Virtual human is the simulation of human under the synthesis of virtual reality,artificial intelligence,and other technologies.Modern virtual human technology simulates both the external characteristics and the internal emotions and personality of humans.The relationship between virtual human and human is a concrete expression of the modern symbiotic relationship between human and machine.This human-machine symbiosis can either be a fusion of the virtual human and the human or it can cause a split in the human itself.
The family Orchidaceae is of the most diverse taxon in the plant kingdom,and most of its members are highly valuable herbal medicines.Orchids have a unique mycorrhizal symbiotic relationship with specific fungi for carbohydrate and nutrient supplies in their whole lifecycle.The large-scale cultivation of the medicinal plant Gastodia elata is a successful example of using mycorrhizal symbiotic technology.In this review,we adopted G.elata and Dendrobium officinale as examples to describe the characteristics of orchid mycorrhiza and mycorrhizal benefits for host plants’growth and health(e.g.biotic and abiotic stress and secondary metabolite accumulation).The challenges in applying mycorrhizal technology to the cultivation of orchid medicinal plants in the future were also discussed.This review aims to serve as a theoretical guide for the cultivation of mycorrhizal technology in medicinal orchid plants.
Root nodule symbiosis(RNs)between legumes and rhizobia is a major source of nitrogen in agricultural systems.Effective symbiosis requires precise regulation of plant defense responses.The role of the defense hormone jasmonic acid(JA)in the immune response has been extensively studied.Current research shows that JA can play either a positive or negative regulatory role in RNS depending on its concentration,but the molecular mechanisms remain to be elucidated.In this study,we found that inoculation with the rhizobia Sm1021 induces the JA pathway in Medicago truncatula,and blocking the JA pathway significantly reduces the number of infection threads.Mutations in the MtMYc2 gene,which encodes a JA signaling master transcription factor,significantly inhibited rhizobia infection,terminal differentiation,and symbiotic cell formation.Combining RNA sequencing and chromatin immunoprecipitation sequencing,we discovered that MtMYc2 regulates the expression of nodule-specific MtDNF2,MtNAD1,and MtSymCRK to suppress host defense,while it activates MtDNF1 expression to regulate the maturation of MtNCRs,which in turn promotes bacteroid formation.More importantly,MtMYC2 participates in symbiotic signal transduction by promoting the expression of MtiPD3.Notably,the MtMYC2-MtiPD3 transcriptional regulatory module is specifically present in legumes,and the Mtmyc2 mutants are susceptible to the infection by the pathogen Rhizoctonia solani.Collectively,these findings reveal the molecular mechanisms of how the JA pathway regulates RNS,broadening our understanding of the roles of JA in plant-microbe interactions.
Da GuoJingrui LiPeng LiuYuzhan WangNa CaoXiangling FangTao WangJiangli Dong
