rdf-syntax-grammar
mods:
  schema location: http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
  title info:
    title: Characterization of maize testing locations in eastern and southern Africa
  name:
    name part: Maideni, Francis W., 1966-
    role:
      role term: creator
  name:
    name part: Betran, Javier F.
    role:
      role term: thesis advisor.
  type of resource: text
  genre: bibliography
  origin info:
    place:
      place term: txu
    date issued: 2006
    issuance: monographic
  language:
    language term: eng
  physical description:
    form: electronic
    form: remote
  abstract: The region of eastern and southern Africa is very diverse in environments and agronomic practices. The region has one of the highest per capita consumption of maize (Zea mays. L), which is predominantly produced by smallholder farmers. Some important constraints facing these farmers include drought and low fertility. For decades, the International Center for Wheat and Maize Improvement (CIMMYT) has been involved in developing maize genotypes that have high grain yields and are tolerant to drought, low fertility and other important constraints. This germplasm is developed for wide adaptation. However, the development of superior germplasm is significantly affected by interaction between genotypes and the environment (i.e., genotype by environment interaction, GEI). To estimate and understand GEI maize genotypes are evaluated in a range of environments representing as much variability of the target growing areas as possible. Because of dwindling resources needed to conduct testing in the region, it may not be possible to test in all potential target areas. Therefore, a careful process of site selection for testing is essential to improve efficiencies in cultivar testing and deployment. The objective of this research was to characterize the maize testing locations of the eastern and southern Africa region. Historical data from CIMMYT Regional Trials from 1999 to2003 was used to characterize the environments and estimate genetic parameters. Environmnent and GEI showed consistently high contributions to the total variation observed among genotypes for grain yield. Environment contributed over 60% and sometimes up to 85% of total variation observed. Sequential retrospective pattern analysis (Seqret) was conducted on the adjusted standardized grain yield. A total of 7 groups of environments were identified. Repeatabilites, a measure of the proportion of phenotypic variation that is due to genetic differences, was reduced under stress conditions. The relationship among trai…
  note: by Francis W. Maideni.
  note: "Major Subject: Plant Breeding"
  note: Title from author supplied metadata (automated record created on Sep. 15, 2006.)
  note: Vita.
  note: Abstract.
  note: Electronic resource.
  note: Mode of access: World Wide Web.
  note: System requirements: World Wide Web access and Adobe Acrobat Reader.
  note: Ph. D. Texas A&M University 2006.
  note: Includes bibliographical references.
  note: Text (Dissertation).
  subject:
    topic: Major plant breeding
  subject:
    topic: genotype by environment interaction
  subject:
    topic: Characterization
  identifier: http://hdl.handle.net/1969.1/3804
  record info:
    record content source: TXA
    record creation date: 061012
    record change date: 20151104080408.0
    record identifier: in00002185565