1 Introduction

Genetic diversity in rice is crucial for the sustainability and improvement of rice cultivation. It provides the genetic pool necessary for breeding programs aimed at enhancing yield, disease resistance, and adaptability to changing environmental conditions. The genetic variation within rice species allows for the identification of beneficial traits that can be harnessed to develop superior rice varieties. Studies have shown that genetic diversity is essential for maintaining the resilience of rice crops against biotic and abiotic stresses, thereby ensuring food security for a growing global population (Myint et al., 2012; Thant et al., 2021).

Myanmar’s rice germplasm, composed of diverse landrace varieties, represents a valuable yet underutilized genetic resource. This germplasm offers immense potential for rice breeding and genetic research, providing critical opportunities to develop new varieties with improved resilience, yield, and quality (Tun et al., 2006; Yamanaka et al., 2011; Myint et al., 2012; Watanabe et al., 2016; Thant et al., 2021). These landraces are adapted to various ecological zones across the country, including upland, lowland, and delta regions. In addition to their genetic uniqueness, Myanmar's landrace rice varieties are integral to the cultural and socio-economic fabric of the country. Research has demonstrated that Myanmar's rice varieties possess unique genetic traits, such as specific aroma genes and resistance to rice blast disease, which are not commonly found in other rice-growing regions (Myint et al., 2012; Ma et al., 2020; Thant et al., 2021). As the world faces increasing threats from climate change, pests, and diseases, the genetic reservoir found in Myanmar's rice landraces offers invaluable resources for breeding resilient and high-yielding rice varieties. The genetic diversity within these landraces is not only a testament to the country’s agricultural heritage but also a valuable resource for future rice breeding programs (Myint et al., 2023).

Recent research has underscored the rich genetic diversity found in Myanmar’s rice varieties, a significant reservoir of rice genetic resources. Thant et al. (2021), using DArTseq technology, identified two distinct population groups among 117 rice genotypes from the Ayeyarwady delta. Watanabe et al. (2016) evaluated 175 rice accessions from across Myanmar, revealing high genetic diversity and classifying them into indica and japonica groups. Furuta et al. (2024) contributed to the development of genomic resources for Myanmar’s rice germplasm by creating a diversity panel of 250 accessions and assembling a de novo genome of the Inn Ma Yebaw variety. These resources are intended to advance genetic research and breeding programs. Furthermore, Yan et al. (2010) analyzed the USDA Rice World Collection and found that the germplasm accessions from Myanmar were among the most diverse globally. Collectively, these studies highlight the critical role of Myanmar’s rice landraces in maintaining genetic diversity and their potential to enhance rice breeding efforts.

This study aims to synthesize current knowledge and existing research on the genetic diversity of Myanmar’s core landrace rice varieties. This includes an examination of the methodologies used to assess genetic variation, such as DArTseq-based SNP and silicoDArT markers, microsatellite loci, and functional molecular markers. Additionally, the study highlights the significance of these genetic studies in identifying useful DNA polymorphisms and specific genes that confer desirable phenotypic traits. By consolidating these findings, the study seeks to provide a comprehensive understanding of the genetic landscape of Myanmar’s rice varieties and their potential applications in rice breeding and conservation efforts.

2 Genetic Diversity in Rice: An Overview

2.1 Definition and importance of genetic diversity

Genetic diversity refers to the total number of genetic characteristics in the genetic makeup of a species. It is crucial for the adaptability and survival of populations, as it allows species to adapt to changing environmental conditions, resist diseases, and maintain ecosystem stability. In rice, genetic diversity is essential for breeding programs aimed at improving yield, disease resistance, and stress tolerance. The adaptability of a population is closely linked to its genetic variation, which influences fitness-related traits growth rate, reproductive success, and resistance to environmental stressors (Booy et al., 2000; Zhu et al., 2000).

2.2 Methods for assessing genetic diversity

Several methods are employed to assess genetic diversity in rice, each providing different levels of resolution and insights into the genetic makeup of populations Molecular markers such as Single Nucleotide Polymorphisms (SNPs) and Simple Sequence Repeats (SSRs) are commonly used. SNP markers provide detailed insights into genetic variation and population structure, as demonstrated in studies using Diversity Array Technology (DArT) based SNP markers. Recent studies have demonstrated the effectiveness of SNP markers using Diversity Array Technology (DArT)-based platforms to analyze genetic diversity in rice, revealing fine-scale population differentiation and adaptation patterns (Adeboye et al., 2020; Kimwemwe et al., 2023). SSR markers are also widely used due to their high polymorphism and ability to reveal genetic relationships among different rice cultivars (Jin et al., 2010; Chung et al., 2023). They have been successfully used to characterize genetic diversity and determine parentage in breeding programs (Jin et al., 2010; Chung et al., 2023). Other molecular markers, such as Amplified Fragment Length Polymorphisms (AFLPs) and Random Amplified Polymorphic DNA (RAPD), have also been used to analyze genetic diversity, although their use has declined with the advent of high-throughput sequencing methods. Next-Generation Sequencing (NGS) technologies, including whole-genome sequencing and genotyping-by-sequencing, provide comprehensive data on genetic variation, allowing for the identification of millions of SNPs and structural variations (Wang et al., 2018; Zhang et al., 2021). Genome-wide association Studies (GWAS) can assess genetic diversity in rice by identifying genetic variants linked to key traits and uncovering population structure. Zhao et al. (2011) used GWAS to analyze SNPs in diverse rice germplasm, revealing rich allelic diversity and population stratification. This method also highlights haplotype diversity and linkage disequilibrium patterns, offering valuable insights for rice breeding and genetic improvement. Additionally, genomic analyses, such as those conducted in the 3k Rice Genomes Project, offer comprehensive data on genetic variation and structural variations within rice populations (Figure 1) (Wang et al., 2018; Zhang et al., 2021).

Figure 1 Gene diversity in Asian cultivated rice (Adopted from Zhang et al., 2021) Image caption: (A) Frequency distribution of Shannon’s equitability (EH) calculated from the gene-CDS-haplotype (gcHap) dataset of 45 963 rice genes in 3KRG and its five rice populations. Five gene types were classified based on the distribution of their EH values in 3KRG. (B) Distribution of gcHap number (gcHapN) and EH of all 45 963 rice genes. (C) The relationship between EH and gcHapN of all 45 963 rice genes. (D) EH distribution of genes on 12 rice chromosomes. (E) Distribution of gcHapN (left) and EH (right) of known core, candidate core, and distributed genes of N-RefSeq from the RPAN database. PAV, gene presence/absence variation. (F) EH distribution of 20 gene clusters in 3KRG and its five rice populations (Adopted from Zhang et al., 2021)

2.3 Global perspectives on rice genetic diversity

Globally, rice genetic diversity has been extensively studied to understand its implications for breeding and conservation. For instance, the 3k Rice Genomes Project has provided valuable insights into the genetic structure and diversity of Asian cultivated rice, revealing subpopulations correlated with geographic locations and multiple domestication events (Wang et al., 2018). These findings provide critical insights for identifying genes associated with desirable agronomic traits, such as drought tolerance, disease resistance, and grain quality, which are vital for developing resilient rice varieties. Studies on upland rice germplasm have highlighted the significant genetic exchange and diversity within populations, which are crucial for rice improvement strategies (Adeboye et al., 2020). Furthermore, research on the genetic diversity of rice in different regions, such as the Democratic Republic of Congo and Egypt, underscores the importance of understanding local genetic resources for effective breeding programs (Jin et al., 2010; Kimwemwe et al., 2023). In India, extensive surveys of indigenous rice varieties have uncovered unique genetic traits for resistance to pests and extreme weather conditions, providing new opportunities for crop improvement in the face of climate change (Singh et al., 2019). The integration of genetic diversity into disease control strategies has also proven effective, as seen in the successful reduction of rice blast disease through genetic diversification in Yunnan Province, China (Salem et al., 2016). Advances in genomic technologies, such as genome-wide association studies (GWAS) and next-generation sequencing (NGS), have further facilitated the exploration of genetic diversity, enabling the identification of alleles associated with key traits and accelerating marker-assisted selection in breeding programs (Zhang et al., 2021).

Moreover, global initiatives such as the International Treaty on Plant Genetic Resources for Food and Agriculture and the efforts of institutions like the International Rice Research Institute (IRRI) aim to conserve and utilize rice genetic resources more effectively. The integration of traditional knowledge with advanced genomic tools and international collaboration is crucial for safeguarding and leveraging the genetic diversity of rice to address future challenges, including climate change, food security, and sustainability. By leveraging these diverse methods and global perspectives, researchers can better understand and utilize the genetic diversity of rice to enhance breeding programs develop climate-resilient cultivars, and ensure the long-term sustainability of rice production worldwide.

3 Historical Context of Myanmar’s Core Landrace Rice Varieties

Myanmar, historically known as Burma, has long been recognized as a primary center of plant genetic resources for rice. The country’s diverse ecosystems, ranging from hilly and mountainous regions to plateaus and plains, have contributed to the rich genetic diversity of rice varieties cultivated in the region. The interaction between Myanmar’s diverse ecosystems and its complex socio-economic factors, including trade, migration, and cultural exchanges, has further shaped the genetic landscape of its rice varieties. Moreover, rice cultivation in Myanmar is deeply intertwined with the country’s cultural heritage and societal structure, influencing not only agricultural practices but also culinary traditions and local festivals (Wang et al., 2019). The preservation of this genetic diversity is crucial for maintaining the resilience of rice crops against pests, diseases, and climate change, highlighting the importance of continuing efforts to conserve and study these valuable resources for future generations. The genetic diversity of Myanmar’s rice varieties has been shaped by centuries of traditional cultivation practices, socio-economic factors, and cultural significance.

3.1 Traditional cultivation practices in Myanmar

Traditional rice cultivation practices in Myanmar have played a crucial role in maintaining and enhancing the genetic diversity of rice varieties. These practices are generally grouped into lowland irrigated rice cultivation, rainfed lowland rice cultivation, upland (swidden or shifting) rice cultivation, deep water (floating) rice cultivation, and dry-season rice cultivation. Farmers in different regions have developed and preserved unique landrace varieties adapted to local environmental conditions. These practices include the selection of seeds from the best-performing plants, which has led to the development of rice varieties with desirable traits like aroma, grain quality, and resistance to pests and diseases. The use of diverse cultivation methods, such as upland and lowland farming, has further contributed to the genetic differentiation among rice varieties in Myanmar. Traditional practices such as crop rotation, intercropping, and organic fertilization not only enhance soil health but also promote the maintenance of genetic diversity by creating varied growing conditions. These methods have allowed farmers to cultivate rice varieties that are resilient to local environmental challenges and market demands, thereby preserving the rich genetic heritage of Myanmar’s rice crops (Myint et al., 2012; Na et al., 2016; Thant et al., 2021).

3.2 Evolution of landrace varieties in Myanmar

The evolution of landrace varieties in Myanmar has been influenced by both natural and human factors. Genetic studies have revealed that Myanmar’s rice varieties exhibit significant genetic diversity, with distinct population groups identified through various DNA markers. For instance, the use of DArTseq technology has shown a clear separation between traditional Pawsan varieties and modern high-yielding varieties, indicating a significant divergence in genetic makeup (Thant et al., 2021). Additionally, the presence of unique genetic clusters, such as the newly identified group 5B, highlights the distinct evolutionary pathways of Myanmar’s rice varieties compared to those from other regions (Myint et al., 2012). These findings reflect the impact of both geographic isolation and selective breeding practices by farmers who have cultivated rice under diverse agro-ecological zones ranging from upland to lowland areas.

The considerable genetic variation observed among Myanmar’s rice germplasm also points to the adaptive strategies developed by local communities in response to environmental stressors such as drought, flooding, and pests. This diversity is a valuable genetic resource for global rice breeding and improvement programs, offering traits that could enhance resilience to climate change and improve yield potential under challenging conditions (Tanksley & McCouch, 1997). The genetic variation observed in Myanmar’s rice germplasm underscores the importance of conserving these landrace varieties for future breeding and genetic improvement efforts (Na et al., 2016). Safeguarding this genetic diversity through both in situ and ex situ conservation strategies is crucial to ensuring food security and maintaining the ecological balance of rice ecosystems in Myanmar and beyond (Jarvis et al., 2008).

3.3 Socio-economic and cultural significance

Myanmar’s landrace rice varieties hold deep socio-economic and cultural significance, reflecting centuries of agricultural tradition and adaptation to the country’s diverse ecosystems. It is not only a staple food but also a key component of the country’s agricultural economy. The cultivation of traditional landrace varieties is deeply embedded in the cultural practices and traditions of Myanmar’s farming communities. These varieties are often associated with specific festivals, rituals, and culinary traditions, reflecting their cultural importance (Okoshi et al., 2018). The introduction of modern rice varieties has had mixed impacts on the genetic diversity of traditional landraces. While some modern varieties have displaced traditional ones, others have been integrated into local farming systems, maintaining a balance between modern and traditional practices (Steele et al., 2009). Conserving Myanmar’s landrace rice varieties is vital not only for maintaining the country’s cultural and agricultural heritage but also for securing future breeding programs. The rich genetic diversity within these varieties supports the development of resilient and high-yielding rice crops. (Na et al., 2016; Thant et al., 2021).

4 Molecular Techniques Used in Genetic Diversity Studies

4.1 DNA markers and their applications

DNA markers, such as SSR and DArTseq, play a crucial role in genetic diversity studies by revealing the genetic makeup and variability among rice varieties. These markers provide detailed insights, enabling the identification of genetic differences crucial for breeding and conservation efforts. In Myanmar, various DNA markers have been employed to assess the genetic diversity of rice landraces. A study used DArTseq-based SNP and silicoDArT markers to investigate the genetic diversity and population structure of local rice varieties in the Ayeyarwady delta. This study identified significant genetic variance among the genotypes and revealed two distinct population groups, highlighting the utility of these markers in distinguishing traditional and modern rice varieties (Thant et al., 2021). Similarly, SSR markers have been widely used to evaluate genetic diversity in rice. Studies have shown that SSR markers can produce polymorphic bands, revealing the population’s variability and aiding in the identification of genotypic differences and genetic relationships (Ram et al., 2010; Bhattacharjee et al., 2021; Hoque et al., 2022). Additionally, the use of SSR and ISSR markers in genomic studies has provided valuable information on the genetic diversity and population structure of rice genotypes, facilitating the selection of diverse and genetically distinct varieties for breeding (Kumbhar et al., 2015).

4.2 Genomic sequencing technologies

Genomic sequencing technologies have revolutionized the study of genetic diversity by providing high-resolution data on genetic variations. In Myanmar, DArTseq technology has been employed to explore the genetic diversity of rice varieties. This technology allows for the identification of thousands of SNP and silicoDArT markers, providing a comprehensive view of the genetic landscape of rice populations. The use of DArTseq technology in Myanmar’s rice genetic diversity studies has enabled researchers to identify useful DNA polymorphisms and specific genes conferring desirable phenotypic traits, which are crucial for genome-wide association studies and breeding programs (Thant et al., 2021).

4.3 Bioinformatics tools and data analysis methods

Bioinformatics tools and data analysis methods are integral to the interpretation of genetic diversity data. In Myanmar, a range of bioinformatics approaches have been applied to analyze data from DNA markers and genomic sequencing technologies. Techniques such as cluster analysis and analysis of molecular variance (AMOVA) have been used to assess genetic variation and population structure, revealing significant genetic divergence between populations and identifying distinct genetic clusters (Na et al., 2016; Thant et al., 2021). Additionally, methods like the unweighted pair group method with arithmetic mean (UPGMA) and principal coordinate analysis (PCA) are frequently employed to construct dendrograms and visualize genetic distances among rice genotypes. These approaches provide valuable insights into the genetic diversity and evolutionary relationships of Myanmar’s rice landraces (Yadav et al., 2019; Sao et al., 2020).

5 Key Findings from Genetic Diversity Studies in Myanmar

5.1 Genetic variation within and between landrace varieties

Genetic diversity within and between Myanmar’s rice landrace varieties has been extensively studied using various DNA markers. For instance, a study using DArTseq technology revealed significant genetic variance among 117 rice genotypes, with SNPs ranging from 0 to 0.753 and silicoDArT markers from 0.001 to 0.954. This study identified two distinct population groups and highlighted a significant divergence between traditional Pawsan varieties and modern high-yielding varieties, with 74% genetic variation at the population level (Thant et al., 2021).

A genetic analysis of Myanmar’s rice landraces using SSR markers was conducted and found considerable genetic variation both within and between populations. The study identified several unique alleles that are not found in other regional varieties, suggesting that Myanmar’s rice germplasm contains novel genetic materials that could be valuable for future breeding efforts (Yamanaka et al., 2011). Additional research by Watanabe (2016) explored the genetic diversity of Myanmar’s rice landraces using morphological and molecular markers, including SSR markers, to assess the genetic relationships among 150 rice accessions. This study found that Myanmar’s landrace varieties clustered into distinct genetic groups, indicating substantial genetic diversity and differentiation between upland and lowland ecotypes. Another study evaluated 175 rice accessions from different ecosystems in Myanmar, confirming high genetic diversity and classifying the accessions into two main cluster groups corresponding to indica and japonica groups (Na et al., 2016). These findings underscore the rich genetic diversity present within Myanmar’s rice landraces, which is crucial for future breeding programs.

5.2 Identification of unique genetic traits

Unique genetic traits have been identified in Myanmar’s rice varieties, particularly in aromatic rice. A study focusing on aromatic rice varieties discovered new BADH2 variants associated with aroma, including a 43 bp deletion in the 3’ UTR and a particular BADH2 allele with a 3 bp insertion, which was 100% associated with aroma (Myint et al., 2012). Additionally, the evaluation of physicochemical characteristics and genetic diversity of widely consumed rice varieties in the Kyaukse area identified superior cooking and eating quality traits in the famous Myanmar rice variety, Paw San Bay Kyar (PSBK), which exhibited intermediate amylose content, intermediate gelatinization temperature, soft gel consistency, and the highest elongation ratio among the studied varieties (Myint et al., 2023). These unique genetic traits are valuable for enhancing the quality and marketability of Myanmar’s rice.

5.3 Comparative studies with improved varieties

Comparative studies between landraces and improved rice varieties have highlighted the genetic distinctions and potential advantages of landraces. For example, a study using whole genome resequencing of 20 rice accessions, including javanica and indica, revealed significant genomic variations and identified candidate genes related to grain shape, such as TGW2, which performed better in landraces (Long et al., 2022) (Figure 2). Another study assessed the genetic diversity of traditional landraces and improved cultivars, finding higher genetic variations and observed heterozygosity in landraces compared to modern cultivars. This study also identified key genes involved in domestication and improvement, such as Kala4 and Ghd7, which are crucial for future breeding efforts (Zahra et al., 2020). One notable study comparing the genetic diversity of Myanmar’s landrace rice with improved varieties highlights the unique genetic variations present in landrace varieties. Conducted by Yamanaka et al. (2011), the study found that Myanmar’s landrace rice possesses distinct genetic variations that contribute significantly to stress tolerance and disease resistance, traits that are invaluable for breeding programs aimed at developing resilient rice varieties. These comparative studies demonstrate the genetic richness of landraces and their potential for contributing to rice improvement programs.

Figure 2 Phenotyping of the representative Oryza javanica and the source information (Adopted from Long et al., 2022) Image caption: The provided image consists of four panels (A, B, C, and D), each displaying different phenotypic and geographic information about Oryza javanica and Oryza indica rice varieties (Adopted from Long et al., 2022)

6 Implications for Rice Breeding and Conservation

6.1 Utilizing genetic diversity in breeding programs

The genetic diversity present in Myanmar’s core landrace rice varieties offers a valuable resource for breeding programs aimed at improving rice cultivars. Studies have shown that traditional landraces possess higher genetic variation compared to modern cultivars, which have a narrower genetic base due to selective breeding practices (Na et al., 2016; Zahra et al., 2020). This diversity can be harnessed to introduce desirable traits such as stress tolerance, disease resistance, and improved yield into new rice varieties. For instance, the identification of specific genes responsible for phenotypic traits through GWAS can guide the selection of parent plants for recombination breeding (Thant et al., 2021). Additionally, the use of diverse genetic material from landraces can mitigate the inbreeding depression observed in modern cultivars, thereby enhancing the genetic gain in future breeding efforts (Zahra et al., 2020).

6.2 Strategies for in situ and ex situ conservation

Effective conservation strategies are essential to preserve the genetic diversity of Myanmar’s rice landraces. In situ conservation, which involves maintaining rice varieties in their natural habitats, allows for the continued evolution and adaptation of these varieties to local environmental conditions. This method has been shown to retain most genetic diversity over time, as observed in on-farm conservation practices in other regions (Cui et al., 2019). Ex situ conservation, on the other hand, involves storing seeds in gene banks, which provides a safeguard against the loss of genetic material due to environmental changes or other threats. Both strategies are complementary and should be employed to ensure the long-term preservation of genetic resources. The high genetic diversity found in different ecosystems and areas within Myanmar underscores the importance of region-specific conservation efforts (Na et al., 2016).

6.3 Policy recommendations for genetic resource management

To effectively manage the genetic resources of Myanmar’s rice varieties, several policy recommendations can be made. A national framework should be established for systematically collecting and conserving rice landraces, integrating both in-situ and ex-situ strategies. This will ensure the preservation of genetic diversity and promote the sustainable use of rice germplasm for future breeding initiatives (Lin et al., 2023). Policies should encourage the use of traditional landraces in breeding programs to enhance the genetic base of modern cultivars and improve their resilience to environmental stresses (Ao et al., 2016; Zahra et al., 2020). There should be support for research initiatives aimed at characterizing the genetic diversity and population structure of rice varieties using advanced molecular markers, as this information is crucial for effective breeding and conservation efforts (Kumbhar et al., 2015; Thant et al., 2021). Collaboration with international organizations and research institutions can facilitate the exchange of knowledge and resources, thereby strengthening the overall genetic resource management framework. By implementing these strategies, Myanmar can safeguard its rich genetic heritage in rice and leverage it to develop improved rice varieties that meet future agricultural challenges. These policy measures will ensure that the genetic diversity of Myanmar’s rice is not only preserved but also effectively utilized for the benefit of current and future generations.

7 Challenges and Future Directions

7.1 Limitations of current studies

The exploration of genetic diversity within Myanmar’s core landrace rice varieties has faced several notable challenges. One primary limitation is the lack of comprehensive, high-resolution genomic data. Many studies rely on traditional phenotypic assessments and limited genetic markers, which may not capture the full extent of genetic variability. Additionally, there is a significant gap in the geographic and ecological coverage of sampled populations. Many landrace varieties, especially those from remote or less accessible regions, remain underrepresented in genetic analyses (Win et al., 2019).

Another critical issue is the inconsistency in methodological approaches, making it difficult to compare findings across different studies. Variability in DNA extraction techniques, marker systems, and data analysis methods can lead to discrepancies in results and interpretations (Tun et al., 2021). Furthermore, there is often limited collaboration and data sharing between local researchers and international research communities, which hampers the integration of local knowledge and resources into broader genetic studies (Aung et al., 2020).

7.2 Emerging technologies and approaches

Recent advancements in genomic technologies offer promising avenues to overcome these limitations. High-throughput sequencing technologies, such as whole-genome sequencing and genotyping-by-sequencing (GBS), provide detailed insights into genetic diversity at a much finer scale than traditional methods (He et al., 2019). These technologies can uncover rare alleles and structural variations that significantly contribute to the adaptability and resilience of rice landraces.

The integration of phenomic tools, including high-throughput phenotyping platforms and remote sensing technologies, can enhance our understanding of the genotype-phenotype relationship in diverse environments (Yang et al., 2021). Bioinformatics advancements, such as machine learning algorithms, are also pivotal in managing and analyzing large-scale genomic data, facilitating the identification of key genetic loci associated with desirable traits (Wang et al., 2020). The implementation of participatory breeding programs, where farmers and local communities are actively involved in the selection and breeding process, has shown great potential. This approach ensures that the developed varieties meet the specific needs and preferences of local farmers while preserving genetic diversity (Khush et al., 2018).

7.3 Future research priorities

Future research should prioritize the collection and conservation of landrace varieties from underrepresented regions to ensure a comprehensive genetic repository. Establishing a centralized, accessible database for genetic information and associated phenotypic data will be crucial for fostering collaboration and data sharing among researchers globally.

Further efforts should focus on the application of advanced genomic tools to conduct association studies that link genetic variants with agronomic traits, such as yield, stress tolerance, and nutritional quality. This knowledge can drive the development of improved rice varieties through molecular breeding techniques. Exploring the epigenetic mechanisms underlying trait expression in rice landraces could provide new insights into the adaptability and resilience of these varieties. Investigating the role of DNA methylation, histone modifications, and non-coding RNAs in regulating gene expression under various environmental conditions will be a critical area of research (Li et al., 2021). Integrating socio-economic studies with genetic research will be essential to understand the impact of breeding programs on local communities and to ensure the sustainable use and conservation of genetic resources. Engaging with policymakers to develop supportive frameworks for the protection of traditional knowledge and genetic resources is also paramount (Bhullar and Gruissem, 2019).

8 Concluding Remarks

The genetic diversity of Myanmar’s core landrace rice varieties represents a critical reservoir of traits essential for the resilience and sustainability of rice cultivation. Our study has highlighted the significant genetic variability within these landraces, which has been shaped by diverse agro-ecological conditions and traditional farming practices. However, current studies face limitations, including insufficient high-resolution genomic data, inconsistent methodologies, and inadequate geographic and ecological coverage of sampled populations. Despite these challenges, recent advancements in genomic technologies and participatory breeding approaches present promising opportunities for more comprehensive and effective genetic diversity studies.

To advance genetic diversity studies in Myanmar, it is imperative to prioritize the collection and conservation of underrepresented landrace varieties. Establishing a centralized, accessible database for genetic and phenotypic data will facilitate better collaboration and data sharing among researchers. The application of advanced genomic tools, such as whole-genome sequencing and genotyping-by-sequencing, should be expanded to conduct detailed association studies linking genetic variants with key agronomic traits.

Exploring the epigenetic mechanisms underlying trait expression and integrating socio-economic studies with genetic research will further enhance our understanding of the adaptability and resilience of rice landraces. Engaging policymakers to develop supportive frameworks for the protection of traditional knowledge and genetic resources is also crucial for the sustainable use and conservation of these valuable genetic resources.

The genetic diversity inherent in Myanmar’s core landrace rice varieties offers immense potential for enhancing the resilience and productivity of rice crops in the face of climate change and other challenges. By addressing current limitations and leveraging emerging technologies and approaches, researchers can unlock the full potential of these landraces. This will not only contribute to the sustainable development of Myanmar’s rice agriculture but also provide valuable insights for global rice breeding efforts. The continued study and conservation of these genetic resources are vital for ensuring food security and agricultural sustainability in the future.

Acknowledgments

We extend our sincere thanks to two anonymous peer reviewers for their invaluable feedback on the initial draft of this paper, whose critical evaluations and constructive suggestions have greatly contributed to the improvement of our manuscript.

Funding

This work was supported by the grants from the Central Leading Local Science and Technology Development Project (grant nos. 202207AA110010) and the Key and Major Science and Technology Projects of Yunnan (grant nos. 202202AE09002102).

Conflict of Interest Disclosure

The authors affirm that this research was conducted without any commercial or financial relationships that could be construed as a potential conflict of interest.

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