Rice Genomics and Genetics 2025, Vol.16, No.1, 50-60 http://cropscipublisher.com/index.php/rgg 56 mainly starting from two directions: on the one hand, searching for germplasm resources with these excellent characteristics around the world, which is the most basic and important step; on the other hand, new technologies such as marker-assisted selection (MAS) and genetic modification are also gaining more and more attention (Zafar et al., 2020). After all, traditional breeding methods are slow to take effect, while molecular breeding can more accurately "install" the target traits into new varieties, greatly shortening the breeding cycle. In the final analysis, to cultivate rice that can truly adapt to the future climate, it may still rely on a combination of traditional methods and new technologies. 6.2 Gene editing approaches to enhance adaptive traits When it comes to newweapons in rice breeding, CRISPR/Cas9 gene editing technology is definitely a tough guy. The most powerful thing about this technology is that it can accurately "prune" genes related to stress resistance (Rasheed et al., 2021; Nascimento et al., 2023). For example, a recent study combined resistance genes such as PgHSF4 and p68, and the resulting rice was not only resistant to high temperatures, but also to salinity and oxidative stress (Sheela et al., 2023). However, gene editing alone is not enough, and you have to know which genes to edit first. At this time, QTL positioning comes in handy-by analyzing a large amount of data to find key quantitative trait loci (Raza et al., 2020; Liu et al., 2023). With these target genes, the efficiency of breeding heat-resistant rice can be greatly improved by using CRISPR technology for precise modification. Interestingly, although these new technologies look very "high-end", they still need to be combined with traditional breeding experience in actual operation. After all, rice's stress resistance is a complex trait that cannot be completely solved by simply changing one or two genes. 6.3 Agronomic practices to mitigate the impact of temperature and light stress Faced with increasingly frequent high temperatures and abnormal light, farmers actually have many practical coping strategies. Let's start with the simplest one - adjust the sowing time to avoid the hottest days, and then choose some varieties that are used to blooming in the morning (Khan et al., 2019), so that the rice can suffer less. However, these are not enough. Now agricultural technicians will also use some "little tricks", such as spraying specific plant hormones, or adding some special fertilizers and protective agents (Rasheed et al., 2021), which can help rice better resist the harsh environment. Interestingly, more sophisticated control methods have emerged in recent years. Through specific growth regulators and agronomic operations (Zafar et al., 2020), rice can be "trained" to adapt to environmental changes. Of course, if these traditional methods can be used in combination with new technologies such as gene editing, the effect will be better. After all, to cope with the big challenge of climate change, we still have to take a multi-pronged approach. 7 Knowledge Gaps and Future Research Directions 7.1 Unresolved questions in temperature and light sensing mechanisms Although a lot of research has been done on the response mechanism of rice to changes in light and temperature, there are still many mysteries to be solved. Take cold tolerance as an example. Scientists have discovered a strange phenomenon - light signals and biological clocks obviously affect cold tolerance, but how they specifically regulate related genes is still an unsolved mystery (Lu et al., 2020). Even more troublesome is the study of heat tolerance of reproductive tissues. Although some key sites have been found through QTL positioning (Raza et al., 2020), how these genes work specifically still needs further exploration. When it comes to plant hormones, it is even more complicated. Hormones such as auxin and ABA behave quite "changeable" under high temperatures (Sharma et al., 2021). The regulatory network they form is like a black box. We only see the input and output, and the process in between is still unclear. Filling these research gaps may help us breed more stress-resistant rice varieties. 7.2. Potential of integrating omics approaches To truly understand how rice copes with changes in temperature and light, a single research method is not enough. Genomics has indeed helped us find a number of QTL loci related to stress resistance (Lv et al., 2019; Raza et al., 2020), but knowing these alone is not enough. For example, transcriptome sequencing allows us to see
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