A priori choice of hybrid parents in plants.
Plant breeding deals with high-yielding genotypes. However, how best to choose parents of these genotypes remains an unsolved question. Here, we focus on a priori choice based on parental distances by means of agronomic and molecular data. Despite numerous theoretical and empirical studies, a priori choice continues to be a controversial procedure. Both success and failure are commonly reported. We looked at these ambiguous results in order to investigate their possible causes. A total of 139 articles on genetic divergence were sampled to examine aspects such as type and number of markers utilized. We suggest that the mean number of 160, 281 and 25 for RAPD and RFLP markers, and SSR loci, respectively, which we found in these papers, should be increased for accurate analysis. A second sample composed of 54 articles was used to evaluate the divergence-heterosis association. Most of them (28) detected positive divergence-heterosis association, whereas 26 revealed negative or inconclusive results. We examined several causes that influence a priori choice positively and negatively.
Dias
Luiz Antônio dos Santos
LA
Departamento de Biologia Geral, BIOAGRO, Universidade Federal de Viçosa, Viçosa, MG, Brasil. lasdias@ufv.br
Picoli
Edgard Augusto de Toledo
EA
Rocha
Rodrigo Barros
RB
Alfenas
Acelino Couto
AC
D001947:Breeding / Q000379:methods*; D017343:Genes, Plant / Q000235:genetics*; D005819:Genetic Markers; D014644:Genetic Variation; D005838:Genotype; D006823:Hybrid Vigor / Q000235:genetics*; D015810:Linkage Disequilibrium / Q000235:genetics*; D018895:Microsatellite Repeats; D012150:Polymorphism, Restriction Fragment Length; D019655:Quantitative Trait, Heritable; D019105:Random Amplified Polymorphic DNA Technique; D015203:Reproducibility of Results
D005819:Genetic Markers