Genomics and Applied Biology 2024, Vol.15, No.6, 320-332 http://bioscipublisher.com/index.php/gab 321 (Abouseadaa et al., 2020). These technologies not only contribute to the taxonomy and characterization of cactus species but also facilitate the identification of target traits in breeding programs, ultimately cultivating species with enhanced stress resistance, nutritional value, and medicinal properties. This study systematically analyzes recent advancements in genetic improvement technologies for Cactaceae plants and evaluates their potential in addressing the current challenges faced by these plants. The study explores and understands traditional and modern breeding methods, seeking to identify key genetic markers and traits that can be utilized in breeding programs. Case studies are also integrated to determine future directions that may further advance the genetic improvement of Cactaceae. This study is expected to provide a comprehensive understanding of the genetic patterns of Cactaceae plants, offering strong theoretical support and practical guidance for their future improvement and conservation. 2 Genetic Diversity of Cactaceae 2.1 Current status of genetic diversity The Cactaceae family, comprising over 140 genera and 2 000 species, exhibits significant genetic variation. Studies have shown that species within this family, such as those in the genera Mammillaria and Notocactus, display considerable genetic diversity, which is evident through the use of gene-targeting marker techniques like Start Codon Targeted (SCoT) Polymorphism and Conserved DNA-Derived Polymorphism (CDDP) (Abouseadaa et al., 2020). Additionally, the pitaya (Hylocereus undatus) genome has revealed extensive genetic variation, including whole-genome triplication and duplication events, which contribute to its genetic diversity (Chen et al., 2021). Various molecular techniques are employed to assess genetic diversity in Cactaceae. Randomly Amplified Polymorphic DNA (RAPD) markers are commonly used to identify and characterize genetic variations (Ferreira et al., 2023). Other advanced methods include RAD-Seq single-nucleotide polymorphism (SNP) data, which have been utilized to investigate hybridization and genetic architecture in Melocactus species (Khan et al., 2019). These techniques provide detailed insights into the genetic relationships and diversity within and between species. 2.2 Factors influencing genetic diversity Environmental factors play a crucial role in shaping the genetic diversity of Cactaceae. For instance, polyploidy, a significant mechanism in cactus speciation, is influenced by geographical and bioclimatic variables such as temperature and precipitation. Studies have shown that chromosome numbers in Cactaceae are related to temperature variables, while DNA contents are mostly associated with precipitation (Peñas et al., 2023). These findings suggest that environmental conditions drive genetic adaptations in cacti. Human activities, including habitat destruction and agricultural practices, significantly impact the genetic diversity of Cactaceae. The introduction of new cultivars through breeding programs, often involving somaclonal variation, can lead to genetic changes in crops. While somaclonal variation can generate beneficial traits, it also poses risks of reducing genetic diversity if not managed properly (Ferreira et al., 2023). Additionally, hybridization facilitated by human activities can affect the genetic integrity of species, as seen in Melocactus, where hybridization occurs frequently but with low introgression (Khan et al., 2019). 2.3 Importance of genetic diversity conservation Genetic diversity is vital for the adaptation and resilience of Cactaceae species. It enables populations to withstand environmental changes and resist diseases and pests. For example, the genetic diversity generated through somaclonal variation has supported the development of new genotypes resistant to various stresses (Ferreira et al., 2023). Similarly, the genetic variation observed in pitaya contributes to its adaptability and potential for genetic improvement (Chen et al., 2021). Conservation strategies are essential to protect the genetic resources of Cactaceae. These strategies include in situ conservation, which involves protecting natural habitats, and ex situ conservation, such as seed banks and botanical gardens. Additionally, molecular techniques can aid in the identification and preservation of genetic
RkJQdWJsaXNoZXIy MjQ4ODYzMg==