过表达三七 PnSS 基因调控 马铃薯对交链格孢引起的早疫病抗性.

[Objective] The paper aimed to study the effect of overexpression of Panax notoginseng PASS gene on early blight resistance in potato. [Method] The PASS gene was cloned from the leaves of P. notoginseng and a phylogenetic tree of P. notoginseng PnSS and its homologs was constructed using neighbor-joining method. Potato Jianchuan hong' was transformed using Agrobacterium mediated method. Two transgenic lines were randomly selected and inoculated with the pathogen Alternaria alternata under natural conditions. The disease index was quantified, and the expression levels of the auxin synthesis gene StYUCCAS and the auxin efflux carrier encoding genes StPIN1 and StPIN2 were detected using PCR. [Result] The PASS gene was cloned from P. notoginseng, and the phylogenetic tree showed that the P. notoginseng PnSS and its P. ginseng homologous were in the same cluster, but was in a different cluster with its Solanaceae homologous. After the transformation of P. notoginseng PASS gene into potato, 12 transgenic lines were obtained. Two lines were randomly selected and inoculated with A. alternata. It was found that transgenic potato plants expressing PaSS showed resistance to early blight. Furthermore, the transgenic potatoes showed a decreased levels of StYUCCA8 and StPIN2 before and after the plants inoculated with A. alternata, and the expression level of SIPINI increased before transgenic plants were inoculated with A. alternata, while the expression level decreased after inoculation with A. alternata. [Conclusion] Overexpression of the PASS gene decreases the expression levels of auxin synthesis and auxin efflux carriers-related genes to promote the potato resistance to early blight, which establishes a theoretical basis for potato breeding to obtain potato line resistance to early blight using PaSS gene. [ABSTRACT FROM AUTHOR]