Intra‐varietal Diversification in Oat Breeding¹

Characterization in isogenic lines of oat crown rust resistance genes from four sources

“…The different isollnes are then mixed to give a host population that is heterogeneous for rust reaction (Borlaug, 19591 1965;Browning and Prey, I969;Jensen, 1952).…”

The release of genetically modified crops into the environment

“…Multi-lines consist of a mixture of inbred isogenic lines that share an identical genetic background but differ only with respect to a gene(s) for a specific trait. This concept was originally proposed as an approach to promote the durability of a cultivar by providing greater stability of production, broader adaptation to the environment, and greater protection against pathogen populations (Jenson, 1952). In contrast, multiblends involve a simple mixture of one or more cultivars that differ in a diverse range of traits.…”

Cultivar mixtures of processing tomato in an organic agroecosystem

“…Cultivar mixtures are a type of within-field diversification (Jensen 1952;de Vallavieille-Pope 2004). At present, their use has focused on disease management and yield.…”

“…Yield stability of crop mixtures can exceed that of their individual components across a range of soil types (Cowger and Weisz 2008). Nonetheless, farmers may be unwilling to risk lower yields in mixtures than in monocultures (Jensen 1952). It is often difficult to demonstrate that higher productivity occurs for mixtures than for the best-yielding monoculture, partly because so many different mixtures must be tested (Cardinale et al 2006).…”