Perspectives on applied aspects of breeding for rust resistance
Singh, R.P.
Perspectives on applied aspects of breeding for rust resistance - 2013 - p. 10
Abstract only
Wheat breeding is largely conducted by the public institutions in Asia, Africa and Latin America; however, private sector engagement in South America and South Africa is substantial and is increasing in some other countries. A dynamic breeding program must target crossing by considering the situation that will prevail in 8-10 years when the derived varieties will be grown. A successful variety is the sum of various traits and resistance to a particular rust is just one but a crucial trait for focus. Therefore, a strategy that prolongs the effectiveness of resistance is of extreme importance in enhancing productivity gains while protecting the environment and farmers? incomes. There are numerous breeding programs worldwide and most operate with constraints. The capacity of a program to breed for rust resistance is enhanced when breeders, geneticists, pathologists and molecular biologists set goals together, and collaborate and work in harmony. Choice of resistance, race-specific or partial, and their utilization will depend on the commitment of individual breeding programs. It is often easier to use single race-specific resistance genes with large effects in breeding programs with limited resources; however, larger and more resourceful programs must commit to utilizing resistance genes more responsibly, i.e. using them in combinations or switching to more complex adult plant resistance (APR) based on multiple slow rusting, minor genes. Limited availability of effective race-specific genes, and tightly-linked molecular markers, usually leads to the utilization of the same genes by many breeding programs in time and space. This often leads to higher genetic vulnerability and losses across large areas when virulent races develop and spread. Maintaining diversity is therefore the key to overcoming ?boom-and bust? episodes if dependence on race-specific resistance is to prevail. The CIMMYT bread wheat breeding program has been successful in developing highyielding wheats that possess near-immune to adequate levels of APR to all three rusts. Large scale deployment of varieties with APR and removal of susceptible varieties from cultivationshould lead to sustainable long-term control of rusts.
English
Perspectives on applied aspects of breeding for rust resistance - 2013 - p. 10
Abstract only
Wheat breeding is largely conducted by the public institutions in Asia, Africa and Latin America; however, private sector engagement in South America and South Africa is substantial and is increasing in some other countries. A dynamic breeding program must target crossing by considering the situation that will prevail in 8-10 years when the derived varieties will be grown. A successful variety is the sum of various traits and resistance to a particular rust is just one but a crucial trait for focus. Therefore, a strategy that prolongs the effectiveness of resistance is of extreme importance in enhancing productivity gains while protecting the environment and farmers? incomes. There are numerous breeding programs worldwide and most operate with constraints. The capacity of a program to breed for rust resistance is enhanced when breeders, geneticists, pathologists and molecular biologists set goals together, and collaborate and work in harmony. Choice of resistance, race-specific or partial, and their utilization will depend on the commitment of individual breeding programs. It is often easier to use single race-specific resistance genes with large effects in breeding programs with limited resources; however, larger and more resourceful programs must commit to utilizing resistance genes more responsibly, i.e. using them in combinations or switching to more complex adult plant resistance (APR) based on multiple slow rusting, minor genes. Limited availability of effective race-specific genes, and tightly-linked molecular markers, usually leads to the utilization of the same genes by many breeding programs in time and space. This often leads to higher genetic vulnerability and losses across large areas when virulent races develop and spread. Maintaining diversity is therefore the key to overcoming ?boom-and bust? episodes if dependence on race-specific resistance is to prevail. The CIMMYT bread wheat breeding program has been successful in developing highyielding wheats that possess near-immune to adequate levels of APR to all three rusts. Large scale deployment of varieties with APR and removal of susceptible varieties from cultivationshould lead to sustainable long-term control of rusts.
English