International Journal of Molecular Ecology and Conservation, 2025, Vol.15, No.1, 30-43 http://ecoevopublisher.com/index.php/ijmec 36 (Wu et al., 2021). The team of Guangxi Academy of Agricultural Sciences in China reported obtaining mutant strains with stronger growth and shorter internodes through carbon ion mutagenesis screening. Methods such as radiation mutagenesis are expected to break the bottleneck of pitaya genetics and provide more materials for the breeding of new varieties. Molecular breeding and gene editing are currently in their infancy. With the establishment of pitaya genome sequencing and transformation system, it is possible to use MAS (marker-assisted selection) and genome editing technology for targeted improvement. In recent years, the draft of pitaya whole genome sequencing has been published, laying the foundation for the discovery of key genes related to disease resistance, stress resistance, and fruit quality (Li et al., 2025). For example, the structural genes and regulatory genes that control anthocyanin synthesis in pitaya have been found, which can be used to guide the breeding of new varieties with brighter flesh color and stronger antioxidants (Lin et al., 2021). In terms of disease resistance, Taiwanese scholars cloned disease-resistant transcription factor genes such as pitaya WRKY33, and after being transferred into pitaya, they significantly improved its resistance to stem blight (Luo et al., 2025). These research advances mean that in the future, pitaya varieties that are more tolerant to specific adversities can be cultivated through genetic engineering. Although there is no commercial application of genetically modified pitaya at present, molecular breeding is undoubtedly a powerful tool to improve breeding efficiency. 6.3 Integration of local and exotic germplasm in breeding Regional trials and selection of varieties are also important links in adaptive breeding. For different ecological zones, the agricultural department has established pitaya variety comparison test gardens to evaluate the regional adaptability of introduced and cultivated varieties. For example, the experiment in Rongjiang, Guizhou showed that the growth results of multiple introduced varieties in the local area were close to the level of the best production areas in Guizhou Province, proving that the climate in Rongjiang is suitable for promoting pitaya cultivation (Huang et al., 2024). For another example, Guangxi set up points in southern, central and northern Guangxi to test the yield and cold resistance of different varieties. The results showed that some varieties can be moved north to areas with an annual minimum temperature of around 0℃ for planting, and they can safely overwinter by covering and protecting them in winter. Through regional trials and screening, various regions have selected the main varieties suitable for their own environments. For example, Hainan mainly uses the early-maturing, high-sugar red meat "Dahong", while the western Guangdong region promotes high-yield and stable soft-branch white meat varieties. These practices reflect the principle of "selecting good varieties according to local conditions" and accelerate the renewal of varieties in yellow pitaya production. In the process of adaptive breeding, breeders also attach importance to maintaining genetic diversity to prevent the risk of single varieties. Some units have established core germplasm banks to classify and preserve germplasms with different genetic backgrounds, and carry out reincarnation selection to improve specific traits while retaining the diversity of the population as much as possible (Morillo et al., 2022). In addition, it is also very important to strengthen germplasm exchanges and joint breeding between different institutions. Research institutes in Guangxi, Guangdong and Vietnam have exchanged hybrid offspring materials many times, promoting the sharing of excellent genes. Internationally, some scholars have suggested establishing an international dragon fruit research alliance and germplasm sharing platform to integrate the breeding forces of various countries and avoid duplication of work. These measures are expected to accelerate the breeding of new yellow pitaya varieties that are more adaptable to a wide range of environments. 7 Case study: Regional Adaptability (e.g. Southeast Asia) 7.1 Germplasm introduction history and initial challenges Southeast Asia is one of the most successful regions for the introduction of yellow pitaya, with Vietnam and Thailand being particularly typical. Taking Vietnam as an example, dragon fruit has expanded rapidly in the country since the late 20th century, and its current planting area and output are among the highest in the world (Trindade et al., 2023). The climate in Binh Thuan Province and Tien Giang Province in the central and southern coastal areas of Vietnam is hot and rainy, which is very suitable for the growth of dragon fruit. Through trellis
RkJQdWJsaXNoZXIy MjQ4ODYzNA==