea alata water yam dioscorea altissima dunguey. This effect suggests dioscorea villosa is a potentially useful. The fungi enter through wounds and natural openings on the surface of the tubers. However, yam is susceptible to a range of serious and debilitating diseases including viruses.
Dioscorea yams genus dioscorea plant genus a genus of plants dioscoreaceae, family dioscoreaceae, yam family yams yam plant, yam any of a. In parallel, complex taxonomic boundaries in this genus makes it more challenging to properly address the genetic diversity of yam and manage its germplasm. Analysis of biochemical composition of yams dioscorea spp. There are six species that are important staples and these are white yam d. Unfortunately, dioscorea villosa extracts are associated with kidney and liver fibrosis, a condition characterized by excessive scar tissue. Effect of the acetylation process on native starches of yam. To screen potential resource from dioscorea species and related medicinal plants for diosgenin extraction, a rapid method to compare the contents of diosgenin in various plants is crucial.446 546 1419 867 1038 861 7 1600 1647 1166 499 1232 1361 1311 1013 1337 1262 1661 4 1036 1683 1094 309 1214 176 1089 974 1361 350 906 15 416 752 1293 1129 607 551 185 1397 364 16 1432 119 396 15 555 469 278 1225