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PLIP lipases can initiate jasmonic acid (JA) biosynthesis. However, little is known about the transcriptional regulation of this process. In this study, an ERF transcription factor (CsESE3) was found to be co-expressed with all necessary genes for JA biosynthesis and several key genes for wax biosynthesis in transcriptomes of ‘Newhall’ navel orange. CsESE3shows partial sequence similarity to the well-known wax regulator SHINEs (SHNs), but lacks a complete MM protein domain. Ectopic overexpression of CsESE3in tomato (OE) resulted in reduction of fruit surface brightness and dwarf phenotype compared to the wild type. The OE tomato lines also showed significant increases in the content of wax and JA and the expression of key genes related to their biosynthesis. Overexpression of CsESE3in citrus callus and fruit enhanced the JA content and the expression of JA biosynthetic genes. Furthermore, CsESE3could bind to and activate the promoters of two phospholipases from the PLIP gene family to initiate JA biosynthesis. Overall, this study indicated that CsESE3could mediate JA biosynthesis by activating PLIPgenes and positively modulate wax biosynthesis. The findings provide important insights into the coordinated control of two defense strategies of plants represented by wax and JA biosynthesis.

Winter jujube (Ziziphus jujuba‘Dongzao’) is greatly appreciated by consumers for its excellent quality, but brand infringement frequently occurs in the market. Here, we first determined a total of 38 elements in 167 winter jujube samples from the main winter jujube producing areas of China by inductively coupled plasma mass spectrometer (ICP-MS). As a result, 16 elements (Mg, K, Mn, Cu, Zn, Mo, Ba, Be, As, Se, Cd, Sb, Ce, Er, Tl and Pb) exhibited significant differences in samples from different producing areas. Supervised linear discriminant analysis (LDA) and orthogonal projection to latent structures discriminant analysis (OPLS-DA) showed better performance in identifying the origin of samples than unsupervised principal component analysis (PCA). LDA and OPLS-DA had a mean identification accuracy of 87.84% and 94.64% in the testing set, respectively. By using the multilayer perceptron (MLP) and C5.0, the prediction accuracy of the models could reach 96.36% and 91.06%, respectively. Based on the above four chemometric methods, Cd, Tl, Mo and Se were selected as the main variables and principal markers for the origin identification of winter jujube. Overall, this study demonstrates that it is practical and precise to identify the origin of winter jujube through multi-element fingerprint analysis with chemometrics, and may also provide reference for establishing the origin traceability system of other fruits.