The endophytic microbiota of hyperaccumulators is capable of tolerating high concentration of heavy metals, and its composition and diversity markedly vary with host plant species, soil and pollutant types, etc. Hyperaccumulator-associated endophytic microbiota has been reported to promote host plant growth by producing phytohormones, inhibiting ethylene production, increasing macro and micro nutrients and enhancing plant’s resistance to abiotic stress. On the one hand, endophytic microbiota can increase solubility and bioavailability of heavy metals by releasing of protons, carboxylic acid anions, bacterial siderophores and other chelators. On the other hand, the promotion of root growth and the formation of symbiosis mycorrhizae can increase the uptake of heavy metals by root. In addition, other processes such as redox, biosorption and bioaccumulation mediated by endophytic microbiota can also influence the uptake of heavy metals. In terms of application, endogenous microorganism of hyperaccumulator has good application prospects in strengthening phytoremediation, improving crop yield and biofortification of trace elements. In this paper, we reviewed the community composition and succession rule of endophytic microorganism in hyperaccumulator, as well as the mechanism of promoting plant growth, heavy metal activation and uptake, and its application in agricultural production. Based on that, the future research emphasis is put forward.

Phytochelatin (PC), which is produced under catalyzation of phytochelatin synthase (PCS), plays a key role in phytoremediation as its ability of conjugating heavy metal ion in plants. Intensive research on phytochelatin synthase is of great significance to understand the mechanism of heavy metal resistance in plants, as well as inspires on strategies for creating engineering plants to ameliorate soil contaminated by heavy metal. This review was based on five aspects including bifunctional enzyme property, gene expression and enzymology feature, species distribution and phylogeny, catalytic active center, and activating mode. PCS mainly catalyzes the process of phytochelatin synthesis, as well as acts as peptidase. The gene expression of PCS is constitutive, whereas it can be regulated by heavy metal ion like Cd2+ in a few species, and PCS is activated by some metal ions in which Cd2+ is the most effective. It is widely distributed and can be found in organism kingdom such as yeast and nematode besides plants where PCS family members have closer genetic relationship than in other species, which infer its roles in plant’s adaption to environment. The catalytic center of PCS is located at N-terminal, and the three amino acid residues corresponding to Cys70, His183 and Asp201 in cyanobacterium absolutely conserved in all species. The heavy metal activation of PCS is believed to be related to cysteine, including two hypotheses of direct contact activation of heavy metals and formation of indirect intermediates. At the last part of this review, further discussions and prospects are given on multiple functions, gene expression, activating mechanism of PCS, as well as application regarding to the genes, aiming to provide some insights and references for further study.

Tea polyphenols (TP) are the main active compounds in tea leaves. It is found that TP could inhibit cancer cell growth and induce cell apoptosis via modulating cell cycle, gene expression, signal transduction and transcription factor, etc. However, due to the low bioavailability of TP, it is hard for TP to work on cancer cells directly, which leading to the anti-tumor mechanism effect of TP is still unclear. As known, tumor immune escape is found to play a key role in tumor genesis and growth; immunosuppressive cells, such as myeloid-derived suppressor cells (MDSCs), are able to regulate anti-tumor immune response negatively, and mainly contribute to tumor immune escape. Recently, TP have been found to relieve immune escape and suppress spontaneous neuroblastoma cells through MDSCs, which provide a new sight into understanding the anti-tumor effect of TP. In this paper, the recent researches on the effects of tea polyphenols on immunosuppressive cells were reviewed in order to provide a reference for studying the anti-tumor mechanisms of tea polyphenols.

Oxidative stress has a negative impact on production performance, reproductive performance and disease resistance of dairy cows. It is particularly serious for high-producing dairy cows. The occurance of oxidative stress is closely related to the physiological stage, nutritional status and environmental temperature of dairy cows. At present, the common practice to prevent and relieve oxidative stress is to add vitamins, trace elements and plant extracts to the diets for cows. This review summarized the causes and harm effects of oxidative stress on dairy cows, as well as the antioxidant measures and their mechanisms, aiming to provide theoretical basis for antioxidant mechanism research and novel antioxidant exploitation in dariy cows.

In valley area of Tibet, seeds of common vetch (Vicia sativa L.) and oat (Avena sativa L.) were sowed at different ratios in mixtures and intercropping. The forage yield and nutritional quality of common vetch and oat were analyzed and compared, and the optimal sowing ratio of them which was suitable for the local conditions was selected. The results were showed as follows: 1) Compared with monoculture, mixture and intercropping increased the yields, and significantly increased the height of common vetch, but had no significant effect on the oat. 2) In all mixtures and intercropping groups, the crude protein (CP) content was increased with the increasing of seeding proportion of common vetch, and higher than that of monocultured oat. Among them, the monocultured common vetch had the highest CP content (21.9%), while the CP concent of monocultured oat was the lowest (5.5%). 3) Mixture and intercropping both increased the contents of neutral detergent fiber (NDF) and acid detergent fiber (ADF) in common vetch and oat, which increased by 27.3%-43.5% and 2.4%-17.6%, respectively. Moreover, the NDF content was increased as the seeding proportion of common vetch increasing, which was similar to the change of CP content; while the change trend of ADF was on the contrary. Based on the above results and the analysis of fuzzy mathematics membership function, it is indicated that the mixture of common vetch and oat performs more advantages on the forage yield and quality than intercropping as well as monoculture, and the optimal mixture ratio is common vetch 60% and oat 40%, which is suitable for application in valley aera of Tibet.

To reveal the mechanism of paclobutrazol (PP333) on drought resistance of Phyllostachys edulis seedlings, we set the PP333 concentrations with 0 and 40 mg/L and the relative water contents with 30% (drought stress) and 70% (normal water supply), and a total of four treatments in pot experiments. Membrane lipid peroxidases and the activities of antioxidant enzymes and contents of osmotic adjustment substances were determined at the 7th, 14th and 21st days under the drought stress, and the determination of height increment of seedlings, total biomass and leaf relative water content were conducted at the 21st day under the drought stress. The results showed that compared with the normal water supply, drought stress significantly reduced the height increment, total biomass, leaf relative water content, and the activities of catalase (CAT) and peroxidase (POD), but significantly increased the root shoot ratio, malondialdehyde (MDA) content, proline (Pro) content and superoxide dismutase (SOD) activity of P. edulis seedlings. Under the drought stress, the application of PP333 significantly reduced the seedling height increment to the lowest value of 1.50 cm, while the root shoot ratio reached the maximum value of 1.35. The application of PP333 could significantly reduced MDA content and improved the leaf relative water content, proline content, and the activities of SOD, POD and CAT. Under the normal water supply condition, the effect of PP333 was similar to that under the drought stress, while its efficacy was poor than that of the latter. In conclusion, the application of PP333 can increase the relative water content, root shoot ratio, osmotic adjustment substance (Pro) content and antioxidant enzyme activities, and decrease the MDA content to improve the drought resistance of P. eduli seedlings.

The study was carried out based on a long-term site field experiment that started from 2009 to 2014, with the same fertilizer application with P₂O₅ 75 kg/hm², K₂O 105 kg/hm². The nitrogen fertilizer was applied with five different amounts (0, 90, 180, 270 and 390 kg/hm², marked as N₀, N₁, N₂, N₃, N₄), which was added to the maize in a ratio of 3∶3∶4 referring to base fertilizer∶stem elongation∶head sprouting. The results showed: 1) The biomass, grain yield of maize increased first and then decreased with the increasing amount of nitrogen fertilizer application. The grain yield of N₁, N₂, N₃, and N₄ treatment was higher 83.8%, 116.1%, 109.7% and 69.4% than that of N₀, respectively. Moreover, the N₂ treatment obtained the highest biomass which was 197.5%, 23.0%, 9.4% and 9.6% more than that of N₀, N₁, N₃ and N₄, respectively. 2) The partial factor productivity of applied nitrogen (PFP-N) and the agronomic utilization efficiency of the maize presented a decreasing trend with the increasing of nitrogen application. The harvest index of nitrogen in different treatments differed from each other in which N₃ (66.7%)＞N₂ (63.8%)＞N₁ (61.1%)＞N₀ (57.7%)＞N₄ (51.9%). The utilization rate of N fertilizer in the current season showed reduction with the increment of N fertilizer application in which the highest rate was 85.9% from N₁ while the lowest was 29.9% in N₄ treatment. 3) The assimilation of N, P and K in the same organ of maize showed a huge difference. For example, the grains, leaves and corn cob preferred to assimilate more N than P and K, and the stem and leaf sheath absorbed more K than N and P, whilst the root absorbed more K than N and P. 4) The ammonium and nitrate nitrogen of soil in the harvest stage of maize increased with the increase of nitrogen fertilizer application, but the ammonium nitrogen of soil was still at a low level, which was lower than the nitrate nitrogen in each treatment. In summary, the optimum amount of nitrogen fertilizer for a long-term agricultural cultivation of maize is 180 kg/hm², which could keep the fertility of soil and also protect the environment.

By field investigation of introduced color-leaf plants, we chose 43 main kinds of color-leaf plants in Northern Anhui as the research objects, which including Acer saccharum, Photinia fraseri, Prunus persica ‘Atropurpurea’, Aucuba japonica var. variegata, Ligustrum vicaryi, etc. In the premise of sufficiently considering the biological characteristics, ecological adaptability and ornamental feature, a comprehensive evaluation model of color-leaf plants was established by using the analytic hierarchy process to evaluate the 43 kinds of color-leaf plants in Northern Anhui with specific evaluation indexes and scoring criteria. As indicated by the weight value of standard layer in the comprehensive evaluation model, color duration, leaf color and cold resistance are important factors to evaluate introduced color-leaf plants. The plants were divided into four grades according to the scores, among which, the 13 species had the highest application value, such as Acer negundo ‘Aurea’, etc; the 16 species had the higher application value, such as Aucuba japonica var. variegata, etc; the 11 species had common application value, such as Acer saccharum, etc; the rest 3 species had lower application value, such as Pyracantha fortuneana‘Harlequin’, etc. This study provides a reference for rational development and application of these introduced color-leaf plants in Northern Anhui Province.

Cytoplasmic male sterility (CMS) 09-05A is a new CMS line in spring stem mustard that is transferred from oxa A CMS. In this study, morphological and cytological observation of anther and pollen grain of 09-05A CMS was carried out by scanning electron microscopy and transmission electron microscope. It was revealed that the microspore abortion were initiated at the uninucleate stage. The cell nucleus and other cellular components of microspores were degraded to form collapsed and abortive pollen grains eventually during the pollen development. This study clarified the abortive stage and cytological characteristics, which may help to uncover the developmental mechanism of CMS 09-05A and provide a theoretical basis for the heterosis utilization of CMS in stem mustard (Brassica juncea var. tumida Tsen et Lee).

Taken Miichthys miiuy as an experimental material, we investigated the effects of tea polyphenols-chitosan complex solution on changes of main quality indicators (biogenic amine content, volatile base nitrogen content, total bacterial counts) of Miichthys miiuy under 25 ℃ and 4 ℃ storage condition. Tea polyphenols and chitosan were formulated into a complex solution by an orthogonal experiment, and the biogenic amine content was used as an evaluation index to screen out the optimum proportion for inhibiting biogenic amine production. After treatment of the optimum proportion of tea polyphenols-chitosan complex solution, the contents of biogenic amines and volatile base nitrogen, and the total bacterial counts of Miichthys miiuy stored at 25 ℃ and 4 ℃ were determined and analyzed. The results showed that the complex solution of 3 g/L tea polyphenols and 10 g/L chitosan was the optimal proportion, which significantly reduced the content of biogenic amines in Miichthys miiuy under the storage of 25 ℃ for 24 h and 4 ℃ for 12 d, respectively. Moreover, the contents of biogenic amines and volatile base nitrogen, and total colonies in Miichthys miiuy stored at 25 ℃ and 4 ℃ were lower than those of the untreated control group, and their shelf life could be extended to 30-36 h and 12-15 d, respectively.

The paper examined the effects of soil salinity and rhizospheric factors (i.e. the root, arbuscular mycorrhizal fungal (AMF) hyphae, and soil solution) on the interspecific interaction of plant seedlings. The experiments were conducted by using Tamarix chinensis Lour. as neighbor plant and Medicago sativa L. as target plant. Five rhizospheric factor treatments were without rhizospheric interaction, with total rhizospheric interaction, with AMF hyphae interaction and soil solution interaction and with only soil solution. Three salinity levels were 0.05%, 0.2% and 0.5% as stress gradient for plants. A relative interaction index (RII) was used to indicate whether the effects of neighbor seedling on target seedling were positive or negative (facilitative or competitive), or neutral (without interaction). The results showed that: 1) The AMF colonization rate in the target plant seedling of M. sativa was enhanced by neighbor T. chinensis seedlings under the high soil salinity level (0.5%). Biomass of T. chinensis (neighbor species) seedling did not decrease, but biomass of M. sativa (target species) seedling decrease significantly as soil salinity increased. 2) The RII of total rhizosphere interaction between seedlings of T. chinensis and M. sativa were 0.240 0 (positive), 0.040 0 (neutral) and －0.110 0 (neutral) under 0.05%, 0.2% and 0.5% salinity levels respectively, where the total rhizosphere effect shifted from positive to neutral as the soil salinity level increased. 3) The root effects on the RII were 0.330 3 (positive), 0.294 4 (positive), 0.057 2 (neutral) under 0.05%, 0.2%, and 0.5% of salt levels, indicating the positive effect decreased with the increase of salt levels. 4) The AMF hyphae effects on RII were －0.040 0 (neutral), －0.150 0 (negative), and －0.020 0 (neutral) under 0.05 %, 0.2% and 0.5% salt levels. 5) The soil solution effects on RII were 0.006 0, 0.006 0, －0.034 0 (neutral all) under the three salinity levels. In conclusion, the rhizosphere factors (the root, AMF hyphae, and soil solution) differ in their effects on plant-plant interactions, and these effects are affected by soil salinity. The root facilitates plant-plant interactions under the low soil salinity level, but this facilitation declines as the soil salinity level increases. AMF hyphae enhance the competition under the low soil salinity level;
however, this negative effect weakens as the soil salinity level increases. Neighbor soil solutions do not affect the nature and intensity of plant-plant interactions.

We carried out pathogen detection of 282 clinical samples collected from Zhejiang Province and its 24 surrounding areas during April 2013 to April 2017. Among them, 16 positive samples were selected for S gene cloning and sequencing. The results showed that the detection rate of porcine epidemic diarrhea virus (PEDV), porcine group A rotavirus (GARV), porcine deltacoronavirus (PDCoV) and porcine transmissible gastroenteritis virus (TGEV) was 64.89% (183/282), 0.35% (1/282), 4.25% (12/282) and 0% (0/282), respectively. During November 1st to April 1st of the next year, the detection rate of PEDV was 74%, which was 26% in the remaining time. PEDV can be divided into three groups by molecular evolution analysis based on spike (S) protein. All of the 16 positive samples were located in the group Ⅲ. Compared with vaccine strains CV777, SM98, and DR13, the PEDV positive samples shared S gene homology of 93.6%-95.2% in nucleotide identities and 92.4%-94.9% in amino acid identities. Compared with vaccine strain CV777, three additional N- glycosylation sites were formed and one N-glycosylation site was disrupted in the 16 isolated strains. In sum, currently, the main pathogens of piglet diarrhea were PEDV mutants. Prevention and control of porcine epidemic diarrhea should be paid attention to seasonal fluctuations and accelerate the development of epidemic strain vaccine.

To investigate the attenuating effect of taurine on oxidative damage induced by cadmium in testicular cells of embryonic chicken, embryonic testis cells from 18-day-old chickens were cultured in serum-free McCoy’s 5A medium as a model. By cell morphological observation, methyl thiazolyl tetrazolium (MTT) assay, biochemical index determination, 5-bromo-2-deoxyuridine (BrdU) incorporation, TdT-mediated dUTP nick end labeling (TUNEL) method, Western blotting (WB), fluorescence quantitative polymerase chain reaction (PCR) and immunofluorescence staining methods, cell proliferation, mitochondria signal, endoplasmic reticulum stress signal, nuclear factor-erythroid 2 related factor-2 (Nrf2) and hemeoxygenase-1 (HO-1) signaling were studied to reveal its action mechanisms. The results showed that, cadmium resulted in testicular germ cells of embryonic chicken more vulnerable to oxidative damage. Compared with the control group, the testicular germ cells treated with cadmium presented condensed nuclei, vacuolated cytoplasm and marginalized chromatin. After cadmium treatment, the number of germ cells and cell vitality of embryonic chicken testes decreased significantly. Hydrogen peroxide, malondialdehyde and reactive oxygen species increased significantly, but superoxide dismutase activity decreased significantly. Cell proliferative ability decreased significantly, while apoptotic cells increased significantly. The expression of endoplasmic reticulum stress related genes (GRP78, XBP- 1), and apoptosis-related genes (Cyt C, p53 and caspase 9) mRNA increased significantly. Meanwhile, the expression of Nrf2 and p-Nrf2 proteins and HO-1 mRNA increased significantly (P＜0.05). However, simultaneous supplementation with taurine significantly restored the oxidative damage induced by cadmium. The germ cell numbers and cell vitality increased apparently; the antioxidant levels and endoplasmic reticulum stress witnessed a return to normal levels. In addition, the number of cell proliferation increased but apoptotic cells experienced a decline, and Nrf2 expression was restored. Consequently, taurine can relieve reproductive toxicity of cadmium, not only by restoring the balance of oxidation and anti-oxidation, but also by promoting testicular cell proliferation and inhibiting apoptosis.

In order to screen out the individuals of myostatin (MSTN) gene mutation, and breed fine poultry breeds with higher meat yield through a number of generations in Jingning chicken population, the fifth generation of Jingning chicken was selected as experimental objects to construct DNA pools, and the MSTN gene encoding sequence of Jingning chicken was obtained through segment amplification method, and the single nucleotide polymorphism (SNP) screening and bioinformatics analysis were carried out. The results showed that the coding sequence (CDS) region of MSTN gene in Jingning chicken was 1 128 bp long, encoding 375 amino acids, and the protein encoded by MSTN gene was hydrophilic protein. Four SNPs were found in CDS region including exon1-c.60G＞A, exon1-c.195C＞G, exon1-c.234G＞A, exon3-c.966G＞T, which were all synonymous mutations. The change of mRNA, secondary structure and free energy after nucleotide mutation led to the change of its structural stability. The main components of the protein secondary structure and tertiary structure were random coil, and the extended strand, α -helix and β -turn were scattered throughout the protein structure. The above result indicates that the MSTN gene of Jingning chicken has high mutagenicity, which provides molecular basis for marker-assisted selection of growth traits in Jingning chicken.

In order to investigate the effect of Cordyceps sinensis mycelium on the immune function of Rex Rabl rabbit, feeding experiments were carried out on mother Rex Rabl rabbits and their weaning young rabbits with the additive of zymotic fluid of C. sinensis mycelium. In the experiment of mother rabbit, 80 pregnant Rex Rabl rabbits of similar body mass were randomly divided into two groups. Between them, the control group was fed with basal diet and the treatment group with improved diet (added 2% zymotic fluid of C. sinensis mycelium based on basal diet). In the experiment of weaned young rabbit, the treatment groupⅠwith 10 offsprings from the previous treatment group and the treatment group Ⅱ with 10 offsprings from the previous control group were both fed with improved diets, and the control group with 10 offsprings from the previous control group was fed with basal diet. The results of mother rabbit experiment showed that the survival rate of young rabbits of the treatment group was significantly higher than that of the control group by 28 percentage points (P＜0.01), and the overall death rate of the treatment group was significantly lower than that of the control group by 33.5 percentage points (P＜0.05). Moreover, the IgAcontent of lactating female rabbits in the treatment group was significantly higher than that in the control group (P＜0.01). The results of weaning young rabbit experiment indicated that the rabbit appendix index of the treatment groupⅠwas significantly higher than that of the control group, and the positive rates of T lymphocytes in the treatment groupⅠand Ⅱ were significantly enhanced in comparison to that in the control group (P＜0.01). In conclusion, feeding the mother rabbits in pregnancy
and lactation with improved diet containing zymotic fluid of C. sinensis mycelium is helpful to reduce the infant rabbit mortality and increase the IgA content of mother rabbit. Feeding the weaning rabbits with improved diet is also beneficial to enhance immune organ mass and positive rate of T lymphocyte of young rabbits. This study indicates that the immune function and disease-resistant ability of Rex Rabl rabbits can be enhanced by adding zymotic fluid of C. sinensis mycelium in basal diet.

A method for the detection of pesticide residues on broccoli was proposed based on hyperspectral image technology. Four groups of broccoli samples were used as experimental samples, which contained imidacloprid, abamectin and propineb as the first third groups respectively, and the last group was sprayed with water. A total of 180 broccoli samples were scanned by hyperspectral image system in the range of 383.70-1 032.70 nm. The average spectral information of region of interest (ROI) was extracted. Then, piecewise multiplicative scatter correction (PMSC) was adopted to eliminate light scattering of the average spectral information. To increase efficiency of the model and reduce the redundancy of the hyperspectral image, using the principal component analysis (PCA) algorithm and successive projection algorithm (SPA) for feature extraction. Mahalanobis distance (MD), least square support vector machine (LSSVM), artificial neural networks (ANN) and extreme learning machine (ELM) models were created to predict the pesticide residues from full spectra and characteristic wavelengths. The results showed that the optimal model is the SPA-ELM model, and the accuracy of training set is 98.33%, and the correct rate of test set is 96.67%, suggesting that it is feasible to use the principal component analysis algorithm and the artificial neural network algorithm to identify the pesticide residues on the surface of broccoli. In sum, this study develops a new method for rapid and nondestructive detection of pesticide residues on the surface of broccoli.