Abstract:Based on the data of brown planthopper (Nilaparvata lugens (Stal)) and meteorological factors including temperature and precipitation in the Quanzhou region of Guangxi Province from 1979 to 2023, this study utilises Sen's slope, wavelet analysis, M-K trend, and mutation testing to analyse variation characteristics of the Nilaparvata lugens's phenological periods and its response to climate change in this region over the past 45 years. The results show that the initial appearance date shows an early trend at a rate of 0.43 days per year (p<0.05), and the final disappearance date and residence time show a delayed or prolonged trend at rates of 0.42 days per year and 0.85 days per year (p<0.01) respectively. No variation occurs in the phenological periods, and they remain relatively stable over time. The initial appearance date, final disappearance date, and duration of stay undergo mutations in 2009, 2003, and 2007, respectively. There are also multiple periodic variation characteristics. The first main period of the initial appearance date is 26 years, while the first main period of the final disappearance date and duration of stay is 28 years. The average temperatures in spring, summer, and autumn have increased extremely significantly and undergo mutations in 2001, 2021, and 2012, respectively. Seasonal precipitation has large inter-annual fluctuation and the change trend is not obvious. The significant increase in temperature in different seasons has a profound impact on the ecological environment. The large fluctuations in seasonal precipitation make the water environment more variable, which in turn affects the living conditions of the brown planthopper. Although the trend of precipitation change is not clear, its inter-annual variability still poses challenges to the adaptation of the brown planthopper. The initial appearance date has a highly significant response to spring temperature, and a warm spring can lead to an earlier initial appearance date. The final disappearance date is positively correlated with the autumn temperature element, and a warm autumn will make the final disappearance date of brown planthoppers later. Warm spring and warm autumn both prolong the staying time of brown planthoppers. The initial appearance date is negatively correlated with the precipitation in March, and the final disappearance date is positively correlated with the precipitation and the number of days in November. This shows that temperature and precipitation in specific seasons have specific regulatory effects on the phenological period of brown planthoppers. The relationship between temperature and phenological period reflects the direct impact of thermal conditions on the growth and development rhythm of brown planthoppers. The correlation between precipitation and phenological period indicates that water availability also plays an important role in determining the key life cycle nodes of brown planthoppers.