A Diallel Selective Mating System for Cereal Breeding1

Abstract

The author proposes a set of diallel selective mating procedures to serve as a supplement to conventional breeding systems for autogamous crops. The system uses multiple parent input into a central gene pool (population) which, through selective mating of individuals is advanced through successive generations. Mass and recurrent selection procedures are employed throughout on both the plant and seed portions of each plant generation. The system is designed to shift the attention of breeders from the present operating concept of employing germplasm sources discretely and sequentially in the formation of numerous populations. In contrast, the diallel and selective mating aspects of the new system force the simultaneous insertion of multiple genotypes into a few central populations.The diallel selective mating system involves a planning phase and an implementation phase. The latter has four stages: a basic parent series of crosses (1) which set up the F1. diallel series of crosses (2) which when composited form P2; spaced P2 and subsequent P3, etc. provide the populations within which selective mating (3) is practiced on mass and recurrent selection principles. The final stage (4) is standard line selection from the various F5 composite populations.Implementation of the concept of the broad working gene pool leads to a continuing state of open options and provides the opportunity and time for alternative solutions to difficult breeding problems. Specifically, the proposed arrangements provide for broad use of germplasm, simultaneous input of parents, creation of persistent gene pools, breaking of linkage blocks, freeing of genetic variability, and general fostering of genetic recombination.