Rice Genomics and Genetics 2024, Vol.15, No.3, 132-141 http://cropscipublisher.com/index.php/rgg 137 5.3 Nutritional quality and grain characteristics The nutritional quality and grain characteristics of rice are also significantly influenced by the alleles derived from wild rice species. Wild rice relatives contain a wealth of genetic diversity that can be tapped to improve the nutritional profile of cultivated rice. For example, the introgression of alleles from wild rice has led to the development of rice varieties with enhanced grain size, pericarp color, and kernel color, which are important for both consumer preference and nutritional value (Zhang et al., 2022). Additionally, the pan-genome analysis of wild soybean, a close relative of rice, has revealed genes associated with seed composition and organ size, suggesting that similar approaches could be applied to rice to enhance its nutritional quality (Li et al., 2014). The identification of these beneficial alleles and their incorporation into breeding programs hold great promise for improving the overall quality of rice grains (Kamboj et al., 2020). The utilization of wild rice alleles has a profound impact on the agronomic traits of cultivated rice, including yield enhancement, stress tolerance, and nutritional quality. The integration of these alleles through advanced genomic and breeding techniques offers a sustainable approach to meeting the growing global food demand and ensuring food security in the face of environmental challenges. 6 Case Studies of Successful Utilization 6.1 Examples of wild alleles in cultivated rice The utilization of wild rice alleles has significantly contributed to enhancing disease resistance in cultivated rice varieties. For instance, Indian rice landraces have been found to harbor a diverse array of blast resistance genes. A study identified twenty-four significant blast resistance gene loci in landraces from various rice ecologies in India, with some landraces containing up to nineteen resistance genes. These genes have been crucial in developing rice varieties with enhanced resistance to blast disease, a major threat to rice production. Additionally, the genetic diversity within these landraces provides a valuable resource for future genomic studies and rice improvement strategies aimed at disease resistance (Yadav et al., 2019). Wild rice alleles have also been instrumental in improving abiotic stress tolerance in cultivated rice. For example, the introgression of salt-tolerant genes from wild rice into cultivated varieties has shown promising results. A study on the salt-tolerant line DJ15, derived from a cross between Dongxiang wild rice and the cultivated variety Ningjing16, identified several quantitative trait loci (QTL) associated with salt tolerance. These QTLs, particularly qST1.2 and qST6, have been shown to significantly enhance salt tolerance in rice, demonstrating the potential of wild rice genes in improving abiotic stress tolerance (Quan et al., 2018). Moreover, the genetic diversity analysis of stress-tolerant rice genotypes has revealed the presence of alleles that contribute to tolerance against various abiotic stresses, such as drought and submergence, further highlighting the importance of wild rice alleles in breeding programs (Islam et al., 2012). 6.2 Comparative analysis of cultivars with wild alleles Comparative studies of rice cultivars with and without wild alleles have provided insights into the benefits of utilizing wild genetic resources. For instance, the salt-tolerant line DJ15, which contains wild rice alleles, exhibited superior performance under salt-stress conditions compared to its cultivated parent, Ningjing16. This demonstrates the effectiveness of wild alleles in enhancing stress tolerance (Quan et al., 2018). Similarly, the genetic diversity analysis of aromatic and quality rice landraces from North-Eastern India has shown that these landraces possess unique alleles that contribute to their adaptation to local environmental conditions. These alleles can be harnessed to improve the stress tolerance and quality traits of modern rice cultivars (Roy et al., 2015). 6.3 Lessons learned from past successes The successful utilization of wild rice alleles in cultivated varieties has provided several key lessons for future breeding programs. Firstly, the genetic diversity present in wild rice and landraces is a valuable resource that can be leveraged to address various biotic and abiotic stresses. Studies have shown that landraces and wild relatives harbor unique alleles that are not present in modern cultivars, making them essential for broadening the genetic base of cultivated rice (Mammadov et al., 2018). The integration of modern molecular and genomic technologies
RkJQdWJsaXNoZXIy MjQ4ODYzNA==