The Plant Growth-Promoting Fungus (PGPF) Alternaria sp. A13 Markedly Enhances Salvia miltiorrhiza Root Growth and Active Ingredient Accumulation under Greenhouse and Field Conditions.

Plant growth-promoting fungi (PGPF) have attracted considerable interest as bio-fertilisers due to their multiple beneficial effects on plant quantity and quality and their positive relationship with the ecological environment. Advancements in the development of PGPF for crops and economic plant cultivation applications have been achieved, but such improvements for the use of PGPF with popular medicinal herbs, such as Salvia miltiorrhiza, are rare. In this study, we collected S. miltiorrhiza specimens inhabiting wild, semi-wild, farmland and pot-cultured areas in the Henan province of China and isolated endophytes from the roots, shoots and leaves of these samples. Twenty-eight strains of the dominant genus Alternaria were identified and selected as candidate PGPF. Under greenhouse conditions, Alternaria sp. A13 simultaneously enhanced the dry root biomass and secondary metabolite accumulation of S. miltiorrhiza as the optimal PGPF of the 28 candidate isolates. To further assess the interaction between S. miltiorrhiza and Alternaria sp. A13, the effects on seedlings growth, active ingredient accumulation, and the activity of key enzymes for effective biosynthetic pathways were investigated over a period of six months under field conditions. Compared to uninoculated seedlings, S. miltiorrhiza seedlings colonised by Alternaria sp. A13 showed significant increment of 140% in fresh weight, 138% in dry weight, and enhancement in the contents of total phenolic acid, lithospermic acids A and B (LAA and LAB, respectively) of 210%, 128% and 213%, respectively. Examination of the related enzyme activities showed that the elicitation effect of A13 on LAB accumulation correlated with cinnamic acid 4-hydroxylase (C4H) activity in the phenylpropanoid pathway under field conditions. Our results confirmed that Alternaria sp. A13 not only contributes to the stimulation of S. miltiorrhiza root growth, but also boosts the secondary metabolism, thus demonstrating its application potential as a bio-fertiliser for S. miltiorrhiza cultivation, especially in areas outside of its native growth regions.

[Identification of water buffalo horn and its adulterants using COI barcode].

Bubali cornu (water buffalo horn) has been used as the substitute for Cornu rhinoceri asiatici (rhino horn) in clinical applications, and is the essential ingredient of Angong Niuhuang Wan. In recent years, there are a number of adulterants on the commercial herbal medicine markets. An efficient tool is required for species identification. In this study, 155 Bubali cornu samples have been taken from original animals and collected from commercial herbal medicine markets. 153 COI sequences have been successfully obtained from 155 samples through DNA extraction, PCR amplification, bidirectional sequencing and assembly. 93 COI sequences have been added to the DNA barcoding database of traditional Chinese animal medicine after validation using DNA barcoding GAP and tree-based methods. The species identification of the 62 commercial Bubali cornu medicines has been accomplished on the DNA barcoding system for identifying herbal medicine using the updated animal medicine database (www.tcmbarcode.cn). Except two samples failed to obtain COI sequences, 54.8% of the commercial Bubali cornu medicines were water buffalo horns and 29% were yak horns. Our results showed that yak horn was the major adulterant of Bubali cornu and the DNA barcoding method may accurately discriminate Bubali cornu and their adulterants. Therefore, we recommend that supervision on the herbal medicine markets should be strengthened with this new method to warren the effectiveness of herbal medicines.

[Effects of growth-promoting strain Mycena sp. M23 on photosynthesis of Aronia melanocarpa]. / ä¿ƒç”Ÿå°è‡å±žèŒæ ªM23å¯¹é»‘æžœè ºè‚‹èŠ±æ¥¸å ‰åˆä½œç”¨çš„å½±å“.

The agronomic traits, chlorophyll content, physiological indices of Aronia melanocarpa were compared in five treatments, namely negative control (CK), positive control (PCK), low dose of microbial inoculant (T1, 50 g per seedling), moderate dose of microbial inoculant (T2, 100 g per seedling), high dose of microbial inoculant (T3, 200 g per seedling) in field. The diurnal variation of net photosynthetic rate was measured by Li-6400 portable photosynthesis system. The diurnal variation of net photosynthetic rate (Pn) of A. melanocarpa showed a pattern of bi-modal curve with photosynthetic "noon break" phenomenon, which occurred at 1:00 pm. At that time, stomatal conductance (gs) and transpiration rate (Tr) of A. melanocarpa showed a dramatic decline, while intercellular CO2 concentration (Ci) significantly rose. It was a photosynthetic "noon break" phenomenon caused by non-stomatal limitation. Application of inoculant to A. melanocarpa successfully avoided the photosynthetic "noon break" phenomenon. Compared with average value of CK and PCK, Pn, gs, Tr, water use efficiency (WUE) and light utilization efficiency (LUE) of inoculation groups increased by 113%, 91%, 50%, 48% and 117% at 1:00 pm. Daily mean of Pn, gs, Tr and LUE of inoculation group was 1.5, 1.9, 1.4 and 1.5 times as that of average value of CK and PCK. The inductive effect of high dose of microbial inoculant treatment was the best among inoculation treatments, with the seedling height 1.2 times as that of the moderate and low inoculant groups. All growth indices, photosynthetic parameters and resistant physiological indices of high dose group were superior to other groups. Our results suggested that fungi M23 could improve the adaptability of A. melanocarpa to environmental stresses and promote its growth by increasing photosynthesis, with the inductive effect of high dose being the best.

Use of transcriptomic profiling to identify candidate genes involved in Polyporus umbellatus sclerotial formation affected by oxalic acid.

Polyporus umbellatus is a precious medicinal fungus. Oxalic acid was observed to affect sclerotial formation and sclerotia possessed more medicinal compounds than mycelia. In this study, the transcriptome of P. umbellatus was analysed after the fungus was exposed to various concentrations of oxalic acid. The differentially expressed genes (DEGs) encoding a series of oxidases were upregulated, and reductases were downregulated, in the low-oxalic-acid (Low OA) group compared to the control (No OA) group, while the opposite phenomenon was observed in the high-oxalic-acid (High OA) group. The detection of reactive oxygen species (ROS) in P. umbellatus mycelia was performed visually, and Ca2+ and H2O2 fluxes were measured using non-invasive micro-test technology (NMT). The sclerotial biomass in the Low OA group increased by 66%, however, no sclerotia formed in the High OA group. The ROS fluorescence intensity increased significantly in the Low OA group but decreased considerably in the High OA group. Ca2+ and H2O2 influx significantly increased in the Low OA group, while H2O2 exhibited efflux in the High OA group. A higher level of oxidative stress formed in the Low OA group. Different concentrations of oxalic acid were determined to affect P. umbellatus sclerotial formation in different ways.

[Molecular diversity of arbuscular mycorrhizal fungi in wild and cultured Gynostemma pentaphyllum roots in Xishuangbanna, Southwest China].

By using nested-PCR, DNA cloning, and sequencing techniques, this paper studied the diversity of the community structure of arbuscular mycorrhizal fungi (AMF) in wild and cultured Gynostemma pentaphyllum roots. A total of 551 clones containing 18S rDNA genes of AMF were obtained from the roots. After the analysis of the restriction fragment length polymorphism, 100 different RFLP types were obtained, which were further divided into 20 AMF phylotypes belonging to seven families. The comparison of the sequences of 20 AMF phylotypes with the GenBank database showed that there were 5 AMF phylotypes having high similarity to the sequences of reported AMF species Glomus viscosum, Claroideoglomus etunicatum, Racocetra tropicana, Acaulospora spinosa, and Acaulospora mellea, respectively. These sequences were then assessed for the similarities against the MaarjAM database, and 12 phylotypes showed high similarity to the corresponding molecular virtual taxa, of which, 7 phylotypes were not obtained by the morphological identification of soil asexual spores. Statistical analysis indicated that there were significant differences in the AMF community between wild and cultured G. pentaphyllum roots. The analysis of relative abundance data indicated that Glo-2, Amb-1, and Para-1 were the dominant phylotypes in wild G. pentaphyllum roots, while Glo-3, Glo-8, Glo-10, and Div-1 were the prevalent phylotypes in cultured ones. Claroideoglomeraceae and Ambisporaceae were only detected in wild G. pentaphyllum roots, and Diversisporaceae was only identified in cultured ones.