Global warming-induced extreme high temperatures pose severe challenges to the adaptive evolution of invasive insects, while the thermotolerance response mechanisms of most invasive insects and the changes in their resident microorganism in response to high-temperature stress underexplored. This study systematically investigated the thermotolerance response mechanism of the major invasive pest Tuta absoluta (Tomato Leafminer) and the impact of short-term high-temperature stress on its resident microorganism (including gut, reproductive glands, mouthparts, etc.), particularly on the endosymbiont Wolbachia. Gradient heat shock experiments (26℃, 36℃, 44℃) revealed that 44℃ treatment for 3 hours significantly reduced female adult survival rate to 20.33%, while 36℃ had no significant effect; female adult lifespan showed no significant differences after different temperature treatments; the activities of three antioxidant enzymes (Catalase CAT, Peroxidase POD, and Superoxide Dismutase SOD) did not change significantly under high temperature, suggesting its thermotolerance does not rely on the traditional antioxidant system. 16S rRNA gene sequencing indicated that high temperature significantly altered the microbial community structure: Proteobacteria accounted for over 83.62%, the abundance of the symbiont Wolbachia in the high-temperature female adult group significantly increased to 70.40% (ambient temperature group < 42.18%), and microbial α-diversity (Shannon index decreased by 64%) and function were altered. KEGG analysis showed that microbiota pathways related to carbohydrate metabolism and energy metabolism were significantly activated under heat stress, accompanied by enrichment of antibiotic biosynthesis genes, implying that Wolbachia may enhance heat tolerance by regulating host energy homeostasis and suppressing pathogens. This study reveals the responses of T. absoluta and its resident microorganism to short-term high-temperature heat shock, laying a theoretical foundation for further investigation into the influence of symbiotic bacteria like Wolbachia on the thermotolerance of T. absoluta.

Root-knot nematodes (RKNs) are the most economically damaging plant-parasitic nematodes globally. Xinjiang, encompassing one-sixth of China’s landmass, currently lacks comprehensive data regarding the occurrence, distribution, and genetic variation of RKNs infecting vegetables within its borders. Hence, identifying RKNs species and genetic diversity is crucial for devising comprehensive management strategies. Between 2021 and 2023, we present a survey of 130 samples, collected from 86 counties across 14 cities in Xinjiang, China, aiming to comprehensively understand the occurrence, distribution, damage, and species of vegetable RKNs. The results indicated that 57 out of 130 samples collected from the regions of Hami, Tulufan, Ili, Bayingol, Hotan, Aksu, Kashgar, and Kizilsu in Xinjiang were infected by RKNs, suggesting an expansion of RKN disease in the vegetable-producing regions of Xinjiang. The infected vegetable roots were found to harbor Meloidogyne incognita and M. hapla, with M. incognita being the most prevalent species. A phylogenetic analysis of the COI region revealed significant evolutionary divergence between M. incognita populations from Xinjiang and those from southeastern provinces. Haplotype analysis of the COI gene revealed that M. incognita populations are categorized into three major lineages: Asia, Europe, and a combined lineage encompassing both America and Africa. Notable gene flow patterns were observed among M. incognita populations, with significant migrations from Europe and America to Asia, specifically from the southeastern China towards Xinjiang. This study’s findings indicate a consistent increase in the detrimental effects of vegetables production caused by RKNs in Xinjiang. Implementing effective prevention and control measures is crucial to mitigate the spread of RKNs.