In the pedigree selection method, a detailed record of the relationship between selected plants and their progenies is meticulously maintained via a pedigree record. This record functions as a genetic family tree. Each selected plant and its subsequent progeny rows are assigned unique identifiers. Detailed notes accompany these, documenting parentage, specific selection criteria, observed traits (e.g., yield, disease resistance, maturity), and environmental conditions in each generation. This comprehensive documentation allows breeders to trace any desirable plant's ancestry back to its original single-plant selection, providing crucial genetic lineage information.

Procedure for Pedigree Selection Method (Simplified Schematic Description):

The process involves systematic selection across generations, with records linking each plant to its ancestry:

• Year 1 (F2 Generation):

  • Start: A large F2 population (from a cross) is grown, exhibiting maximum genetic variation.

  • Selection: Individual, superior plants are carefully selected based on desired traits and harvested separately.

  • Record: Each selected F2 plant receives a unique pedigree number (e.g., F2-1).

• Year 2 (F3 Generation):

  • Progeny Rows: Seeds from each selected F2 plant are sown in separate progeny rows (e.g., F3-1 from F2-1).

  • Selection: Individual desirable plants are again selected within the best F3 progeny rows, focusing on uniformity.

  • Record: Selected F3 plants are numbered to reflect parentage (e.g., F3-1-1 from F3-1).

• Years 3-5 (F4 to F6 Generations):

  • Continued Selection & Homozygosity: This pattern continues. Selection becomes increasingly stringent on superior and highly uniform progeny rows as homozygosity increases. By F5-F6, lines typically achieve high genetic stability.

  • Record: Pedigree records are maintained (e.g., F4-1-1-1 from F3-1-1).

• Years 6-7 (Yield Trials):

  • Evaluation: Stable, homozygous lines advance to preliminary yield trials (PYT) to assess performance against standard varieties. Top lines proceed to multi-location advanced yield trials (AYT) for wider evaluation.

The continuous, nested numbering system (e.g., F2-1 → F3-1-1 → F4-1-1-1) acts as the "schematic diagram," inherently visualizing the genetic "family tree." This meticulous pedigree record is indispensable for genetic traceability and efficient, targeted breeding, culminating in new variety release.