DOCSLIB.ORG

UK Landrace Conservation Strategy 2

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
UK Landrace Conservation Strategy 2 Landrace conservation strategy for the United Kingdom N. Maxted, M. Scholten, B. Ford-Lloyd, C. Allender, D. Astley, H. Vincent, S.P. Kell and contributors Summary During the last 100 years, European agriculture has undergone a sea change. In the early 1900s, agriculture was mainly based on traditional cultivation systems, where most of the inputs and products (including seed) came from the farm itself; now, the many genetically diverse traditional crop varieties (or landraces) that were once grown by European farmers have been largely replaced by fewer genetically uniform commercially bred cultivars, which now dominate agricultural production. The extent of loss of crop genetic diversity associated with the loss of landraces is difficult to quantify accurately, but we do know that both worldwide and in Europe there has been a massive loss of named landrace varieties that is thought to equate to a significant loss of crop genetic diversity. This erosion of an agrobiodiversity resource that may be critical for future food security has been recognized in a number of international legal instruments, including the Convention on Biological Diversity and the International Treaty on Plant Genetic Resources for Food and Agriculture. As a signatory to these treaties, the UK has an obligation to take steps to secure the full range of its plant genetic resources for food and agriculture, including the diversity of UK landraces. An initial scoping exercises for UK crop landraces indicated that there remains a significant wealth of landrace diversity in the UK but that it is often highly geographically localized and critically threatened with extinction. There the present review focused primarily on landrace diversity in the UK cereal, vegetable and forage crops and current knowledge of in situ landrace maintenance throughout the UK is limited—hence the need for research in this area and the production of a corresponding inventory and conservation strategy. The inventory is needed to provide the baseline data to a) identify conservation needs, b) enact the systematic conservation of landraces in situ and ex situ, c) monitor change (including the assessment of genetic erosion), and d) enhance their use in meeting changing market demands and in promoting UK food security. Landrace data were collated from a wide range of sources, including existing data sets from four UK seedbanks that are central to the maintenance of landrace diversity ex situ, and traditional varieties included in the UK National Lists of Varieties, ‘B’ List. Other data were collated following media releases and advertisements and by using a questionnaire, internet searches, email correspondence, telephone calls and face to face meetings, capturing a broad range of interest groups, companies and individuals. Results of analysis of seedbank data do not yet reflect the full range of UK landrace diversity available in ex situ collections maintained in the UK, mainly because a proportion of landrace germplasm is not yet recognized in the seedbank information management systems. Nonetheless, the analysis is an important first step in the process of consolidating ex situ collections data for inclusion in the UK landrace inventory. ‘B’ List varieties collectively form another important component of the inventory; there may be challenges in the future in keeping this part of the inventory of in situ maintained material updated due to a dependency on data provision by a number of commercial companies who are the official maintainers of a large proportion of the varieties. The project identified and created an inventory of 67 wheat, barley and oats, 569 English and Welsh vegetables and 7 forage landrace populations. A number of key in situ maintainers of UK landrace diversity have been identified and these include commercial seed companies, non-governmental organizations, individual farmers, allotment-holders and home gardeners. Critically, this research has highlighted the fact that while the genetic diversity of our crops may have been impoverished through the loss of many traditional varieties in the past—diversity that is irreplaceable—new variation is currently being created through grower-based breeding. This may be as a result of deliberate or passive variety improvement through repeated cycles of selection and seed-saving or occasionally through accidental or deliberate cross-pollination leading to the production of a new variety. Therefore, while the loss of old varieties and the diversity that has gone with them is of concern, and recognizing that any new variation will not replace what has been lost, it is important PGR Secure Deliverable 4.3: UK landrace conservation strategy 2 to acknowledge that we may now be in a new period of expansion of locally-based crop diversity and therefore need to put in place strategies to capture this diversity and nurture the culture that is responsible for creating and maintaining it. The study concludes with a number of recommended actions that will be necessary to secure the diversity of UK landraces as an agrobiodiversity resource critical for future food security, as well as a vital component of our biodiversity and cultural heritage. In summary these are: Establish and maintain a comprehensive inventory of UK landraces; Improve and standardize the management of landrace data; Establish and maintain a list of landrace maintainers and key contacts; Open and maintain dialogue with key groups and individuals; Initiate a landrace protection scheme in England and Wales; Enhance ex situ landrace collections; Stimulate landrace use by plant breeders; Carry out research into landrace diversity in the context of climate change; Educate and raise public awareness of local landrace diversity; Review opportunities for supporting landrace cultivation through policy and legislative instruments. Acknowledgements The research presented here has involved many individuals from a diverse range of organizations, as well as independent contacts. The authors are indebted to the following people who have supported this work with ideas, advice, data, contacts and practical assistance, all of which have made this research possible. We would like to express our particular gratitude to Niall Green and George Campbell (SASA), Mike Ambrose (JIC), Neil Munro (Garden Organic) and Jack Edgley (Defra) for their expert advice and for provision of access to data. Although this report has been produced under the umbrella of the PGR Secure project, no funding was available within the project to complete the work reported. The research was funded by the UK Department for Environment, Food and Rural Affairs (Defra). PGR Secure Deliverable 4.3: UK landrace conservation strategy 3 Contents Summary ................................................................................................................................................. 2 Acknowledgements ................................................................................................................................. 3 Contents .................................................................................................................................................. 4 1. Introduction ................................................................................................................................... 6 1.1 The importance of landrace diversity for UK agriculture and food security .......................... 6 1.2 The causes and consequences of loss of crop genetic diversity ............................................. 7 1.3 The global response to crop genetic erosion and national obligations .................................. 9 1.4 Landrace conservation and use in the UK: current state of the art ...................................... 10 1.5 Project objectives .................................................................................................................. 14 2. Methodology ................................................................................................................................ 14 2.1 Experts’ meeting ................................................................................................................... 15 2.2 Scope of the inventory—defining ‘landrace’ ........................................................................ 15 2.3 Designing the landrace database: descriptors and structure ............................................... 16 2.4 Strategy for accessing landrace information ........................................................................ 17 3. Cereal Inventory ........................................................................................................................... 22 3.1 Background ........................................................................................................................... 22 3.2 Cereal landraces in mainland Great Britain .......................................................................... 27 3.3 Extant cereal landraces on the Inner Hebrides ..................................................................... 28 3.4 Extant cereal landraces on the Outer Hebrides .................................................................... 31 3.5 Extant cereal landraces on Orkney and the Shetland Islands ............................................... 33 3.6 Avena strigosa: a threatened species ................................................................................... 35 3.7 Cereal research needs ..........................................................................................................
Load more

Recommended publications
  • Identification of Cereal Remains from Archaeological Sites 2Nd Edition 2006
    Identification of cereal remains from archaeological sites 2nd edition 2006 Spikelet fork of the “new glume wheat” (Jones et al. 2000) Stefanie JACOMET and collaborators Archaeobotany Lab IPAS, Basel University English translation partly by James Greig CEREALS: CEREALIA Fam. Poaceae /Gramineae (Grasses) Systematics and Taxonomy All cereal species belong botanically (taxonomically) to the large family of the Gramineae (Poaceae). This is one of the largest Angiosperm families with >10 000 different species. In the following the systematics for some of the most imporant taxa is shown: class: Monocotyledoneae order: Poales familiy: Poaceae (= Gramineae) (Süssgräser) subfamily: Pooideae Tribus: Triticeae Subtribus: Triticinae genera: Triticum (Weizen, wheat); Aegilops ; Hordeum (Gerste; barley); Elymus; Hordelymus; Agropyron; Secale (Roggen, rye) Note : Avena and the millets belong to other Tribus. The identification of prehistoric cereal remains assumes understanding of different subject areas in botany. These are mainly morphology and anatomy, but also phylogeny and evolution (and today, also genetics). Since most of the cereal species are treated as domesticated plants, many different forms such as subspecies, varieties, and forms appear inside the genus and species (see table below). In domesticates the taxonomical category of variety is also called “sort” (lat. cultivar, abbreviated: cv.). This refers to a variety which evolved through breeding. Cultivar is the lowest taxonomic rank in the domesticated plants. Occasionally, cultivars are also called races: e.g. landraces evolved through genetic isolation, under local environmental conditions whereas „high-breed-races“ were breed by strong selection of humans. Anyhow: The morphological delimitation of cultivars is difficult, sometimes even impossible. It needs great experience and very detailed morphological knowledge.
    [Show full text]
  • Epidemiology of Rabies
    How to cite: Putra, K. S. A. (2018). Epidemiology of rabies. International Journal of Chemical & Material Sciences, 1(1), 14-24. https://doi.org/10.31295/ijcms.v1n1.4 Epidemiology of Rabies Ketut Santhia Adhy Putra Independent Research of Zoonotic Diseases Ex. coordinator of Virology Laboratory, BBVet Denpasar, Directorate General of Livestock and Animal Health, Ministry of Agriculture, Jakarta [email protected] / [email protected] Abstract The occurrence of an outbreak of rabies in Bali as a shock to the people and local governments are instantly becoming the world's attention because of Bali as a world tourism destination. Since the first outbreak in the southern peninsula of Bali in November 2008, rabies quickly spread across the districts/municipality, until July 2015 had spread across 54 subdistricts and 263 villages. The proportion of rabies cases in the subdistricts and villages the highest occurred in 2011 is shown 94.7% and 36.7%, respectively, but its spread dropped dramatically in 2013 only occurred in 23 subdistricts (40.4%) and 38 villages (4,2%), though rabies outbreak back by increasing the number and distribution of rabies cases significantly in 2014, spread over 94 villages even until July 2015 spread over 89 villages. Rabies attacks the various breeds of dogs with the proportion of rabies in the local dogs showed the highest (98.44%), as well as the male dog, is very significantly higher than female dogs. By age group, the proportion seen in the age group of 1 to 2 years showed the highest (39.9%). Other animals, such as cats, cows, goats, and pigs have also contracted the rabies infected dog bitesthe.
    [Show full text]
  • Investigation of the Origin of the Avenacin Gene Cluster for Synthesis of Defense Compounds in Oats
    Adaptive metabolic gene clusters as toolkits for chemical innovation: Investigation of the origin of the avenacin gene cluster for synthesis of defense compounds in oats Hoi Yee Chu (Athena) A thesis submitted to the University of East Anglia for the degree of Doctor of Philosophy University of East Anglia John Innes Centre Norwich, the United Kingdoms September 2013 c This copy of the thesis has been supplied on condition that anyone who consults it is understood to recognise that its copyright rests with the author and that use of any information derived there-from must be in accordance with current UK Copyright Law. In addition, any quotation or extract must include full attribution. Abstract Operon-like gene clusters are functional cassettes of physically linked and non-homologous genes involved in the same pathway. To date, 20 such plant gene clusters have been discovered, all of which are involved in specialised metabolism. Plant gene clusters raise interesting biological questions about their importance and the drivers behind their formation. This thesis describes the investigation of the evolution of the avenacin gene cluster, discovered in the diploid oat Avena strigosa S75, via wet-bench experiments and bioinformatic analyses, commencing with the general introduction (Chapter 1). Chapter 2 to 4 describe the survey on the avenacin production, expression pattern and phylogeny of the five characterized avenacin biosynthetic (Sad) genes within Aveninae, focusing on Avena L. The genomes of all Avena spp. investigated, including the avenacin deficient A. longiglumis, possess the five Sad gene homologues. The expression pattern of the Sad gene homolgoues vary in a genome-type dependent manner that it is root-specific amongst A genome oats.
    [Show full text]
  • Recent Advances in Animal Welfare Science VI
    Recent advances in animal welfare science VI UFAW Animal Welfare Conference 28th June 2018 Centre for Life, Newcastle upon Tyne, UK #UFAWNCL18 Welcome to the UFAW Conference The science of animal welfare is a cross-disciplinary field of research that aims to provide a sound basis on which to build guidance and find solutions to the challenges raised by our caring for and interactions with both kept and wild animals. As part of its on-going commitment to improving animal welfare through increased scientific understanding, UFAW is holding this, the sixth of our on-going series of one day conferences, to consider ‘Recent advances in animal welfare science’. These conferences are intended to provide a platform at which both established animal welfare scientists and those beginning their careers can discuss their work and a forum at which the broader community of scientists, veterinarians and others concerned with animal welfare can come together to share knowledge and practice, discuss advances and exchange ideas and views. We hope that it achieves these aims and fosters links between individuals and within the community. We would like to thank all those who are contributing to the meeting, as speakers, poster presenters and chairs, as well as the delegates from the many countries who are attending. We look forward to what we trust will be a thought-provoking and engaging meeting. Stephen Wickens, Robert Hubrecht and Huw Golledge UFAW 2 The International Animal Welfare Science Society Registered Charity No 207996 (Registered in England) and Company Limited by Guarantee No 579991 General Information Organisers The Universities Federation for Animal Welfare (UFAW) is an independent registered charity that works with the animal welfare science community worldwide to develop and promote improvements in the welfare of farm, companion, laboratory, captive wild animals and those with which we interact in the wild, through scientific and educational activity.
    [Show full text]
  • The Effect of Stress on Livestock and Meat Quality Prior to and During Slaughter
    WellBeing International WBI Studies Repository 1980 The Effect of Stress on Livestock and Meat Quality Prior to and During Slaughter Temple Grandin Grandin Livestock Handling Systems Follow this and additional works at: https://www.wellbeingintlstudiesrepository.org/acwp_faafp Part of the Agribusiness Commons, Animal Studies Commons, and the Operations and Supply Chain Management Commons Recommended Citation Grandin, T. (1980). The effect of stress on livestock and meat quality prior to and during slaughter. International Journal for the Study of Animal Problems, 1(5), 313-337. This material is brought to you for free and open access by WellBeing International. It has been accepted for inclusion by an authorized administrator of the WBI Studies Repository. For more information, please contact [email protected]. REVIEW ARTICLE THE USE OF ANIMALS IN The Effect of Stress on HIGH SCHOOL BIOLOGY CLASSES AND SCIENCE FAIRS Livestock and Meat Quality Edikd i-!paihP!' ~aw:it> Bril\' rd·.·:.· Prior to and During Slaughter A Temple Grandin* NEW RESOURCE Abstract FOR The effects of stress on cattle, pigs and sheep prior to slaughter are reviewed. Long-term preslaughter stress, such as fighting, cold weather, fasting and transit, BIOLOGY which occurs 12 to 48 hours prior to slaughter depletes muscle glycogen, resulting in meat which has a higher pH, darker color, and is drier. Short-term acute stress, such as excitement or fighting immediately prior to slaughter, produced lactic acid EDUCATION from the breakdown of glycogen. This results in meat which has a lower pH, lighter color, reduced water binding capacity, and is possibly tougher. Psychological stressors, such as excitement and fighting, will often have a more detrimental ef­ ANIMALS IN EDUCATION explores the scien­ • What approach to live animal projects fect on meat quality than physical stressors, such as fasting or cold weather.
    [Show full text]
  • Avena Strigosa Schreb.) Germplasm
    EVALUATION OF BLACK OAT ( AVENA STRIGOSA SCHREB.) GERMPLASM Except where reference is made to the work of others, the work described in this thesis is my own or was done in collaboration with my advisory committee. This thesis does not include proprietary or classified information. ________________________________________ Thomas Antony Certificate of Approval: _________________________ _________________________ David B. Weaver Edzard van Santen, Chair Professor Professor Agronomy and Soils Agronomy and Soils _______________________ _________________________ Andrew J. Price Joe F. Pittman Assistant Professor Interim Dean Agronomy and Soils Graduate School EVALUATION OF BLACK OAT ( AVENA STRIGOSA SCHREB.) GERMPLASM Thomas Antony A Thesis Submitted to the Graduate Faculty of Auburn University in Partial Fulfillment of the Requirement for the Degree of Master of Science Auburn, Alabama December 17, 2007 EVALUATION OF BLACK OAT ( AVENA STRIGOSA SCHREB.) GERMPLASM Thomas Antony Permission is granted to Auburn University to make copies of this thesis at its discretion, upon the request of individuals or institutions and at their expense. The author reserves all publication rights. ___________________________________ Signature of Author ___________________________________ Date of Graduation iii THESIS ABSTRACT EVALUATION OF BLACK OAT ( AVENA STRIGOSA SCHREB.) GERMPLASM Thomas Antony Master of Science, December 17, 2007 (B.S. (Agriculture), Kerala Agricultural University, India, 2002) (B.S. (Botany), Mahatma Gandhi University, India, 1995) 156 Typed Pages Directed by Edzard van Santen Black oat has become an important winter cover crop in subtropical and temperate regions. Originating in the northern parts of Spain and Portugal, black oat cultivation has spread to different parts of the globe. Even though different in ploidy level, diploid black oat has been used in many hexaploid common oat ( A.
    [Show full text]
  • Innovative Garments for Preservation of Sheep Landraces in Italy
    animals Article New Value to Wool: Innovative Garments for Preservation of Sheep Landraces in Italy Ruggiero Sardaro * and Piermichele La Sala Department of Economics, University of Foggia, 71121 Foggia, Italy; [email protected] * Correspondence: [email protected] Simple Summary: Animal landraces are historic local breeds often characterized by low production levels, so that their economic sustainability is often threatened and the risk of extinction is high. In Basilicata, southern Italy, a sheep landrace jeopardized of extinction is Gentile di Puglia. Thus, the study aimed at investigating the feasibility of a possible conservation strategy for such landrace based on the innovative use of its wool for the production of quality garments, so as to give new value to wool and allow further income to farmers. The results highlighted a possible good demand for such products, so as to reduce the difference in gross margin between Gentile di Puglia and the standardized intensively-farmed Comisana, from 57% to 3%. Such economic performance could be further improved by widening the set of fashion wool garments produced, so as to make the Gentile di Puglia even more preferable than other high-production breeds. Abstract: In Basilicata, southern Italy, a sheep landrace jeopardized of extinction is Gentile di Puglia due to low production levels, low market values of milk and meat, and replacement of wool with synthetic fibers. Due to these dynamics farmers progressively resort to intensive breeding systems, hence causing the gradual disappearance of the ovine sector, the withering of traditional breeding Citation: Sardaro, R.; La Sala, P. New culture and the abandonment of internal and marginal territories.
    [Show full text]
  • A Multilevel Exploration of Avena Strigosa Diversity As a Prelude To
    Podyma et al. BMC Plant Biology (2019) 19:291 https://doi.org/10.1186/s12870-019-1819-6 RESEARCH ARTICLE Open Access A multilevel exploration of Avena strigosa diversity as a prelude to promote alternative crop Wiesław Podyma1,2 , Paulina Bolc1 , Joanna Nocen1 , Marta Puchta1 , Sylwia Wlodarczyk1 , Boguslaw Lapinski1 and Maja Boczkowska1,2* Abstract Background: Sand oat (Avena strigosa Schreb.), one of the four cultivated species of the genus Avena, could be considered as another alternative crop. In gene banks 865 germplasm samples of this species have been preserved that have not been thoroughly investigated so far. The results of phenotyping (36 traits), isoenzymatic (12 systems) and genetic (8 pairs of Sequence-related amplified polymorphism markers) variation were used to obtain the complete description of 56 accessions diversity originated from different parts of world. Results: Breeded and weedy forms represented similar pool of morphological traits that indicated a short-term and extensive breeding process, albeit all accessions which we classified as cultivated were characterized by better grain and green mass parameters compared to the weedy ones. Isoenzymes showed relationships with geographical origin, which was not possible to detect by SRAP markers. There was no similarity between morphological and biochemical results. The polymorphism level of SRAP markers was lower than indicated by the available literature data for other species, however it may result from the analysis of pooled samples of accessions with a high internal variability. The extensive type of breeding and its relatively short duration was also reflected in the population structure results. Joint analysis revealed that a secondary centre of diversity is being created in South America and that it has its genealogy from the Iberian Peninsula.
    [Show full text]
  • BLACK OATS (Avena Strigosa)
    Cover Crop Information Sheet BLACK OATS (Avena strigosa) True black oats (Avena strigosa) are a different species than oats (Avena sativa) usually planted in the Coastal Plain. They produce a dense, thick growth and will produce comparable biomass to cereal rye at half to 2/3 the height. They are less cold tolerant than common oats. There are two varieties of black oat available for sale in the U.S. – “SoilSaver” and “Pratex”. Seeds for SoilSaver are not currently commercially available due to seed crop failure. Recommended Varieties Variety Reasons Why Source SoilSaver Increased cold tolerance. USDA Black Oats Plant Guide Planting Information Information Comments Source Drilled Seed 1 - 1 ½ USDA Black Oats Plant Guide Depth (inches) Drilled Seeding 50 - 70 Managing Cover Crops Rate (lbs/acre) Profitably, USDA Black Oats Plant Guide Broadcast 100 USDA Black Oats Plant Guide Seeding Rate (lbs/acre) Aerial Seeding N/A Rate (lbs/acre) Termination Information Information Source Black oats are not as cold hardy as most oat varieties. They will usually winter kill USDA Black Oats Plant Guide at less than 19F depending on growth stage. SoilSaver was developed to be more cold tolerant. Black oats can be terminated by herbicides, rolling & crimping, mowing, and tillage. They can be killed by rolling & crimping alone at the early milk stage. Rolling & crimping should be combined with herbicides at earlier growth stages. Consult your local Extension and state Pest Management Handbook for herbicide recommendations. Always follow the herbicide label. Continue to next page… southerncovercrops.org 1 Cover Crop Information Sheet BLACK OATS (Avena strigosa) Cultural Traits Traits Comments Source Typical Dry 4,000 - 7,000 USDA Black Oats Plant Guide Matter Range (lbs/acre) Typical Total N 15 - 30 Unpublished Literature Review Range (lbs/acre) in Coastal Plain – Gaskin Life Cycle Cool season USDA Black Oats Plant Guide annual grain Growth Habit Upright USDA Black Oats Plant Guide Preferred Soil pH 4.5 - 7.3 USDA Black Oats Plant Guide Relative Seed N/A Currently not available.
    [Show full text]
  • Genetic Control of Immune Response to Pseudorabies and Atrophic Rhinitis Vaccines: I
    Animal Science Publications Animal Science 1987 Genetic Control of Immune Response to Pseudorabies and Atrophic Rhinitis Vaccines: I. Heterosis, General Combining Ability and Relationship to Growth and Backfat David Lynn Meeker Iowa State University Max F. Rothschild Iowa State University, [email protected] L. L. Christian Iowa State University C. M. Warner Iowa State University Follow this and additional works at: http://lib.dr.iastate.edu/ans_pubs H. TP. aHrti lofl the Agriculture Commons, Animal Sciences Commons, Biochemistry, Biophysics, and SIotrwauctur Stateal U nBivioerlositgy y Commons, Genetics Commons, and the Veterinary Medicine Commons The ompc lete bibliographic information for this item can be found at http://lib.dr.iastate.edu/ ans_pubs/318. For information on how to cite this item, please visit http://lib.dr.iastate.edu/ howtocite.html. This Article is brought to you for free and open access by the Animal Science at Iowa State University Digital Repository. It has been accepted for inclusion in Animal Science Publications by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Genetic Control of Immune Response to Pseudorabies and Atrophic Rhinitis Vaccines: I. Heterosis, General Combining Ability and Relationship to Growth and Backfat Abstract Data from 988 pigs from 119 litters farrowed in two seasons of a three-breed diallel crossbreeding experiment were analyzed to estimate general combining abilities of breeds and heterosis for humoral immune response to pseudorabies virus and atrophic rhinitis vaccines. Twenty purebred boars and 85 sows of the Duroc, Landrace and Yorkshire breeds were mated to provide the nine breed-of-sire and breed-of-dam combinations.
    [Show full text]
  • Physilogical and Biochemical Responses of Avena Species To
    Vol. 12(43), pp. 6170-6175, 23 October, 2013 DOI: 10.5897/AJB12.1044 ISSN 1684-5315 ©2013 Academic Journals African Journal of Biotechnology http://www.academicjournals.org/AJB Full Length Research Paper Studies on morpho-physiological characters of different Avena species under stress conditions H. C. Pandey1*, M. J. Baig2, Shahid Ahmed1, Vikas Kumar1 and Praveen Singh3 1Indian Grassland and Fodder Research Institute, Jhansi-284003, Uttar Pradesh, India. 2Central Rice Research Institute, Cuttack, Orrisa, India. 3SKUAST-J, Poonch-185101. Jammu & Kashmir. India Accepted 12 April, 2013 Seven species of oat (Avena) were evaluated for their relative drought tolerance under soil moisture stress. The plant height, leaf area production and biomass yield reduced under soil moisture stress. Among the species tested, minimum reduction in height was recorded in Avena vaviloviana, Avena abyssinica and Avena sterilis at vegetative and flowering stages. Significant decrease in leaf area production was recorded at vegetative stage, whereas at flowering stage, the decrease in leaf area production was marginal in A. sterilis followed by A. abyssinica predicting their more adaption to stress environment. The increase in specific leaf weight (SLW) of all the species of Avena showed increase in leaf thickness, exhibiting high water retention capacity under soil moisture stress condition which is a requisite trait for drought tolerance. Soil moisture stress imposed at vegetative and flowering stages reduced fresh biomass yield in all the species. Minimum reduction in dry biomass accumulation under stress environment at vegetative stage was recorded in A. sterilis followed by A. strigosa and A. sativa, exhibiting their tolerance to drought at early stages of growth.
    [Show full text]
  • Meiotic Studies of Some Avena Species and Populations in Iran
    Journal of Sciences, Islamic Republic of Iran 14(2): 121-131 (2003) University of Tehran, ISSN 1016-1104 MEIOTIC STUDIES OF SOME AVENA SPECIES AND POPULATIONS IN IRAN M. Sheidai*, P. Koobaz, and B. Zehzad Department of Biology, Faculty of Science, Shahid Beheshti University, Tehran, Islamic Republic of Iran Abstract Eleven populations of five Avena species were analysed for meiotic characters including chiasma frequency and distribution as well as chromosomal association and segregation. Plants of a single population of A. eriantha showed the presence of 2n = 14 (diploid) and 2n = 4x = 28 chromosome number. Populations of A. barbata and A. wiestii possessed n = 14, while populations of A. sterilis ssp. ludoviciana possessed 2n = 6x = 42 (hexaploid) chromosome number. Tetraploid and hexaploid species showed diplontic behavior and formed only bivalents. The species and populations studied differed significantly in the frequency of chiasmata. B-chromosomes occurred in some of the species studied. Cytomixis and chromosome elimination led to aneuploid and unreduced pollen mother cell formation in the species studied. Keywords: Avena; B-chromosomes; Chiasma frequency; Cytomixis study considers the meiotic analysis of some Avena Introduction species/populations in Iran trying to reveal the ploidy The genus Avena L. (Tribe Aveneae) comprises level and the basic cytogenetic information of these about 27 species throughout the world [3], out of which species for the first time. 9 or 10 species occur in Iran [4,18]. These species are considered as important range grasses of Iran and grow Materials and Methods wild throughout the country. All Avena species are inbreeders and annuals with Plant Material the exception of A.
    [Show full text]