Scholarlink

<p>In bread wheat breeding, connecting genetic diversity is considered important for exploiting positive Genotype-by-Environment Interactions (GEI) and developing stable, climate-resilient varieties. This study investigates the genetic diversity, GEI and stability of thirty bread wheat varieties, with the overall objective of this study was to decipher the relationship between allelic diversity and yield stability in bread wheat to identify optimal genotypes for breeding. Field trials were conducted using an alpha lattice design with two replications across six environments. AMMI and GGE biplot analyses revealed significant GEI, which accounted for 29.9% of the total variation in grain yield. Genetic diversity analysis of the 41 varieties revealed moderate variation, with an observed heterozygosity (Ho = 0.33) and an average polymorphic information content (PIC = 0.53), indicating a moderately diverse gene pool. Nucleotide diversity (π = 8.409688 × 10 − 6) suggests extremely low genetic variation within the population, raising concerns about the crop’s long-term adaptability to rapidly changing environmental conditions. High major allele frequencies (MaF = 0.8) and a low average minor allele frequency (MAF = 0.2). This indicates a skewed allelic distribution with very limited rare alleles, raising concerns about the population’s long-term adaptive capacity. This multi-environment evaluation study revealed distinct performance patterns among the wheat genotypes. The varieties (G4, G26, G1, G30, and G21) demonstrated both high yield potential and exceptional stability across diverse growing conditions. Particularly, genotypes G4 and G26, which uniquely combined superior agronomic performance with enrichment of rare alleles, positioning them as premier candidates for direct breeding applications and cultivar development. A central paradox emerged: genotypes with the highest overall allelic diversity G8, G13, G15) exhibited poor yield stability. This contrasts sharply with the stable, high-yielding genotypes, which possessed more targeted, functionally relevant allelic combinations. This stood in direct contrast to the stable genotypes that possessed more targeted, functionally relevant allelic content. This finding challenges the common assumption that broad genetic diversity alone ensures adaptive potential, instead suggesting that specific allelic combinations, rather than overall richness, may play a larger role in governing stability mechanisms.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

The paradox of diversity: high allelic richness does not ensure genotypic stability in bread wheat varieties (Triticum aestivum L.)

  • 期刊论文

  • 发表日期：

    2026年3月19日

查看全文
  • Sefawdin Berta Bedassa,
  • Zerihun Tadesse,
  • Techale Birhan,
  • Temesgen Matiwos Menamo,
  • Abush Tesfaye Abebe

摘要

In bread wheat breeding, connecting genetic diversity is considered important for exploiting positive Genotype-by-Environment Interactions (GEI) and developing stable, climate-resilient varieties. This study investigates the genetic diversity, GEI and stability of thirty bread wheat varieties, with the overall objective of this study was to decipher the relationship between allelic diversity and yield stability in bread wheat to identify optimal genotypes for breeding. Field trials were conducted using an alpha lattice design with two replications across six environments. AMMI and GGE biplot analyses revealed significant GEI, which accounted for 29.9% of the total variation in grain yield. Genetic diversity analysis of the 41 varieties revealed moderate variation, with an observed heterozygosity (Ho = 0.33) and an average polymorphic information content (PIC = 0.53), indicating a moderately diverse gene pool. Nucleotide diversity (π = 8.409688 × 10 − 6) suggests extremely low genetic variation within the population, raising concerns about the crop’s long-term adaptability to rapidly changing environmental conditions. High major allele frequencies (MaF = 0.8) and a low average minor allele frequency (MAF = 0.2). This indicates a skewed allelic distribution with very limited rare alleles, raising concerns about the population’s long-term adaptive capacity. This multi-environment evaluation study revealed distinct performance patterns among the wheat genotypes. The varieties (G4, G26, G1, G30, and G21) demonstrated both high yield potential and exceptional stability across diverse growing conditions. Particularly, genotypes G4 and G26, which uniquely combined superior agronomic performance with enrichment of rare alleles, positioning them as premier candidates for direct breeding applications and cultivar development. A central paradox emerged: genotypes with the highest overall allelic diversity G8, G13, G15) exhibited poor yield stability. This contrasts sharply with the stable, high-yielding genotypes, which possessed more targeted, functionally relevant allelic combinations. This stood in direct contrast to the stable genotypes that possessed more targeted, functionally relevant allelic content. This finding challenges the common assumption that broad genetic diversity alone ensures adaptive potential, instead suggesting that specific allelic combinations, rather than overall richness, may play a larger role in governing stability mechanisms.