Blog
About

  • Record: found
  • Abstract: found
  • Article: found
Is Open Access

Evaluation of maize core collection for drought tolerance Translated title: Avaliação da coleção núcleo de milho quanto à tolerância à seca

Read this article at

Bookmark
      There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

      Abstract

      The maize genebank (GBmaize) preserves nearly 4,000 accessions for conservation and use. The use is however restricted because the accessions do not perform as well as the elite genotypes. This problem can be reduced by pre-breeding, i.e., by extending the information on germplasm and introgressing useful alleles. Since irregular rainfall distribution and drought induce maize yield losses, drought tolerance is a main breeding target. In this study, the GBmaize accessions were evaluated for drought tolerance. Environmental factors, genotypes and the respective interactions influence the phenotypic expression. There was however no interaction genotype - irrigation level, so no accessions with different performance under the two water regimes could be identified. The performance of the following accessions was promising for a number of traits: SP154, BA166, MG099, CE002, SE025, BA154, BA194, BA085, MG076, PR053, Roxo Macapá, SE016, and AL018.

      Translated abstract

      O banco de germoplasma de milho (BGMilho) preserva quase 4000 acessos visando conservação e uso. Entretanto, esse uso é reduzido, pois seus acessos apresentam desempenho inferior aos genótipos elite. O pré-melhoramento visa contornar esse problema, ampliando a informação sobre o germoplasma e introgredindo alelos úteis. A má distribuição de chuvas e a seca levam a perdas de produção de milho, o que faz com que a tolerância à seca seja uma das prioridades do melhoramento.Neste trabalho, foram avaliados acessos do BGMilho quanto à tolerância à seca. Fatores ambientais, genotípicos e suas interações influenciaram a manifestação fenotípica, entretanto a interação entre genótipos e regimes de irrigação esteve ausente, levando a não identificação de acessos com comportamento diferenciado nas duas condições hídricas. Os seguintes acessos foram destacados devido ao comportamento superior para vários caracteres: SP154, BA166, MG099, CE002, SE025, BA154, BA194, BA085, MG076, PR053, Roxo Macapá, SE016 e AL018.

      Related collections

      Most cited references 19

      • Record: found
      • Abstract: found
      • Article: not found

      Molecular and physiological approaches to maize improvement for drought tolerance.

      Average maize yields have increased steadily over the years in the USA and yet the variations in harvestable yield have also markedly increased. Much of the increase in yield variability can be attributed to (1) varying environmental stress conditions; (2) improved nitrogen inputs and better weed control; and (3) continuing sensitivity of different maize lines to the variation in input supply, especially rainfall. Drought stress alone can account for a significant percentage of average yield losses. Yet despite variable environments, new commercially available maize hybrids continue to be produced each year with ever-increasing harvestable yield. Since many factors contribute to high plant performance under water deficits, efforts are being made to elucidate the nature of water-stress tolerance in an attempt to improve maize hybrids further. Such factors include better partitioning of biomass to the developing ear resulting in faster spikelet growth and improved reproductive success. An emphasis on faster spikelet growth rate may result in a reduction in the number of spikelets formed on the ear that facilitates overall seed set by reducing water and carbon constraints per spikelet. To understand the molecular mechanisms for drought tolerance in improved maize lines better, a variety of genomic tools are being used. Newer molecular markers and comprehensive gene expression profiling methods provide opportunities to direct the continued breeding of genotypes that provide stable grain yield under widely varied environmental conditions.
        Bookmark
        • Record: found
        • Abstract: not found
        • Article: not found

        Maize breeding in the tropics

          Bookmark
          • Record: found
          • Abstract: not found
          • Article: not found

          Recursos genéticos vegetais

            Bookmark

            Author and article information

            Affiliations
            [1 ] Embrapa Milho e Sorgo Brazil
            [2 ] Embrapa Meio-Norte Brazil
            Contributors
            Role: ND
            Role: ND
            Role: ND
            Role: ND
            Role: ND
            Role: ND
            Role: ND
            Role: ND
            Role: ND
            Role: ND
            Role: ND
            Journal
            cbab
            Crop Breeding and Applied Biotechnology
            Crop Breed. Appl. Biotechnol.
            Crop Breeding and Applied Biotechnology (Viçosa )
            1984-7033
            December 2010
            : 10
            : 4
            : 312-320
            S1984-70332010000400005
            10.1590/S1984-70332010000400005

            http://creativecommons.org/licenses/by/4.0/

            Product
            Product Information: SciELO Brazil
            Categories
            AGRONOMY
            BIOTECHNOLOGY & APPLIED MICROBIOLOGY

            Comments

            Comment on this article