Molecular Entomology 2024, Vol.15, No.1, 32-42 http://emtoscipublisher.com/index.php/me 35 gene pool and the continuous evolution of virulent insect biotypes (Dash, 2020). Despite these challenges, conventional breeding remains a cornerstone of integrated pest management strategies, providing an ecologically viable approach to pest control (Dash, 2020). 2.2 Marker-assisted selection Marker-assisted selection (MAS) has revolutionized the breeding of insect-resistant rice varieties by enabling the precise identification and incorporation of resistance genes. This technology uses molecular markers linked to resistance traits to facilitate the selection process, thereby increasing the efficiency and accuracy of breeding programs. For example, MAS has been used to introgress resistance genes against gall midge, planthoppers, and leafhoppers into elite rice varieties (Bentur et al., 2021). The combined approach of marker-assisted forward and backcross breeding has also been employed to improve the Indian rice variety Naveen, resulting in lines with enhanced resistance to multiple biotic stresses, including blast, bacterial blight, and gall midge (Ramayya et al.,2021). These advancements highlight the potential of MAS to develop rice varieties with durable and multiple pest resistance (Bentur et al., 2021). 2.3 Genetic engineering Genetic engineering has opened new avenues for developing rice varieties with enhanced resistance to specific insect pests. Advances in this field include the use of RNA interference (RNAi) and CRISPR-based genome editing techniques. RNAi-based gene silencing has shown promise in conferring resistance to pests such as the brown planthopper and yellow stem borer (Figure 2) (Bentur et al., 2021). Additionally, CRISPR technology is being explored to target insect susceptibility genes in rice, offering a novel approach to pest control. Transformation of rice plants with insecticidal genes has also been a proven technology, although no insect-resistant transgenic rice cultivars are currently commercially available. The identification and cloning of resistance genes from wild rice species, such as the novel Bph38 gene from Oryza rufipogon, further exemplify the potential of genetic engineering in enhancing pest resistance (Yang et al., 2020). These advances underscore the importance of genetic engineering in developing next-generation insect-resistant rice varieties (Yang et al., 2020). The findings of Bentur et al., (2020) shows the induction of host gene silencing in insects by siRNA approach. The process starts with the integration of transgenic fragments (siRNA cassettes) specifically targeting insect genes into the rice genome, demonstrating the application of gene editing technology between plants and insects, and the use of siRNA function to regulate gene expression, which is of research value, and which can alter plant insect resistance or nutritional value as a means of biocontrol. However, there are potential risks associated with this technology, such as genetic drift or affecting non-target species.This mechanism demonstrates the potential of using transgenic plants to induce gene silencing in pests, providing a biotechnological approach for pest control.. By integrating conventional breeding, marker-assisted selection, and genetic engineering, researchers can develop rice varieties with robust and durable resistance to insect pests, thereby contributing to sustainable pest management and improved crop yields. 3 Case Studies 3.1 Successful Modifications Several case studies have demonstrated the successful genetic modification of rice to enhance resistance to specific insect pests. One notable example is the development of "multi-resistance rice" (MRR) through a transgene stacking system. This approach involved the assembly of multiple resistance genes, including those for glyphosate tolerance, lepidopteran pest resistance, brown planthopper resistance, bacterial blight resistance, and rice blast resistance. The modified rice variety, derived from the widely used japonica rice cultivar Zhonghua 11, exhibited significantly improved resistance to these pests and diseases, resulting in higher yields under natural field conditions (Li et al., 2020). Another successful case involves the identification and cloning of the Bph37 gene, which confers resistance to brown planthopper (BPH). This gene was identified through genome-wide
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