Effects of climate change and crop planting structure on the abundance of cotton bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae)

Abstract

The interactions between plants and insects play an important role in ecosystems. Climate change and cropping patterns can affect herbivorous pest insect dynamics. Understanding the reasons for population fluctuations can help improve integrated pest management strategies. Here, a 25‐year dataset on climate, cropping planting structure, and the population dynamics of cotton bollworms (Helicoverpa armigera) from Bachu County, south Xinjiang, China, was analyzed to assess the effects of changes in climate and crop planting structure on the population dynamics of H. armigera. The three generations of H. armigera showed increasing trends in population size with climate warming, especially in the third generation. The relative abundances of the first and second generations decreased, but that of the third generation increased. Rising temperature and precipitation produced different impacts on the development of different generations. The population numbers of H. armigera increased with the increase in the non‐Bacillus thuringiensis (Bt) cotton‐planted area. Asynchrony of abrupt changes existed among climate change, crop flowering dates, and the phenology of H. armigera moths. The asynchronous responses in crop flowering dates and phenology of H. armigera to climate warming would expand in the future. The primary factors affecting the first, second, and third generations of moths were Tmean in June, the last appearance date of the second generation of moths, and the duration of the third generation of moths, respectively. To reduce the harm to crops caused by H. armigera, Bt cotton should be widely planted.

Temperature-dependent development and survival of an invasive genotype of wheat curl mite, Aceria tosichella

“…This precise information about temperature-dependent life-history traits informs planning for complex, long-term studies and should thus accelerate progress. In the field, such data enable improved estimation of intra-specific demographics for ecological and host-pest synchrony studies (Pulatov et al 2016 ; Huang and Hao 2020 ). It is important to note that the study presented here was performed under laboratory conditions designed specifically to maintain minute phytophagous arthropods; in this case, mites were reared on plant fragments placed on an artificial medium.…”

Effects of climate change on different geographical populations of the cotton bollworm Helicoverpa armigera (Lepidoptera, Noctuidae)

“…In addition to climate factors, the crop planting structure was another important influencing factor. When the planting percentage of non‐ Bt cotton is over 50%, a substantial increase in cotton bollworm number may be observed (Huang & Hao, 2020 ); thus, the number of H . armigera moths in Maigaiti sharply increased.…”

Scientific review of the impact of climate change on plant pests

“…Meta-analyses of published data sets have been performed to search for general patterns in the responses of specific pests to differences in climate variables (Koricheva and Larsson, 1998;Massad and Dyer, 2010;Vila et al, 2021). In addition, long-term data sets from field observations have been used to study climate-change effects that are already apparent owing to the warming in recent decades (Altermatt, 2010;Huang and Hao, 2020;Jeger and Pautasso, 2008). Such long-term data sets can serve as a suitable baseline for future studies (Huang and Hao, 2020;Robinet and Roques, 2010) because they can help researchers distinguish impacts due to climate change from those due to other factors (Garrett et al, 2016(Garrett et al, , 2021.…”

“…In addition, long-term data sets from field observations have been used to study climate-change effects that are already apparent owing to the warming in recent decades (Altermatt, 2010;Huang and Hao, 2020;Jeger and Pautasso, 2008). Such long-term data sets can serve as a suitable baseline for future studies (Huang and Hao, 2020;Robinet and Roques, 2010) because they can help researchers distinguish impacts due to climate change from those due to other factors (Garrett et al, 2016(Garrett et al, , 2021. Attempts to improve estimates of climate-warming effects on insects have been made by combining data from long-term data sets, large-scale experiments and computer modelling (Diamond, 2018;Grünig et al, 2020;Lehmann et al, 2020).…”

“…Long-term weather records are necessary and, if available, other long-term data sets to search for other possible reasons for observed changes (particularly in managed systems). Huang and Hao, 2020;Palmer et al, 2017.…”