Lihui Liu

As a tropical fruit of considerable economic importance, passionfruit (Passiflora edulis Sims) is extensively cultivated in the tropical and subtropical regions of China; however, the widespread incidence of viral diseases has significantly hampered the safety of its production. Rapid, sensitive, and visual detection of plant viruses is essential to effectively prevent and manage these viral diseases. In this study, we developed a visual detection system (displaying under blue light or UV) utilizing reverse transcription recombinase-aided amplification (RT-RAA) in conjunction with CRISPR/Cas12a to detect three viruses harmful to passionfruit production: telosma mosaic virus (TelMV), East Asian passiflora virus (EAPV), and passiflora mottle virus (PaMoV). Within this system, the optimal primer concentration for the RT-RAA reaction was determined to be 0.4 μM for all three viruses, with an optimal reaction temperature of 37 °C. The optimal reaction times were established as 20 min for TelMV, 15 min for EAPV, and 30 min for PaMoV. The entire detection process could be completed within 30 min without the need for sophisticated equipment or instruments. For TelMV and EAPV, the detection system demonstrated the capability to detect samples at a dilution of 10⁶, representing an approximately 10⁴-fold improvement over RT-PCR, while for PaMoV, it could identify samples at a dilution of 10⁶, representing an approximately 10²-fold improvement over traditional RT-PCR methods. These results confirm the successful development of the CRISPR/Cas12a-based detection systems. Subsequently, the system was applied for in situ detection of the three target viruses in field settings, yielding results that were fully consistent with laboratory-based RT-PCR assays, a consistency which underscores the system’s strong potential for field application in detecting important crop viruses.

Southem rice black-streaked dwarf virus (SRBSDV), a fijivirus with a double-stranded RNA genome of 10 segments and 13 proteins, severely impairs rice growth and development. The functions of P8, one of the major coat proteins of SRBSDV, are still poorly understood. In this study, the SRBSDV-encoded P8 protein was used as bait in a yeast two-hybrid screen of a rice cDNA library, which identified an interaction between P8 and auxin response factor 15 (OsARF15). The interaction was then confirmed by GST pull-down (in vitro) and co-immunoprecipitation (Co-IP) (in vivo) assays. Truncated protein analysis further revealed that P8 primarily binds to the C-terminal region of OsARF15. Over-expression and knockout of OsARF15 rice plants were constructed and then inoculated by SRBSDV. The results showed that over-expression of OsARF15 promoted SRBSDV infection whereas its knockout enhanced virus resistance. Meanwhile, the effect of OsARF15 on root development was observed and found that knocking out OsARF15 significantly promoted the growth of rice roots at the seeding stage. These results demonstrate that the SRBSDV P8 protein facilitates viral infection by interacting with the C-terminal region of OsARF15. Our findings have further strengthened the role of P8 in the viral infection process.

The genus Petrocodon is uniquely distributed in karst areas and exhibits high floral morphological diversity. We assembled and characterized the complete chloroplast genomes of Petrocodon mirus X.Z.Shi, J.X.Fu & L.H.Yang 2024 and Petrocodon hancei (Hemsl. 1890) A.Weber & Mich.Möller 2011. The genome sizes are 153,547 bp and 153,294 bp, respectively. Phylogenetic analysis revealed that P. hancei is closely related to P. multiflorus, while the position of P. mirus remains unclear. These findings provide genomic resources for studying genetic diversity in Petrocodon and Gesneriaceae.

C₂₀H₁₈ClIN₂, monoclinic, P2₁/n (no. 14), a = 9.5271(19) Å, b = 16.936(3) Å, c = 12.012(2) Å, β = 105.06(3)°, V = 1871.5(7) ų, Z = 4, R_gt (F) = 0.0436, wR_ref (F ²) = 0.1396, T = 296(2) K. CCDC no.: 2059378

Diachasmimoorpha longicaudata (Ashmead, D. longicaudata) (Hymenoptera: Braconidae) is a solitary species of parasitoid wasp and widely used in integrated pest management (IPM) programs as a biological control agent in order to suppress tephritid fruit flies of economic importance. Although many studies have investigated the behaviors in the detection of their hosts, little is known of the molecular information of their chemosensory system. We assembled the first transcriptome of D. longgicaudata using transcriptome sequencing and identified 162,621 unigenes for the Ashmead insects in response to fruit flies fed with different fruits (guava, mango, and carambola). We annotated these transcripts on both the gene and protein levels by aligning them to databases (e.g., NR, NT, KEGG, GO, PFAM, UniProt/SwissProt) and prediction software (e.g., SignalP, RNAMMER, TMHMM Sever). CPC2 and MIREAP were used to predict the potential noncoding RNAs and microRNAs, respectively. Based on these annotations, we found 43, 69, 60, 689, 26 and 14 transcripts encoding odorant-binding protein (OBP), chemosensory proteins (CSPs), gustatory receptor (GR), odorant receptor (OR), odorant ionotropic receptor (IR), and sensory neuron membrane protein (SNMP), respectively. Sequence analysis identified the conserved six Cys in OBP sequences and phylogenetic analysis further supported the identification of OBPs and CSPs. Furthermore, 9 OBPs, 13 CSPs, 3 GRs, 4IRs, 25 ORs, and 4 SNMPs were differentially expressed in the insects in response to fruit flies with different scents. These results support that the olfactory genes of the parasitoid wasps were specifically expressed in response to their hosts with different scents. Our findings improve our understanding of the behaviors of insects in the detection of their hosts on the molecular level. More importantly, it provides a valuable resource for D. longicaudata research and will benefit the IPM programs and other researchers in this filed.