The plant breeding industry has sometimes been criticised for not driving increased robustness in their selection of new varieties. They have responded by saying that growers did not want them and that they were basically unsaleable as long as improved disease resistance was accompanied by lower yield.
It is generally accepted that disease resistance carries a yield drag in wheat but not in barley and the hope is that the drag can also be minimised, or even removed, in wheat in time.
Looking a decade ahead
At the ITLUS conference last December Ed Flatman, who is head of wheat research Europe at Limagrain, addressed the subject of new technologies in cereal breeding and spoke about how they will affect crop production in the medium to long term.
He began by stating that plant breeders work on a 7-8 year time span so their objectives today depend on their belief as to the requirements of a decade ahead. And these objectives must take into account the requirements of growers and end users, as indicated in Table 1.
These requirements will mean different things to different players.
Malting end users have very different requirements to feed producers and, as varieties get more sophisticated, distillers have different requirements to brewers.
Individual breweries have different requirements also. For growers, yield is important but so is standing power, disease resistance, sprouting resistance and, increasingly, field hardiness is an issue, especially at harvest.
While breeders can arguably tackle most of these requirements, the greater challenge is to be able to deliver them across increasingly variable external factors.
So breeders must try to be conscious of how climate change may alter the growing season as they look at how new varieties will interact with environmental factors such as:
Seasonal variability/unpredictability,Frequency and severity of epidemics,Sub-optimal timing for inputs;changing technology requirement such as:
Precision agriculture,End user processes or new markets,Novel breeding technology;and imposed legislative changes on issues such as:
Food quality regulations,Agrochemical withdrawals,Nitrate sensitivity,New breeding techniques (GE or GM).All of these things are very real for growers and users and it remains a big challenge for breeders to be able to counteract these evolving requirements for the different wheat zones of the world.
Ed used a work called ‘envirotyping’ which is a way the breeders look at plant materials with regard to flowering date, ripening dates and potential and actual yield levels.
All of these characteristics help to target specific genetic material in to specific geographies to help the efficiency and delivery of breeding.
So they attempt to incorporate climate change consequences into their focus for specific markets.
Breeding – an evolving process
Traditional plant breeding involved making crosses between chosen parents and assessing them over time in a process that tended to take around 10 years to get a new variety to market. This required growing each cross and then selecting the ones that looked to have desirable characteristics. This process involved the basic observations shown in Table 2.
This process was slow, and required a lot of space and labour. It had one major benefit in that the system helped to maintain considerable diversity in the gene pool for breeders.
There have been many efficiencies brought into this process over the years.
If we call the traditional process pedigree breeding, single seed decent enables 2-3 seed generation to be produced per year and this takes one to two fewer years to market.
Double haploid breeding is even faster, requires tissue culture as part of the process and shortens the pedigree process by two to three years.
Gene technology has helped breeders have a better understanding of the importance of specific genes
However, the increased understanding of the function of individual genes has brought considerable further benefit. This enables them to look for specific desirable genes following a cross and the cost of using this process has become considerably cheaper in recent years following technology development.
Gene technology has helped breeders have a better understanding of the importance of specific genes and there is an increasing knowledge and catalogue of commercially important genes to be used.
A number of commercially important genes are now associated with disease resistance, agronomic traits, grain quality and yield
This information enables them to better target the genes they want to combine and they can use a range of other tools to check for the presence of these in a new cross.
A number of commercially important genes are now associated with disease resistance, agronomic traits, grain quality and yield (grain size).
And the technologies enable the profiling of parent varieties ahead of a cross, selecting specific crosses using genetics or marker assisted traits following crossing, intense early stage selection of new crosses and they help in the stacking of novel gene combinations for specific traits.
Biological processes
We will come to depend more on the resistance traits of varieties to help control biological processes like diseases and pests.
These new breeding tools enable increased focus on specific objectives and increase the accuracy of their delivery
But Ed stated that genetics can only be part of the solution and that genetic resistance will be important to add flexibility to standard husbandry.
These new breeding tools enable increased focus on specific objectives and increase the accuracy of their delivery.
But genetic resistance can be broken also and so systems will still require some combination of genetic and plant protection.
Knowing the genes and the use of marker assistance enables the production and use of stacked traits, even in conventional varieties
He said that genotyping is increasingly important, as this involves the identification of single genes with large effect (very subject to being overcome by nature) and multiple genes with small effect (eg yield).
When used to combat a disease, the latter may appear less strong initially, but it may also prove to be much more robust over time because of its multiple effects.
Knowing the genes and the use of marker assistance enables the production and use of stacked traits, even in conventional varieties.
Technologies like gene transfer and gene editing (CRISPR) have a lot to offer in terms of producing a specific set of characteristics, but they are not allowed in the EU.
However, they can still be useful in demonstrating possible useful traits.
Ed also spoke about the use of technology to help identify new methods of resistance. He told of how research had identified multiple sources/types of resistance in both commercial varieties and pre-commercial breeding lines.
High density DNA mapping then enabled a pipeline of DNA marker development which could be intensely screened in multiple high pressure septoria tritici locations.
Similar technologies can be used to better understand yield delivery or other traits such as sprouting resistance
Having this knowledge enabled the objective to stack multiple genes, increase the level of resistance and limit the risk of breakdown.
Similar technologies can be used to better understand yield delivery or other traits such as sprouting resistance.
F1 hybrids are also being examined again for wheat because they bring automatic gain and robustness through hybrid vigour (heterosis). However to be commercial this will require a cost effective seed production system to help make it a commercial reality.
Genomic selection is now part of modern plant breeding. The process enables the more focused delivery of commercially important traits. It requires the use of many new tools and technologies which help to deliver a package of desirable traits to growers in a shorter time frame. And there is little doubt but that the technology package will continue to deliver increased accuracy and speed.
The plant breeding industry has sometimes been criticised for not driving increased robustness in their selection of new varieties. They have responded by saying that growers did not want them and that they were basically unsaleable as long as improved disease resistance was accompanied by lower yield.
It is generally accepted that disease resistance carries a yield drag in wheat but not in barley and the hope is that the drag can also be minimised, or even removed, in wheat in time.
Looking a decade ahead
At the ITLUS conference last December Ed Flatman, who is head of wheat research Europe at Limagrain, addressed the subject of new technologies in cereal breeding and spoke about how they will affect crop production in the medium to long term.
He began by stating that plant breeders work on a 7-8 year time span so their objectives today depend on their belief as to the requirements of a decade ahead. And these objectives must take into account the requirements of growers and end users, as indicated in Table 1.
These requirements will mean different things to different players.
Malting end users have very different requirements to feed producers and, as varieties get more sophisticated, distillers have different requirements to brewers.
Individual breweries have different requirements also. For growers, yield is important but so is standing power, disease resistance, sprouting resistance and, increasingly, field hardiness is an issue, especially at harvest.
While breeders can arguably tackle most of these requirements, the greater challenge is to be able to deliver them across increasingly variable external factors.
So breeders must try to be conscious of how climate change may alter the growing season as they look at how new varieties will interact with environmental factors such as:
Seasonal variability/unpredictability,Frequency and severity of epidemics,Sub-optimal timing for inputs;changing technology requirement such as:
Precision agriculture,End user processes or new markets,Novel breeding technology;and imposed legislative changes on issues such as:
Food quality regulations,Agrochemical withdrawals,Nitrate sensitivity,New breeding techniques (GE or GM).All of these things are very real for growers and users and it remains a big challenge for breeders to be able to counteract these evolving requirements for the different wheat zones of the world.
Ed used a work called ‘envirotyping’ which is a way the breeders look at plant materials with regard to flowering date, ripening dates and potential and actual yield levels.
All of these characteristics help to target specific genetic material in to specific geographies to help the efficiency and delivery of breeding.
So they attempt to incorporate climate change consequences into their focus for specific markets.
Breeding – an evolving process
Traditional plant breeding involved making crosses between chosen parents and assessing them over time in a process that tended to take around 10 years to get a new variety to market. This required growing each cross and then selecting the ones that looked to have desirable characteristics. This process involved the basic observations shown in Table 2.
This process was slow, and required a lot of space and labour. It had one major benefit in that the system helped to maintain considerable diversity in the gene pool for breeders.
There have been many efficiencies brought into this process over the years.
If we call the traditional process pedigree breeding, single seed decent enables 2-3 seed generation to be produced per year and this takes one to two fewer years to market.
Double haploid breeding is even faster, requires tissue culture as part of the process and shortens the pedigree process by two to three years.
Gene technology has helped breeders have a better understanding of the importance of specific genes
However, the increased understanding of the function of individual genes has brought considerable further benefit. This enables them to look for specific desirable genes following a cross and the cost of using this process has become considerably cheaper in recent years following technology development.
Gene technology has helped breeders have a better understanding of the importance of specific genes and there is an increasing knowledge and catalogue of commercially important genes to be used.
A number of commercially important genes are now associated with disease resistance, agronomic traits, grain quality and yield
This information enables them to better target the genes they want to combine and they can use a range of other tools to check for the presence of these in a new cross.
A number of commercially important genes are now associated with disease resistance, agronomic traits, grain quality and yield (grain size).
And the technologies enable the profiling of parent varieties ahead of a cross, selecting specific crosses using genetics or marker assisted traits following crossing, intense early stage selection of new crosses and they help in the stacking of novel gene combinations for specific traits.
Biological processes
We will come to depend more on the resistance traits of varieties to help control biological processes like diseases and pests.
These new breeding tools enable increased focus on specific objectives and increase the accuracy of their delivery
But Ed stated that genetics can only be part of the solution and that genetic resistance will be important to add flexibility to standard husbandry.
These new breeding tools enable increased focus on specific objectives and increase the accuracy of their delivery.
But genetic resistance can be broken also and so systems will still require some combination of genetic and plant protection.
Knowing the genes and the use of marker assistance enables the production and use of stacked traits, even in conventional varieties
He said that genotyping is increasingly important, as this involves the identification of single genes with large effect (very subject to being overcome by nature) and multiple genes with small effect (eg yield).
When used to combat a disease, the latter may appear less strong initially, but it may also prove to be much more robust over time because of its multiple effects.
Knowing the genes and the use of marker assistance enables the production and use of stacked traits, even in conventional varieties.
Technologies like gene transfer and gene editing (CRISPR) have a lot to offer in terms of producing a specific set of characteristics, but they are not allowed in the EU.
However, they can still be useful in demonstrating possible useful traits.
Ed also spoke about the use of technology to help identify new methods of resistance. He told of how research had identified multiple sources/types of resistance in both commercial varieties and pre-commercial breeding lines.
High density DNA mapping then enabled a pipeline of DNA marker development which could be intensely screened in multiple high pressure septoria tritici locations.
Similar technologies can be used to better understand yield delivery or other traits such as sprouting resistance
Having this knowledge enabled the objective to stack multiple genes, increase the level of resistance and limit the risk of breakdown.
Similar technologies can be used to better understand yield delivery or other traits such as sprouting resistance.
F1 hybrids are also being examined again for wheat because they bring automatic gain and robustness through hybrid vigour (heterosis). However to be commercial this will require a cost effective seed production system to help make it a commercial reality.
Genomic selection is now part of modern plant breeding. The process enables the more focused delivery of commercially important traits. It requires the use of many new tools and technologies which help to deliver a package of desirable traits to growers in a shorter time frame. And there is little doubt but that the technology package will continue to deliver increased accuracy and speed.
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