An overview of some priorities of CIMMYT's wheat improvement program
Braun, H.J.
An overview of some priorities of CIMMYT's wheat improvement program - Tbilisi (Georgia) CIMMYT : 2004. - p. 247-248 - Printed
Global wheat consumption has constantly grown over the last 30 years and reached an ever high of600 million tons in 2002/03. Basically all of this growth occurred in LDC. Contrary to the increasing demand, global wheat production decreased at constant rates from 610 million tons in 1997/98 to 548 million tons in 2003/04 resulting in the lowest wheat reserves since 1981. Major reasons for the decreasing production where low wheat prices, government policies in wheat exporting countries as well as low yields due to environmental reasons in some major wheat producing countries. However, all production forecasts stress the increasing demand for wheat, which mainly occurs in less developed countries. An increase of at least 1.5% annually will be required to meet the demand of our growing world population for the next 20 years. Due to land limitations, this increase must come primarily from higher unit grain yield. Declining soil fertility in many regions and an increasing competition for water further requires that more grain is produced with less water in often increasingly less fertile soils. To meet this demand is a striking challenge for wheat researchers and growers. Breeding efforts at CIMMYT put major emphasis on increasing water-use efficiency; both in lines targeted for dryland and irrigated areas. The strategy is based on a multi-disciplinary approach. An increasing flow of information enables breeders to make "smarter crosses" with clearly defined targets and new tools contribute to increase selection efficiency. New methods and approaches used at CIMMYT include: Canopy temperature depression allows selection for higher yield in drought environments, since cooler canopy is highly correlated with root length density. Exploitation of novel genetic resources identified tolerance and resistance to many biotic and abiotic stresses as well as increased yield under drought. At present, around 40% of all CIMMYT spring wheat lines targeted for dryland areas are derived from synthetics, (T1: Turgidum, Ae. tauschii. .Introgression of slow rusting genes for leaf and yellow rusts using the limited backcross strategy has resulted in the development of cultivars with durable resistance and yields higher than the recurrent parent. The release of such cultivars is crucial as some of the most widely grown wheat . varieties are susceptible to new rust races. To further increase the tolerance to drought stress, wheat has been transformed at CIMMYT using the DREB 1 gene from Arabidopsis thaliana. These trials are currently being conducted under field like conditions in Mexico in a screen house, applying strictest bio- safety procedures. Wheat is the world's most important food energy source and provides in some countries up to 60% of the daily calorie uptake. Since its micro- nutrient content is low, many governments require wheat flour to be fortified with Vitamin A, iron, zinc and recently folic acid. But fortified flour does often not reach the poorest. Provided zinc and iron concentration in the grain can be increased, this will have a major impact on the diet of those, who consume mainly wheat, as iron and zinc deficiency are among the most wide spread deficiencies in humans. Wheat lines are currently developed with an increased grain zinc concentration and will be field tested within the next years. For the next decades, major world wide gains from wheat breeding are still likely to come to a great extent from conventional breeding methods, better use of current and expanded genetic diversity and better utilization of available data. But the recent breakthrough in transforming wheat and the fast growing impact from MAS greatly enhances the breeder's arsenal of tools to develop the wheat cultivars farmers need to feed the still fast growing population.
Text in English
Centro Internacional de Mejoramiento de Maiz y Trigo (CIMMYT)
Agricultural policies
Economic analysis
Environmental factors
Food resources
Grain yield
Seed production
Wheat
Plant breeding
CIMMYT
An overview of some priorities of CIMMYT's wheat improvement program - Tbilisi (Georgia) CIMMYT : 2004. - p. 247-248 - Printed
Global wheat consumption has constantly grown over the last 30 years and reached an ever high of600 million tons in 2002/03. Basically all of this growth occurred in LDC. Contrary to the increasing demand, global wheat production decreased at constant rates from 610 million tons in 1997/98 to 548 million tons in 2003/04 resulting in the lowest wheat reserves since 1981. Major reasons for the decreasing production where low wheat prices, government policies in wheat exporting countries as well as low yields due to environmental reasons in some major wheat producing countries. However, all production forecasts stress the increasing demand for wheat, which mainly occurs in less developed countries. An increase of at least 1.5% annually will be required to meet the demand of our growing world population for the next 20 years. Due to land limitations, this increase must come primarily from higher unit grain yield. Declining soil fertility in many regions and an increasing competition for water further requires that more grain is produced with less water in often increasingly less fertile soils. To meet this demand is a striking challenge for wheat researchers and growers. Breeding efforts at CIMMYT put major emphasis on increasing water-use efficiency; both in lines targeted for dryland and irrigated areas. The strategy is based on a multi-disciplinary approach. An increasing flow of information enables breeders to make "smarter crosses" with clearly defined targets and new tools contribute to increase selection efficiency. New methods and approaches used at CIMMYT include: Canopy temperature depression allows selection for higher yield in drought environments, since cooler canopy is highly correlated with root length density. Exploitation of novel genetic resources identified tolerance and resistance to many biotic and abiotic stresses as well as increased yield under drought. At present, around 40% of all CIMMYT spring wheat lines targeted for dryland areas are derived from synthetics, (T1: Turgidum, Ae. tauschii. .Introgression of slow rusting genes for leaf and yellow rusts using the limited backcross strategy has resulted in the development of cultivars with durable resistance and yields higher than the recurrent parent. The release of such cultivars is crucial as some of the most widely grown wheat . varieties are susceptible to new rust races. To further increase the tolerance to drought stress, wheat has been transformed at CIMMYT using the DREB 1 gene from Arabidopsis thaliana. These trials are currently being conducted under field like conditions in Mexico in a screen house, applying strictest bio- safety procedures. Wheat is the world's most important food energy source and provides in some countries up to 60% of the daily calorie uptake. Since its micro- nutrient content is low, many governments require wheat flour to be fortified with Vitamin A, iron, zinc and recently folic acid. But fortified flour does often not reach the poorest. Provided zinc and iron concentration in the grain can be increased, this will have a major impact on the diet of those, who consume mainly wheat, as iron and zinc deficiency are among the most wide spread deficiencies in humans. Wheat lines are currently developed with an increased grain zinc concentration and will be field tested within the next years. For the next decades, major world wide gains from wheat breeding are still likely to come to a great extent from conventional breeding methods, better use of current and expanded genetic diversity and better utilization of available data. But the recent breakthrough in transforming wheat and the fast growing impact from MAS greatly enhances the breeder's arsenal of tools to develop the wheat cultivars farmers need to feed the still fast growing population.
Text in English
Centro Internacional de Mejoramiento de Maiz y Trigo (CIMMYT)
Agricultural policies
Economic analysis
Environmental factors
Food resources
Grain yield
Seed production
Wheat
Plant breeding
CIMMYT