International Journal of Agriculture and Biology最新文献_第10页

Effect of Chemical Reclamation on the Physiological and Chemical Response of Rice Grown in Varying Salinity and Sodicity Conditions 化学改良对不同盐碱条件下水稻生理化学反应的影响

International Journal of Agriculture and Biology Pub Date : 2021-07-01 DOI: 10.17957/ijab/15.1813

A. Qadir

{"title":"Effect of Chemical Reclamation on the Physiological and Chemical Response of Rice Grown in Varying Salinity and Sodicity Conditions","authors":"A. Qadir","doi":"10.17957/ijab/15.1813","DOIUrl":"https://doi.org/10.17957/ijab/15.1813","url":null,"abstract":"Salinity and sodicity are the major abiotic constraints that prevail in arid and semi-arid regions. Proper management is required for productive use of this land. Reclamation of sodic and saline-sodic soils is highly site-specific that describes the diverse response of different soils to different amendments. These reclamation practices also alter the plant's physiological and ionic characteristics. This experiment aimed to better understand the physiological and ionic responses of rice crop at different salinity/sodicity levels. A lysimeter experiment was set forth with soil having ECe (dS m-1):SAR (mmol L-1)1/2 levels as 4:20, 8:40, 12:60 and 16:80 and all the levels were treated with organic (farm manure at 25 Mg ha-1) and inorganic (gypsum at 100% soil gypsum requirement (SGR) and sulphuric acid equivalent to 100% SGR) amendments keeping no ammendment as control. Results revealed that the maximum relative increase in physiological attributes (photosynthetic rate, transpiration rate, stomatal conductance and total chlorophyll contents), ionic contents (nitrogen, potassium and K:Na ratio) and growth of rice were recorded with sulphuric acid application followed by gypsum. On an average 25%, 31% and 45% increase in biological yield, plant height and paddy yield, respectively was observed with sulphuric acid application over control. It is concluded that sulphuric acid and gypsum both were the best amendments for reclamation of soil having a low level of salinity/sodicity whereas, at higher salinity/sodicity levels, only sulphuric acid seemed better for improved rice production. © 2021 Friends Science Publishers","PeriodicalId":13769,"journal":{"name":"International Journal of Agriculture and Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48617623","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Mechanisms of Antimicrobial Resistance in Pseudomonas aeruginosa and a Multi-Pronged Approach to Combat its Infection in Veterinary Science and Public Health: A Review 铜绿假单胞菌的耐药机制及其在兽医科学和公共卫生领域的多管齐下的防治方法综述

International Journal of Agriculture and Biology Pub Date : 2021-07-01 DOI: 10.17957/ijab/15.1801

B. Mustafa

{"title":"Mechanisms of Antimicrobial Resistance in Pseudomonas aeruginosa and a Multi-Pronged Approach to Combat its Infection in Veterinary Science and Public Health: A Review","authors":"B. Mustafa","doi":"10.17957/ijab/15.1801","DOIUrl":"https://doi.org/10.17957/ijab/15.1801","url":null,"abstract":"Pseudomonas aeruginosa is one of the most important nosocomial pathogens associated with a variety of medical and veterinary infections and therefore, it presents a major public health threat. Different classes of antibiotics are being used to treat its infections which are increasing selective pressure to multi-drug resistance development. Resistance to antibiotics in P. aeruginosa is due to many of the common and unique mechanisms which include: reducing membrane permeability, modification or inactivation of antibiotics, alteration of enzymes, modification of target sites and over-expression of efflux systems. Over or under expression of the genes of porin channels and components of efflux systems play a major role in the resistance mechanisms of P. aeruginosa. To overcome the problem of the emergence of antibiotic resistance, many new strategies are being employed to control infections caused by P. aeruginosa. These include the use of herbs/medicinal plants and phage therapy. With the advent of modern technology, the molecular mechanisms of these alternative therapies are being elucidated and may be used in future to treat P. aeruginosa infections in humans and veterinary clinics. This review thus highlights the mechanisms of antibiotic resistance of P. aeruginosa against the commonly used antimicrobials and also some alternative strategies to control P. aeruginosa infection. © 2021 Friends Science Publishers","PeriodicalId":13769,"journal":{"name":"International Journal of Agriculture and Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41305607","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Physicochemical Characterization and Brix in Jersey Cow Colostrum in Tropical Conditions 热带条件下泽西牛初乳的理化特性和糖度

International Journal of Agriculture and Biology Pub Date : 2021-07-01 DOI: 10.17957/ijab/15.1818

E. G. S. O. Silva

{"title":"Physicochemical Characterization and Brix in Jersey Cow Colostrum in Tropical Conditions","authors":"E. G. S. O. Silva","doi":"10.17957/ijab/15.1818","DOIUrl":"https://doi.org/10.17957/ijab/15.1818","url":null,"abstract":"The objective of this study was to evaluate the nutritional composition (fat, total protein, casein, defatted dry extract, total solids and vitamin A), refractometry and pH of Jersey cow colostrum and correlations between Brix degree and colostrum constituents. Colostrum samples were collected from Jersey cow in the fifth milking after calving. Samples were identified and refrigerated until analysis. Data were subjected to analysis of variance and a descriptive analysis, while differences between milk were compared by the Duncan’s test (P < 0.05) using the SAS version 9.0 software program. Pearson correlations were then performed between Brix grade and bovine colostrum constituents. The fat, total protein, casein, total solid and Brix percentage of the colostrum gradually decreased from the first to the fifth milking, while the lactose content increased. Positive correlations were observed between Brix values and protein, casein, total solids and defatted dry extract contents, while lactose was negatively correlated. The rapid reduction in Brix means and protein concentrations after delivery demonstrates the importance of administer colostrum in the shortest period after birth. © 2021 Friends Science Publishers","PeriodicalId":13769,"journal":{"name":"International Journal of Agriculture and Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41347470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Resistance of DB1 Transgenic Rice Line and others against Nilaparvata lugens, Brown Planthopper 转DB1基因水稻系等对褐飞虱的抗性

International Journal of Agriculture and Biology Pub Date : 2021-07-01 DOI: 10.17957/ijab/15.1816

N. Carsono, G. I. Prayoga, D. Dono, S. Sari, K. Toriyama

{"title":"Resistance of DB1 Transgenic Rice Line and others against Nilaparvata lugens, Brown Planthopper","authors":"N. Carsono, G. I. Prayoga, D. Dono, S. Sari, K. Toriyama","doi":"10.17957/ijab/15.1816","DOIUrl":"https://doi.org/10.17957/ijab/15.1816","url":null,"abstract":"Nilaparvata lugens (Stål), brown planthopper (BPH) is as a major pest of rice crop. Developing rice resistant to BPH is an economically and environmentally friendly approach. A transgenic rice line with DB1 (Dioscorea batatas tuber lectin 1) transgene has been engineered to overcome the problem. The objective of the experiment was to obtain the level of resistance of a DB1 rice line (DB1-inserted cv. Taichung 65) and some rice genotypes against two colonies of BPH. Resistance study was performed in BPH’s preference, honeydew excretion, crop damage, and population development. The resistant test was carried out using two biotypes BPH i.e., biotype 2 (Sukamandi) and biotype 3 (North Sumatera). The result showed that DB1 transgenic rice was moderately resistant to biotype 2, while to be susceptible when invested to biotype 3, indicating that the DB1 gene increases the resistance level, from susceptible to moderately resistant. All tested genotypes were chosen by biotype 2 for laying eggs, while for biotype 3 preferred five genotypes (DB1 transgenic line, PTB-33, Babawee, IR-64 dan IR-42). Genotype significantly differed on number of BPH and was considerably lower on PTB-33 than the others. Honeydew excretion of genotypes showed equal on biotype 2 and 3, except on biotype 3 of IR 42 (susceptible to BPH) which showing high amount of feces. PTB 33 had lower BPH population as compared to others, indicating high resistance to BPH of biotype 2 and 3 from Indonesia. © 2021 Friends Science Publishers","PeriodicalId":13769,"journal":{"name":"International Journal of Agriculture and Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44601360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evaluation of In Ovo Antiviral Activities of Medicinal Flowers against Newcastle Disease Virus and Avian Influenza Virus 药用花卉对新城疫病毒和禽流感病毒的卵内抗病毒活性评价

International Journal of Agriculture and Biology Pub Date : 2021-07-01 DOI: 10.17957/ijab/15.1823

Iqra Nazir

{"title":"Evaluation of In Ovo Antiviral Activities of Medicinal Flowers against Newcastle Disease Virus and Avian Influenza Virus","authors":"Iqra Nazir","doi":"10.17957/ijab/15.1823","DOIUrl":"https://doi.org/10.17957/ijab/15.1823","url":null,"abstract":"In Pakistan, the poultry industry is one of the rapidly growing industries. Due to lack of biosecurity measures, this is affected by some important infectious agents such as Avian Influenza virus (H9N2) and Newcastle disease virus (NDV) results in a huge economic loss. So, to control these losses discovery of new anti-viral drugs required to bring into line to fight against these infections. It is a general perception that the active components of medicinal plants have effective results against various infections like the influenza virus. The current therapeutic facilities need to be improved by investigating new antiviral drugs from natural resources to fight against viral infections. The present study was conducted on ethanolic extracts of seven different flowers to examine their antiviral activity against NDV and H9N2 in ovo using chicken embryonated egg inoculation. The spot agglutination and hemagglutination tests showed inhibitory effects of Rosa damascena Miller, Achillea millefolium, Woodfordia fruticosa Kurtz and Bombax ceiba L. against NDV as no agglutination observed. While the extracts of Taxacum officianale Weber, Hyssopus officianalis L. and Chrysanthemum cinerafolium (Trevis.) Vis. showed positive results for both spot agglutination and hemagglutination assay against NDV. However, both spot agglutination and hemagglutination assay showed inhibitory effect of all the flowers extracts against H9N2. The bioactive components such as alkaloids, ethers, terpenoids, etc. of each flower were analyzed through Gas chromatography mass spectrometry (GC-MS). The current results revealed that ethanolic extracts of these flowers possess strong antiviral activity because of their active ingredients. These ingredients should be isolated, commercialized and used for therapeutic purpose. © 2021 Friends Science Publishers","PeriodicalId":13769,"journal":{"name":"International Journal of Agriculture and Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48913783","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Heritability for Morphological Traits Determine Adaptability of Elite Cowpea Genotypes in different Environments 形态性状的遗传力决定了优良豇豆基因型对不同环境的适应性

International Journal of Agriculture and Biology Pub Date : 2021-07-01 DOI: 10.17957/ijab/15.1814

J. Asiwe

{"title":"Heritability for Morphological Traits Determine Adaptability of Elite Cowpea Genotypes in different Environments","authors":"J. Asiwe","doi":"10.17957/ijab/15.1814","DOIUrl":"https://doi.org/10.17957/ijab/15.1814","url":null,"abstract":"Lack of improved and high-yielding adapted varieties constitutes limitation to cowpea (Vigna unguiculata (L.) Walp) production in South Africa. Therefore, field trials were conducted in two locations (the University of Limpopo Experimental Farm, (Mankweng) and Towoomba Research Station, Bela-Bela) during 2015–16 and 2016–17, to assess yield components, genotype x environment interaction as well as the adaptability of elite cowpea genotypes. The experiment was laid out using a randomized complete block design in three replications. Data were collected on flowering, maturity and yield components. Results revealed that “genotype, and genotype × year and genotype × location interactions were significant for most of the traits evaluated”. „The days to 50% flowering‟ and „90% maturity‟ ranged between 53 and 60 days, and between 89 and 96 days, respectively. The „100-seed weight‟ varied from 15.8 g to 22.5 g. „Broad-sense heritability‟ varied from 0 to 93% for days to maturity and grain yield, respectively. „Grain yield‟ varied from 1465.7 to 2594.9 kg ha-1, and the best yielders were lines „L2‟, „L10‟, and „L7‟. The „PC1‟ and „PC2‟ explained 82.57% variation for maturity, 79.12% for the „pods per plant‟, 83.78% for „seeds per pod‟, 93.09% for „100-seed weight‟ and 95.84% for „grain yield‟. Towoomba was a more productive location compared to Sykerfuil. Lines „L2‟, „L10‟, and „L7‟ yielded very well in both locations and years. This implies that they are adapted and are recommended for registration and commercial release in the region. © 2021 Friends Science Publishers","PeriodicalId":13769,"journal":{"name":"International Journal of Agriculture and Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44096497","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Transient Expression of Chi42 Genes from Trichoderma asperellum in Nicotiana benthamiana by Agroinfiltration 木霉Chi42基因在烟草中的土壤渗透瞬时表达

International Journal of Agriculture and Biology Pub Date : 2021-07-01 DOI: 10.17957/ijab/15.1822

Nguyen-Quang-Duc Tien

引用次数: 7

Dietary Replacement with Food Waste and Black Soldier Fly Larvae Supplementation Improved Growth Performance, Nutrient Digestibility and Intestinal Microbial Population in Broilers 饲粮中添加食物垃圾和黑虻幼虫可提高肉仔鸡生长性能、营养物质消化率和肠道微生物群

International Journal of Agriculture and Biology Pub Date : 2021-06-01 DOI: 10.17957/ijab/15.1780

M. Al-qazzaz

{"title":"Dietary Replacement with Food Waste and Black Soldier Fly Larvae Supplementation Improved Growth Performance, Nutrient Digestibility and Intestinal Microbial Population in Broilers","authors":"M. Al-qazzaz","doi":"10.17957/ijab/15.1780","DOIUrl":"https://doi.org/10.17957/ijab/15.1780","url":null,"abstract":"This study was aimed to evaluate the effect of conventional ingredients replacement with alternative ingredients on growth performance, carcass quality, nutrient digestibility and intestinal microbial of broilers. One hundred twenty Cobb500 broiler chicks were randomly assigned to four diets. Corn, soybean meal and fish meal were replaced with rice waste, meat and bone waste and black soldier fly larvae (BSFL) at 0, 10, 30 and 50% to form four treatments. Body weight gain, feed conversion ratio and digestibility of crude protein and fat were improved in broilers fed the replacement diets. Feed intake was not affected by the treatments suggesting that the replacement diets were well accepted by the chicken. Escherichia coli was decreased in the cecum and Lactobacillus were increased in the intestines of broilers fed the replacement diets. The fiber and chitin contents in the replacement diets may alter intestinal bacterial fermentation leading to improved nutrient digestibility. However, abdominal fat percentage increased in broilers fed the replacement diets. In conclusion, conventional ingredients can be replaced with up to 50% rice waste, meat and bone waste and BSFL in the diets with promising effect on growth performance, nutrient digestibility and intestinal microbial populations. © 2021 Friends Science Publishers","PeriodicalId":13769,"journal":{"name":"International Journal of Agriculture and Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44975371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Potassium Uptake, Physiological and Molecular Responses in Different Winter Wheat Cultivars under Deficit Irrigation and Potassium Levels 亏缺灌溉和钾水平下不同冬小麦品种钾吸收、生理及分子响应

International Journal of Agriculture and Biology Pub Date : 2021-06-01 DOI: 10.17957/ijab/15.1749

Xinyang Bai

{"title":"Potassium Uptake, Physiological and Molecular Responses in Different Winter Wheat Cultivars under Deficit Irrigation and Potassium Levels","authors":"Xinyang Bai","doi":"10.17957/ijab/15.1749","DOIUrl":"https://doi.org/10.17957/ijab/15.1749","url":null,"abstract":"Improving potassium (K) use efficiency (KUE) is beneficial for the sustainable production of cereal crops. In this study, the effects of K input level on its uptake and agronomic trait of the winter wheat under deficit irrigation were investigated in K deprivation responses, using two cultivars contrasting (low-K tolerant cultivar Kenong 9204 and K deprivation sensitive one Jimai 120). Under sufficient-K treatment (K180, SK), the two cultivars showed similar K contents, and K accumulation, biomass, photosynthetic parameters in upper expanded leaves, including yield components. Under deficient-K (K60, DK) condition, both cultivars showed varied behaviors of the K-associated traits, physiological parameters, growth and agronomic traits; however, better response was observed in Kenong 9204 than Jimai 120. These results suggested the essential roles of low-K tolerant cultivars under the K-saving management together with deficit irrigation. Two genes of the potassium transporter (HAK) family, TaHAK3 and TaHAK5, showed expression of significantly upregulated upon K deprivation, with much more transcripts shown in the K-deprived Kenong 9204 plants than Jimai 120 ones. Transgene analysis on the HAK genes validated their positive roles in modulating the K accumulation and biomass production of plants under low-K condition. These results indicated that distinct HAK family genes are transcriptionally regulated underlying K deprivation signaling and contribute to plant K uptake and biomass production under low-K conditions. This study suggested the drastically genetic variation on K uptake and biomass production across winter wheat cultivars treated by K- and water-saving conditions, associated with transcription efficiency of the distinct HAK genes which modulate K uptake, growth and development of plants. © 2021 Friends Science Publishers","PeriodicalId":13769,"journal":{"name":"International Journal of Agriculture and Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45552054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Host Dependent and Geographical Structuring of Citrus Canker Bacteria at Peshawar, Pakistan 巴基斯坦白沙瓦柑桔溃疡病菌的寄主依赖性和地理结构

International Journal of Agriculture and Biology Pub Date : 2021-06-01 DOI: 10.17957/ijab/15.1797

Safi Ullah

{"title":"Host Dependent and Geographical Structuring of Citrus Canker Bacteria at Peshawar, Pakistan","authors":"Safi Ullah","doi":"10.17957/ijab/15.1797","DOIUrl":"https://doi.org/10.17957/ijab/15.1797","url":null,"abstract":"Citrus canker disease, caused by Xanthomonas axonopodis pv. Citri (Xac) induces huge losses to citrus, particularly in nurseries. This study assessed the level of genetic diversity and divergence in Xac population prevalent in district Peshawar on various host species, based on isolates collected from different fruit nurseries of Peshawar. Surveillance resulted in collection of 80 samples, out of which 50 bacterial samples were isolated. Genotyping of the isolates using RAPD markers amplified 35 scorable loci with an average of 8.7 loci per primers and level of polymorphism was 100%, i.e., almost all of the isolates genotyped had a different multilocus genotype. The loci GLA-031000 was recorded with the highest gene diversity (0.51) followed by GLB-05_1000 and GLA-03_1100 (0.49). The maximum diversity index (0.50) was recorded for loci GLA-031000, followed by GLB-051000 and GLA-03_1100 (0.48). A high diversity was observed across all locations, with the range of genotypic diversity from 0.778 (detected at Malakandair) to 0.955 (detected at Hayatabad and Tarnab). Divergence between samples collected from different locations was limited as revealed by the PCA, PCoA, phylogenetic tree and network analyses. Samples originated from various hosts also revealed a high diversity across host types with the minimum genotype diversity observed for Eureka Lemon (0.750) and the maximum for sweet lemon (0.966). The divergence for samples collected on various citrus host types was absent. The very small linkage disequilibrium (0.006–0.159) reflected on the potential recombination in the population, which must have direct implications to disease management and resistance exploitation. © 2021 Friends Science Publishers","PeriodicalId":13769,"journal":{"name":"International Journal of Agriculture and Biology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41386537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0