The use of genetic diversity from emmer wheat to improve bread wheat
Access status:
Open Access
Type
ThesisThesis type
Doctor of PhilosophyAuthor/s
Ma'arup, RohayuAbstract
Drought can be defined by Cambridge Dictionary as long period with little or no rain. Australia is the seventh largest wheat producer in the world, but it is the driest inhabited continent from the viewpoint of continental rainfall and streamflow. So, genetic improvement through ...
See moreDrought can be defined by Cambridge Dictionary as long period with little or no rain. Australia is the seventh largest wheat producer in the world, but it is the driest inhabited continent from the viewpoint of continental rainfall and streamflow. So, genetic improvement through crossing high-yielding cultivars of bread wheat with cultivated emmer wheats (had gone through early screening), subsequently backcrossing with bread wheat to increase bread wheat characteristics and producing doubled haploid (DH) from BC1F1 is one possible solution for increasing the yield stability of wheat in drought prone areas. The key point of this research study was to evaluate physiological and agronomic traits among the DH lines in optimum conditions for them to fully express their highest potential in 2013. Subsequently, selection was made among the DH lines for two years of trials under irrigated and rainfed conditions (to mimic drought) in 2014-2015 to evaluate genotypes that use water efficiently under drought stress. The relationship of physiology, phenology, and yield components in high water use efficiency genotypes revealed aspects of adaptation in northwestern NSW. The comparisons of bread wheat parents and their respective progenies (DH lines) were explored and diverse responses to soil water stress were observed. Biplot genotype main effect plus genotype by environment interaction (G+GE) of the multi-environment trials (METs) identified ideal genotypes that are stable cultivars across environment. These findings were also strengthened with GWAS analysis that revealed marker trait associations (MTAs) in water deficit conditions were not observed under the irrigated environments. Such lines would allow farmers to maintain income during drought years, as well as increase their income during wet years. The outcomes from this study should be worthwhile to the wheat industries in Australia and India, as some of domesticated bread wheat parents used were commercial cultivars in India.
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See moreDrought can be defined by Cambridge Dictionary as long period with little or no rain. Australia is the seventh largest wheat producer in the world, but it is the driest inhabited continent from the viewpoint of continental rainfall and streamflow. So, genetic improvement through crossing high-yielding cultivars of bread wheat with cultivated emmer wheats (had gone through early screening), subsequently backcrossing with bread wheat to increase bread wheat characteristics and producing doubled haploid (DH) from BC1F1 is one possible solution for increasing the yield stability of wheat in drought prone areas. The key point of this research study was to evaluate physiological and agronomic traits among the DH lines in optimum conditions for them to fully express their highest potential in 2013. Subsequently, selection was made among the DH lines for two years of trials under irrigated and rainfed conditions (to mimic drought) in 2014-2015 to evaluate genotypes that use water efficiently under drought stress. The relationship of physiology, phenology, and yield components in high water use efficiency genotypes revealed aspects of adaptation in northwestern NSW. The comparisons of bread wheat parents and their respective progenies (DH lines) were explored and diverse responses to soil water stress were observed. Biplot genotype main effect plus genotype by environment interaction (G+GE) of the multi-environment trials (METs) identified ideal genotypes that are stable cultivars across environment. These findings were also strengthened with GWAS analysis that revealed marker trait associations (MTAs) in water deficit conditions were not observed under the irrigated environments. Such lines would allow farmers to maintain income during drought years, as well as increase their income during wet years. The outcomes from this study should be worthwhile to the wheat industries in Australia and India, as some of domesticated bread wheat parents used were commercial cultivars in India.
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Date
2016-12-31Faculty/School
Faculty of Agriculture and EnvironmentAwarding institution
The University of SydneyShare