Genome-wide investigation and expression analysis of the AP2/ERF family for selection of agarwood-related genes in Aquilaria sinensis (Lour.) Gilg.

Aquilaria sinensis is an important non-timber tree species for producing high-value agarwood, which is widely used as a traditional medicine and incense. Agarwood is the product of Aquilaria trees in response to injury and fungal infection. The APETALA2/ethylene responsive factor (AP2/ERF) transcription factors (TFs) play important roles in plant stress responses and metabolite biosynthesis. In this study, 119 AsAP2/ERF genes were identified from the A. sinensis genome and divided into ERF, AP2, RAV, and Soloist subfamilies. Their conserved motif, gene structure, chromosomal localization, and subcellular localization were characterized. A stress/defense-related ERF-associated amphiphilic repression (EAR) motif and an EDLL motif were identified. Moreover, 11 genes that were highly expressed in the agarwood layer in response to whole-tree agarwood induction technique (Agar-Wit) treatment were chosen, and their expression levels in response to methyl jasmonate (MeJA), salicylic acid (SA), or salt treatment were further analyzed using the quantitative real time PCR (qRT-PCR). Among the 11 genes, eight belonged to subgroup B-3. All 11 genes were significantly upregulated under salt treatment, while eight genes were significantly induced by both MeJA and SA. In addition, the gene clusters containing these upregulated genes on chromosomes were observed. The results obtained from this research not only provide useful information for understanding the functions of AP2/ERF genes in A. sinensis but also identify candidate genes and gene clusters to dissect their regulatory roles in agarwood formation for future research.

[Analysis and suggestions on harvest period standards of plant medicinal materials in 2020 edition of Chinese Pharmacopoeia].

The improvement of the harvest period standards is critical in the quality control of Chinese medicinal materials. The present study statistically analyzed the harvest period standards of plant medicinal materials in the 2020 edition of Chinese Pharmacopoeia(Vol.Ⅰ) and put forward the existing problems and suggestions based on herbal records and modern research to provide references for the improvement of the standards. According to the statistical analysis, in 499 types of plant medicinal materials, harvest period standards are recorded under 486 types, accounting for 97.4%, and are lacking in the remaining. Only one medicinal material(Stellariae Radix) is recorded with the standard of the harvest year. The standards of the harvest season and phenological period are recorded under 233 types, accounting for 46.7%. For 237 types, only harvest season is specified, accounting for 47.5%, and for 15 types, only harvest phenological period is specified, accounting for 3.0%. Among 222 types mainly derived from cultivation and 51 types from wild resources and cultivation, only 11 types are recorded with harvest period of cultivated products. Only Stellariae Radix is recorded with the harvest period standards for the wild and cultivated products separately. The harvest period standards of plant medicinal materials with different medicinal parts have certain rules to follow. The main problems about the harvest period standards are discovered. Specifically, no harvest period standards are recorded under 13 types of plant medicinal materials. Almost all perennial cultivated medicinal materials are not recorded with harvest year standard. No phenological period standard is found under 250 types of plant medicinal materials. There is no clear distinction between the harvest period standards of cultivated and wild products. The evidence for harvest period standards of 26 types of plant medicinal materials that can be harvested all year round is insufficient. As a result, it is proposed to strengthen basic research in response to the above-mentioned problems and improve the harvest period standards as soon as possible to ensure the quality of Chinese medicinal materials.