The tomato leaf miner, Tuta absoluta is a destructive pest of tomato. The leaf-mining activities of its larvae can cause significant yield losses. Real-time quantitative polymerase chain reaction (RT-qPCR) is commonly used to measure gene expression, and the selection of stable reference genes for calibration and standardization is critical for accurate use of RT-qPCR. We studied the stable expression of nine common housekeeping genes in T. absoluta. These were examined at different developmental stages, in larval tissues, as well as those induced by exposure to 20E and insecticides. Four dedicated algorithms (geNorm, BestKeeper, NormFinder, and ΔCt method) and online tool (RefFinder) were used to analyze and rank the tested reference genes. Based on the standardized gene expression data of target gene ecdysone receptor (EcR), the applicability of specific reference genes was verified. The results clarify that the optimal internal reference genes vary greatly under different experimental conditions. GAPDH and RPS11 were the best reference genes for developmental stages; RPL28 and RPL10 for different tissues; EF1α and RPL28 for 20E treatment; EF1α and RPL7A for insecticide treatments. The most suitable reference genes in all experimental conditions are EF1α and RPL28.

Microorganisms in the guts of insects enhance the adaptability of their hosts with different lifestyles, or those that live in different habitats. Tuta absoluta is an invasive pest that is a serious threat to tomato production in China. It has quickly spread and colonized Xinjiang, Yunnan and other provinces and regions. We used Illumina HiSeq next generation sequencing of the 16S rRNA gene to study and analyze the composition and diversity of the gut microbiota of three geographical populations of T. absoluta. At the phylum level, the most common bacteria in T. absoluta across all three geographical populations were Proteobacteria and Firmicutes. An uncultured bacterium in the Enterobacteriaceae was the dominant bacterial genus in the T. absoluta gut microbiotas. There were no significant differences in alpha diversity metrics among the Spanish, Yunnan and Xinjiang populations. The structures of the gut microbiota of the three populations were similar based on PCoA and NMDS results. The results confirmed that the microbial structures of T. absoluta from different regions were similar.

The frequency and amplitude of heat waves are predicted to increase under future climate change conditions. We still lack a detailed understanding of how changes in the frequency and amplitude of heat waves are linked to the life history traits and biocontrol efficiency of host-feeding parasitoids. In the present study, we simulated a series of heat waves as a function of amplitude and frequency to investigate the effects on the life history traits of the host-feeding parasitoid Eretmocerus hayati. We found that both the amplitude and frequency of heat waves significantly affected the adult phenotypes. In the low-amplitude heat wave group, the frequency of heat waves did not change the life history traits of the parasitoid; however, when the heat amplitude reached 42 °C, medium (four times/week) and high frequencies (seven times/week) of heat waves detrimentally affected these parameters. Hence, these findings suggest that to obtain optimal biological control with this parasitoid, we need to carefully monitor heat wave pattern (especially the amplitude and frequency) over the short term (usually 7–10 days) before releasing a host-feeding parasitoid.

Fusarium head blight (FHB) is a serious disease of wheat that threatens wheat production worldwide. In this study, high-throughput sequencing technology was used to analyze the rhizosphere soil microbial metagenomes of 4 wheat cultivars with different levels of resistance to FHB. The results showed that there were differences in the diversity, structure, and composition of rhizosphere microorganisms between resistant and sensitive varieties. The rhizosphere soil bacterial diversity of the resistant wheat varieties Su Mai 3 and Yang Mai 16 was higher than that of the susceptible wheat varieties Zheng Mai 9023 and Zhou Mai 20. The diversity of rhizosphere fungi in resistant varieties was lower than that in susceptible varieties, but the abundance was higher than that in susceptible varieties. Variety was found to alter the community structure of wheat rhizosphere microorganisms. Resistant varieties SM3 and YM16 and moderately susceptible variety ZM9023 had similar microbial community structure, while highly susceptible variety ZM20 was significantly different from other varieties. The study is aimed at analyzing the effects of wheat varieties of different resistance to FHB on the composition and abundance of rhizosphere soil microbial community to screen out bacteria or fungi that can be used to control FHB, providing the theoretical basis for FHB biological control.