Whole Transcriptome Analysis Resulted in the Identification of Chinese Sprangletop (Leptochloa Chinensis) Genes Involved in Cyhalofop-Butyl Resistance
Abstract Background Chinese sprangletop [Leptochloa chinensis (L.) Nees] is an annual invasive weed, which can often be found in paddy fields. Cyhalofop-butyl is a specialized herbicide which is utilized to control L. chinensis. However, in many areas, L. chinensis has become resistant to this key herbicide due to its continuous long-term use. Results In this study, we utilized a resistant (LC18002) and a sensitive (LC17041) L. chinensis populations previously identified in our laboratory, which were divided into nine different treatment groups. We then employed whole transcriptome analysis to identify candidate genes which may be involved in cyhalofop-butyl tolerance. This analysis resulted in the identification of eight possible candidate genes, including six cytochrome P450 monooxygenase genes and two ATP-binding cassette transporter genes. We then carried out a phylogenetic analysis to identify homologs of the differentially expressed P450 genes. This phylogenetic analysis indicated that every genes have close homologs in pattern species, some of which have been implicated in non-target site resistance (NTSR). Conclusions This study is the first to use whole transcriptome analysis to identify herbicide non-target resistance genes in L. chinensis. The differentially expressed genes represent promising targets for better understanding herbicide tolerance in L. chinensis. The eight genes belonging to classes already associated in herbicide tolerance may play important roles in the metabolic resistance of L. chinensis to cyhalofop-butyl, although the exact mechanisms require further study.