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Gene editing is a new genetic engineering technology that uses sequence-specific nucleases to insert, delete, or replace nucleic acid base(s) of the target gene, or introduce exogenous DNA sequences at a specific site in the genome of an organism to achieve the desired modification. Currently, the CRISPR/Cas system is the most widely used genome editing technology because it is relatively simple with high editing efficiency. In this review, we discuss the CRISPR/Cas system's application and its current limitations in rice breeding. Also, we elaborate on possible improved methods regarding its mechanism and development history. [ABSTRACT FROM AUTHOR]

Over half of the world's population relies on rice as their staple food. The brown planthopper (Nilaparvata lugens Stål, BPH) is a significant insect pest that leads to global reductions in rice yields. Breeding rice varieties that are resistant to BPH has been acknowledged as the most cost-effective and efficient strategy to mitigate BPH infestation. Consequently, the exploration of BPH-resistant genes in rice and the development of resistant rice varieties have become focal points of interest and research for breeders. In this review, we summarized the latest advancements in the localization, cloning, molecular mechanisms, and breeding of BPH-resistant rice. Currently, a total of 70 BPH-resistant gene loci have been identified in rice, 64 out of 70 genes/QTLs were mapped on chromosomes 1, 2, 3, 4, 6, 8, 10, 11, and 12, respectively, with 17 of them successfully cloned. These genes primarily encode five types of proteins: lectin receptor kinase (LecRK), coiled-coil-nucleotide-binding-leucine-rich repeat (CC-NB-LRR), B3-DNA binding domain, leucine-rich repeat domain (LRD), and short consensus repeat (SCR). Through mediating plant hormone signaling, calcium ion signaling, protein kinase cascade activation of cell proliferation, transcription factors, and miRNA signaling pathways, these genes induce the deposition of callose and cell wall thickening in rice tissues, ultimately leading to the inhibition of BPH feeding and the formation of resistance mechanisms against BPH damage. Furthermore, we discussed the applications of these resistance genes in the genetic improvement and breeding of rice. Functional studies of these insect-resistant genes and the elucidation of their network mechanisms establish a strong theoretical foundation for investigating the interaction between rice and BPH. Furthermore, they provide ample genetic resources and technical support for achieving sustainable BPH control and developing innovative insect resistance strategies. [ABSTRACT FROM AUTHOR]

Invasive ants threaten China's ecosystems and agriculture. Our review highlights the challenges faced and diverse strategies employed to combat these invaders, emphasizing the importance of international cooperation for safeguarding the environment and public well-being. [Display omitted] • Ecological & Economic Challenges of Exotic Ant Invasion in China. • In-Depth Analysis of China's Struggle with Exotic Ants. • Factors Behind Introduction & Establishment of Exotic Ants. • National Responses: Capacity Building, Research, Legislation. • Addressing Limitations, Enhancing Ant Invasion Strategies. The invasion of exotic ant species in China presents significant challenges to ecosystems, agriculture, and the economy. This paper provides an in-depth analysis of China's ongoing battle with exotic ants, examining the factors contributing to their introduction and establishment. It explores the responses implemented by the decision makers, including capacity building, establishment of research institutions, and legislative measures. Limitations and gaps in the current strategies are identified, highlighting the need for regional collaboration, increased awareness, and strengthened early detection and response systems. Furthermore, the paper emphasizes the importance of conducting research to understand various exotic ant species' ecological and economic impacts, facilitating the development of targeted and effective management approaches. By adopting a comprehensive and coordinated approach, China can mitigate the impacts of ant invasions and safeguard its biodiversity, agriculture, and economy. This analysis underscores the significance of collective efforts in addressing the ongoing battle with exotic ants and preserving the well-being of ecosystems, economies, and the society. [ABSTRACT FROM AUTHOR]

Summary: Bacterial leaf streak (BLS) is a major bacterial disease of rice. Utilization of host genetic resistance has become one of the most important strategies for controlling BLS. However, only a few resistance genes have been characterized. Previously, a recessive BLS resistance gene bls1 was roughly mapped on chromosome 6. Here, we further delineated bls1 to a 21 kb region spanning four genes. Genetic analysis confirmed that the gene encoding a mitogen‐activated protein kinase (OsMAPK6) is the target of the allelic genes BLS1 and bls1. Overexpression of BLS1 weakened resistance to the specific Xanthomonas oryzae pv. oryzicola (Xoc) strain JZ‐8, while low expression of bls1 increased resistance. However, both overexpression of BLS1 and low expression of bls1 could increase no‐race‐specific broad‐spectrum resistance. These results indicate that BLS1 and bls1 negatively regulate race‐specific resistance to Xoc strain JZ‐8 but positively and negatively control broad‐spectrum resistance, respectively. Subcellular localization demonstrated that OsMAPK6 was localized in the nucleus. RGA4, which is known to mediate resistance to Xoc, is the potential target of OsMAPK6. Overexpression of BLS1 and low expression of bls1 showed increase in salicylic acid and induced expression of defense‐related genes, simultaneously increasing broad‐spectrum resistance. Moreover, low expression of bls1 showed increase an in jasmonic acid and abscisic acid, in company with an increase in resistance to Xoc strain JZ‐8. Collectively, our study provides new insights into the understanding of BLS resistance and facilitates the development of rice host‐resistant cultivars. Significance Statement: A recessive bacterial leaf streak resistance gene bls1, which encodes a mitogen‐activated protein kinase (OsMAPK6), was cloned from common wild rice. The gene bls1 and its dominant allele BLS1 negatively regulate race‐specific resistance to Xanthomonas oryzae pv. oryzicola strain JZ‐8, but negatively and positively control broad‐spectrum resistance, respectively. [ABSTRACT FROM AUTHOR]