CONTENTS Preface Introduction Background and present status of silkworm breeding Background Present status of silkworm breeding Aims and achievements of silkworm breeding Genetic bases for heritable improvement and use of statistics The source of variation: gene pool Genetics of the silkworm Quantitative characters: heritability Quantitative characters: heterosis Application of statistics in silkworm breeding Establishing a silkworm breeding programme: major principles and techniques Introduction Establishing and maintaining a germplasm bank Inbreeding and techniques for pureline isolation Cross breeding techniques for hybridization Useful statistics and early generation testing Mutation breeding with translocation strains Cross breeding techniques Overview Mating/crossing techniques for silkworm breeding Screening for good inbred combiners: combining ability Techniques for selection Other aspects of silkworm breeding Breeding for resistance/tolerance to disease and adverse physical conditions Local adaptability test and authorization of commercial hybrids and their abolition Management of parental inbred stocks of commercial hybrids Annexes Outline of basic facilities, equipment, tools and expendables required for establishing a slikworm breeding programme International silkworm stock centres Rules, methods and techniques in silkworm breeding standard major test and examination items (UNIT)

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