83 Reproduction Modes of Crops and The Exploitation of Heterosis杂种优势的遗传基础 The basic principles of exploitation Easy Manipulation Low Cost (of seed production) Obvious heterosis 2. Reproduction modes and the exploitation Self pollinated and often cross pollinated plants Intervarietal hybrid; Male Sterility(cms, nms) Cross pollinated plants (Manual emasculation) Vegetatively propagated plants( Fixing heterosis)
§3 Reproduction Modes of Crops and The Exploitation of Heterosis 杂种优势的遗传基础 1. The Basic Principles of Exploitation ▪ Easy Manipulation ▪ Low Cost (of seed production) ▪ Obvious Heterosis 2. Reproduction modes and the Exploitation ▪ Self pollinated and often cross pollinated plants Intervarietal hybrid; Male Sterility (cms, nms) ▪ Cross pollinated plants (Manual emasculation) ▪ Vegetatively propagated plants (Fixing heterosis)
84 General Procedure for Hybrid Breeding 杂种优势的遗传基础 Types of Hybrids(or Hybrid varieties) Inter varietal Hybrid品种间杂种( Chemical way: wheat) Inter inbred line Hybrid自交系间杂交种( Maize) Inter self-incompatable line hybrid自交不亲和系杂交种 Inter specific Hybrid种间杂种Coon) Inter cytoplasmic vs nucleate hybrid核质杂种 Male sterility Hybrid雄性不育杂种(Rice) Three-line Hybrid Two-line Hybrid One-line Hybrid
§4 General Procedure for Hybrid Breeding 杂种优势的遗传基础 1. Types of Hybrids (or Hybrid Varieties) ▪ Inter varietal Hybrid 品种间杂种(Chemical way: wheat) ▪ Inter inbred line Hybrid 自交系间杂交种(Maize) ▪ Inter self-incompatable line Hybrid 自交不亲和系杂交种 ▪ Inter specific Hybrid 种间杂种(Cotton) ▪ Inter cytoplasmic vs nucleate Hybrid 核质杂种 ▪ Male sterility Hybrid 雄性不育杂种 (Rice) Three-line Hybrid Two-line Hybrid One-line Hybrid
2. Breeding of parent lines Breeding for inbred line in maize: Continuous self- breeding INbred Line is the offspring derived from a superior single plant after a series of artificial inbreeding(or self- breeding) and selection. An inbred line is a homozygous line. a pure line. a uniform line and a stable line. It can be reproduced faithfully year after year. It is essential for continuous production of hybrid seed of the same genetic constitution over years. It also ensures extreme uniformity in the hybrids
2. Breeding of Parent Lines ▪ Breeding for inbred line in maize: Continuous selfbreeding Inbred Line is the offspring derived from a superior single plant after a series of artificial inbreeding (or selfbreeding) and selection. An inbred line is a homozygous line, a pure line, a uniform line and a stable line. It can be reproduced faithfully year after year. It is essential for continuous production of hybrid seed of the same genetic constitution over years. It also ensures extreme uniformity in the hybrids