Calliptamus italicus L. is an important pest on the desert and semidesert steppes along the Sino-Kazakh border. To elucidate the molecular mechanism of its continuous outbreaks, we studied 11 different geographic populations of C. italicus to determine: 1) the complete sequences of the entire mitochondrial cytochrome oxidase subunit I (COI) and mitochondrial cytochrome oxidase subunit II (COII) genes, and 2) performed genetic diversity, differentiation, gene flow, and molecular variation analyses. Of the 11 populations, the Yining County (YNX) population had the highest haplotype diversity and Pi values. There are significant differences in Tajima’s D and Fu’s Fs (P < 0.05). The fixation index Fst values of the total C. italicus population were 0.03352, and its gene flow N_m values of the total C. italicus population were 15.32. Taken together, there were five main findings: 1) the current genetic differentiation of C. italicus arose within populations; 2) genetic exchange levels were high between geographical populations; 3) genetic variation level was low; 4) C. italicus populations likely expanded in recently, and 5) there was no significant correlation between genetic distance and geographic distance for any geographic population. Findings from this study indicate that frequent gene exchange between populations may enhance the adaptability of C. italicus along the Sino-Kazakh border, leading to frequent outbreaks.

Background: Calliptamus italicus is a dominant species in the desert and semi-desert grassland. It is widely distributed throughout many regions such as Asia, Europe, North Africa and the Mediterranean, and has enormous destructive potential for agriculture and animal husbandry. The C. italicus overwintering as eggs in the soil through diapause, and the cold tolerance of locust eggs is the key to their ability to survive the winter smoothly to maintain the population. Results: Transcriptome analysis of C. italicus eggs was carried out in this paper in constant low temperature acclimation, natural low temperature acclimation and room temperature. The differentially expressed genes related to cold tolerance were screened out, the differences in expression patterns under different low temperature acclimation were analyzed, and the genes in the significantly up-regulated pathways may play an important role in cold tolerance. The results show that different domestication modes can induce C. italicus eggs to express a large number of genes to alleviate low temperature damage, but C. italicus eggs are more sensitive to changes in temperature. Compared with the control, there are 8689 DEGs at constant low temperature and 14,994 DEGs at natural low temperature. KEGG analysis showed that DEGs were mainly enriched in pathways related to metabolism and biological systems under constant low temperature, and were mainly enriched in pathways related to biological systems and environmental information processing under natural low temperature. In addition, RNAi technology was used to further verify the regulation of genes in the significantly enriched up-regulated pathways on C. italicus eggs, and it was confirmed that the hatching rate of C. italicus eggs at low temperature was significantly reduced after interference. Conclusions: Transcriptome analysis of C. italicus eggs treated at different temperatures provided a theoretical basis for further understanding the adaptation mechanism of C. italicus eggs to low temperature. In addition, four potential RNAi target genes were verified in the eggs of C. italicus for the first time, providing new ideas for effective control of this species.

Grasshoppers (Acridoidea) are one of the most essential components of grassland ecosystems. They are mainly primary consumers and some of them, e.g., the Italian locust, may be very important pests. The main goal of this article is to discuss possible shifts in the species distribution relative to global and local changes. General patterns of latitudinal, longitudinal, and altitudinal distribution of its populations are revealed for the eastern part of its range (mainly from 70° E eastward). Data on its historic and modern localities with geographic coordinates were collected and analyzed. The Maxent approach was used to model species distribution. The comparative analysis shows there are no significant changes in its range. The analysis of altitudinal distribution over mountains of the region demonstrates no significant changes as well. The expected distribution of Calliptamus italicus based on the location points displays significant changes in areas suitable for the species and their evident associations with outbreak occurrences. The models created for 2021–2040 and 2041–2060 unveil that, in the future, the local parts of the Italian locust range may shift northward and north-eastward, but the main areas with suitable conditions for this species will remain almost the same.

The Hybrid Single Particle Lagrangian Integrated Trajectory Model and meteorological graphics software (Grads and ArcGIS) were used to analyze source areas and migratory trajectories of a population of Locusta migratoria migratoria (L.) (Orthoptera: Acrididae) in the Tacheng region of Xinjiang, China that borders with eastern Kazakhstan. The source areas of these locusts migrating into the Tacheng region are distributed near Lake Alakol, Lake Zaisan, eastern Lake Balkhash, the Irtysh River, and Ayaguz River in Kazakhstan. Locusts follow nine migratory trajectories in their invasion of Tacheng. On the respective migration dates, a westerly wind, northerly wind, or northwesterly wind, the latter being the prevailing wind direction, occurred at 950 hPa over the source areas. At migration heights of 300, 500, and 800 m above mean sea level, the air temperatures ranged from 25.0–31.0°C, 21.5–26.0°C, and 21.0–25.0°C, respectively. The concept of insect migration pattern in Central Asia is proposed, but a series of theoretical and empirical studies will be needed to provide support for this postulation.

Calliptamus italicus L. is a major migratory pest that often causes serious agricultural losses in the desert/semi‐desert steppe of Central Asia. The present study aims to understand the physiological factors that affect migration of C. italicus by examining the relationships between flight capacity, energy accumulation, ovarian development and Juvenile hormone (JH) titre. The results show that flight capacity decreases with age, being greatest among 2‐day‐old males and lowest among 13‐day‐old locusts. There is no significant correlation between energy accumulation and flight capacity, although JH titre is negatively correlated with flight capacity. Energy accumulation and flight capacity first increases then decreases in 1–13‐day‐old females. Glycogen accumulation is significantly correlated with flight speed, and triglyceride accumulation is significantly correlated with flight distance, duration and speed. Changes in JH titre in 1–13‐day‐old females show double titre peaks, which are negatively correlated with flight capacity. Seven‐day‐old C. italicus have the highest glycogen and triglyceride accumulation, greatest flight capacity, grade II ovarian development and lowest JH titre. By contrast, 13‐day‐old C. italicus have the lowest triglyceride accumulation, lowest flight capacity, grade IV ovarian development and lowest JH titre. Taken together, these findings demonstrate that there is a trade‐off between ovarian development and flight capacity of C. italicus .

Calliptamus italicus and Gomphocerus sibiricus are indicator species in Xinjiang’s low-altitude (700–1,900 m) and high-altitude (2,000–3,400 m) grasslands, respectively. C. italicus is tolerant to high-temperature stress, with its semilethal temperature (LT₅₀) being 10.5°C higher than that of G. sibiricus. The two locust species were subjected to high-temperature stress to explore the molecular mechanisms and differences in high temperature tolerance between the two locust species. Next, the next generation sequencing (NGS) data were mapped to reference transcripts obtained using single molecule real Time (SMRT) sequencing to construct a nonparameter transcriptome. The transcriptomic response of these two locust species displayed different patterns. C. italicus had 126 differentially expressed genes (DEGs), with 59 and 67 being significantly up-regulated and down-regulated, respectively. The heat shock protein (Hsp) genes were highly expressed upon two locust species exposure to high-temperature stress, with Hsp70 being expressed the most. G. sibiricus had 86 DEGs, of which 45 were significantly up-regulated and 41 significantly down-regulated. In addition, the expression of the key enzyme encoding gene Myo-inositol oxygenase (MIOX) in inositol degradation was the highest in G. sibiricus. In the KEGG pathway, the biological processes and metabolic pathways were the most enriched pathways in C. italicus and G. sibiricus, respectively. Moreover, the quantitative fluorescence results were consistent with the transcriptome results, implying that the transcriptome results were accurate. The findings in this study provide valuable information for future research exploring the evolution mechanisms of heat resistance in C. italicus and G. sibiricus.