Heterosis: Theory and Estimation
نویسندگان
چکیده
Heterosis is the foundation of modern maize breeding programs. Despite its importance in maize production, we know surprisingly little about the genetic basis of heterosis. Shull (1952) coined the term heterosis and defined it as: "... the interpretation of increased vigor, size, fruitfulness, speed of development, resistance to disease and to insect pests, or to climatic rigors of any kind, manifested by crossbred organisms as compared with corresponding inbreds, as the specific results of unlikeness in the constitutions of the uniting parental gametes.” This definition is often interpreted as not implying a genetic basis for heterosis, because the definition basically describes the phenotype that results from crossing two different inbred lines.
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