Triticeae Genomics and Genetics, 2024, Vol.15, No.2, 100-110 http://cropscipublisher.com/index.php/tgg 101 research direction. By synthesizing recent research findings, this study aims to provide a comprehensive understanding of the role of hybridization in advancing wheat genetic improvement and highlight its potential in addressing global food security challenges. 2 Historical Perspectives on Wide Hybridization 2.1 Early studies and milestones The concept of wide hybridization, which involves crossing different species or genera to introduce new genetic variations, has been a cornerstone in plant breeding for many decades. Early studies focused on the potential of wide hybridization to enhance crop traits such as yield, disease resistance, and stress tolerance. One of the pioneering efforts in this field was the exploration of hybridization between wheat and its wild relatives, which aimed to introduce beneficial traits from wild species into cultivated wheat varieties (Alvarez and Guzmán, 2018). These initial experiments laid the groundwork for understanding the genetic and phenotypic outcomes of wide hybridization. 2.2 Evolution of techniques and approaches Over the years, the techniques and approaches for wide hybridization have evolved significantly. Early methods primarily relied on conventional crossing techniques, which often faced challenges such as prezygotic and postzygotic barriers. To overcome these barriers, several advanced techniques have been developed, including chromosome doubling, bridging species, protoplast fusion, and embryo rescue (Anushma et al., 2021). These methods have proven highly beneficial in recovering fertile progenies from wide crosses, thereby enhancing the success rate of wide hybridization efforts. In recent times, the integration of genomic tools has further revolutionized wide hybridization. Genomic prediction and genome-wide association studies have enabled breeders to identify and select for desirable traits more efficiently. For instance, a three-step strategy involving genomic prediction has been developed to establish high-yielding heterotic patterns in hybrid wheat breeding (Zhao et al., 2015). This approach has shown promise in boosting grain yield and stability by exploiting heterosis, thereby marking a significant advancement in the field. 2.3 Case studies of successful wide hybrids Several case studies highlight the success of wide hybridization in wheat genetic improvement. One notable example is the hybridization between wheat and various species of the Poaceae and Panicoideae families, which resulted in the formation of both haploid and diploid embryos. These hybrids have demonstrated the potential to introduce new genetic variations that can be harnessed for crop improvement. Another successful case is the use of wild relatives and old varieties to enhance wheat grain quality. Hybridization events with these sources have been shown to enlarge the genetic variability for traits such as grain hardness, gluten quality, and nutritional components like vitamins and micronutrients (Alvarez and Guzmán, 2018). This approach has not only improved the technological and nutritional quality of wheat but also expanded the range of traits available for breeding programs. The historical perspectives on wide hybridization underscore its significance in wheat genetic improvement. From early studies and milestones to the evolution of advanced techniques and successful case studies, wide hybridization continues to be a vital tool in the quest for enhanced wheat varieties. 3 Mechanisms of Wide Hybridization 3.1 Genetic and genomic compatibility Wide hybridization involves crossing wheat with its wild or distantly related species to introduce new genetic diversity and desirable traits. The genetic compatibility between wheat and its relatives is crucial for successful hybridization. For instance, the genetic control of compatibility in crosses between wheat and its wild or cultivated relatives has been extensively studied, revealing that the genetic background of both the recipient and donor varieties significantly influences crossability (Laugerotte et al., 2022). Additionally, the use of wild relatives and old varieties has been shown to enhance wheat quality by introducing novel genetic variations
RkJQdWJsaXNoZXIy MjQ4ODYzNQ==