肉鸡大肠杆菌病模型及其病理指标的观测分析     

李东红  李金环 《中国家禽》2006,28(8):12-15

29日龄肉鸡腹腔接种0.5mL大肠杆菌肉汤悬浮液(O2标准菌株,2.1×109CFU/mL)建立了肉鸡大肠杆菌病模型,对其病理指标进行了观测与分析。结果表明:感染1h后肉鸡表现出发病症状,10h后发病率100%;试验期间死亡率55%,死亡时间在19～65h,扑杀感染鸡的脏器病变率为心包炎55%、肝周炎85%、气囊炎65%;感染后1～3d,肝脏大肠杆菌阳性率为100%,第7天为80%。感染后1～3d的体温极显著高于对照组(P<0.01)。感染后1～7d肉鸡的股动脉收缩压、舒张压和平均股动脉压极显著低于(P<0.01)对照组,分别平均下降了26.25%、27.72%、27.12%。感染后第7天肉鸡红细胞压积显著低于(P<0.05)对照组。  相似文献   

一株新分离雨生红球藻培养条件的优化          下载免费PDF全文

戴颖  穆亮亮  黄旭雄 《上海海洋大学学报》2023,32(1):68-78

为探究一株新分离雨生红球藻的适宜生长条件,以藻细胞密度为响应值,通过单因子试验方法,获得该株雨生红球藻生长的最佳光照强度、培养温度和接种密度分别为105 μmol/(m²·s)、21 ℃和 7.5×10⁴ cells/mL。然后采用响应曲面法(RSM)耦合Box-Behnken设计,建立了预测雨生红球藻细胞密度的二次多项式方程,培养光照强度、温度和接种密度及其二项式对雨生红球藻细胞培养密度有着显著影响。各因素影响强弱的顺序:接种密度>光照强度>培养温度。响应曲面法获得雨生红球藻的最佳培养条件为光照强度120 μmol/(m²·s),温度20 ℃,接种密度9.25×10⁴ cells/mL,在此组合条件下雨生红球藻细胞密度可达45.08×10⁴ cells/mL,比单因素实验得到的最高藻细胞密度高出6.9%。  相似文献   

Identification of resistance to anthracnose in leaves of grape resources and QTL localization of disease resistance genes北大核心CSCD     

Yu F.Zhang Y.Jiang J.Sun L.Liu C.Fan X. 《果树学报》2023,(11):2325-2339

【Objective】 Grape anthracnose is one of the main diseases of grape, which mainly infects the fruits, young leaves and new branches of grape, causing fruit rot, shedding, or water loss and shrinkage into stiff fruits. Breeding disease-resistant grape varieties is the most economical, effective, and environmentally friendly long-term control strategy for the prevention of the anthracnose disease. There have been a few studies on the identification of the resistance to anthracnose and the QTL localization of relative disease resistant genes so far. The study aimed to identify the resistance to the anthracnose disease of different grape germplasms and seek for new QTL locus for the resistance and provide germplasm materials and basis for the breeding and research on the disease resistance mechanism. 【Methods】 The indoor ex vivo leaf inoculation method was used to identify and evaluate the resistance to anthracnose in 60 strains of Chinese wild grapes, 122 accessions of V. vinifera and 76 accessions of V. vinifera-V. labrusca, and the hybrid offsprings of Manicure Finger (susceptible)×Ciputao0940 (resistant), and the QTL localization of grape anthracnose resistance was carried out using the genetic map constructed by SNP markers.【Results】 A total of 1 germplasm with high resistance, 43 germplasms with resistance and 75 germplasms with medium resistance were screened out, accounting for 0.39%, 16.67% and 29.07% of the total identified accessions, respectively. There were great differences in the resistance to anthracnose in different germplasm populations. 63.34% of the East Asian population 56.57% of the V. vinifera-V. labrusca population, and 31.15% of the Eurasian population had the resistance to anthracnose. In the identification of anthracnose resistance in Chinese wild grape germplasms, it was found that the resistance of different strains in the same population varied greatly, and the species with strong resistance on the whole included V. davidii, V. pseudoreticulata, V. amurensis, and V. piasezkii. The strong resistance of the strains include Shanputao &, Longyuwanfuye1 &, Duolieye-yingyu, Shanputao- shanyang1807, Mianmaoputao-chayu1955, and Ciputao0940. The resistance of the hybrid offsprings of Manicure Finger (susceptible)×Ciputao0940 (resistant) were distributed in five grades. According to the normality test and single-sample Kolmogorov-Smirnov test based on the resistance level distribution of the F1 population, it was found that the hybrid offsprings of Finger (susceptible) × Ciputao0940 (resistant) showed continuous variation in anthracnose resistance, which was a typical quantitative trait controlled by polygens, and the phenotypic distribution of disease resistance identification results showed a trend of partial normal distribution, which could be analyzed by QTL localization. In the positioning of QTL related to grape resistance to anthracnose, the interval or site of LOD≥3.0 was used as the threshold value for QTL, and when the above conditions were met, the site corresponding to the highest LOD value in the interval was considered to be one QTL of grape anti-anthracnose. In this experiment, a QTL interval associated with grape anthracnose resistance was detected on the 8th linkage group, and the locus with the highest LOD value in this interval was located at 140.682 cM, and the tightly linked label was Maker1675910, which could explain the 14.7% of the phenotypic variation. Based on the gene annotation results of the QTL locus interval, 15 resistance- related genes were screened out, and they were hypothesized to play a role in grape anthracnose resistance. 【Conclusion】 The resistance level of different grape germplasms to anthracnose was clarified, one QTL site against anthracnose was located and 15 resistant-related genes were screened. © 2023 Journal of Fruit Science. All rights reserved.  相似文献   

小麦网腥黑穗病温室内人工接种方法的探索     

秦丹丹  王俊  高海峰  李宁静  吴伟  刘太国  陈万权  高利 《植物保护》2021,47(1):165-168

小麦网腥黑穗病是由小麦网腥黑粉菌Tilletia caries引起,会导致小麦严重减产.为了获得小麦网腥黑穗病较高的发病率,本研究利用穗部接菌、土壤接菌、根部接菌3种方法进行温室内人工接种小麦.结果表明,利用穗部接菌及土壤接菌发病率分别为52.5％和10％,而根部接菌发病率仅有4％.利用穗部接菌可以获得更多的发病植株,...  相似文献   

微生物源的植物生长促进剂研究的新进展     

袁志林戴传超  杨启银 《中国土壤与肥料》2004,(6):41-46

本文综述了近几年国内外应用于生态农业的微生物源的植物生长促进剂的研究进展。涉及微生物制剂的种类、作用机理、剂型及其展望和发展趋势,为正确使用和进一步开发这类微生物制剂提供一定的理论依据。  相似文献   

食用菌袋栽液体接种机研发设计          下载免费PDF全文

陈长卿 《农业工程》2022,12(9)

目前国内食用菌袋栽液体接种机只有人工和半自动机型，生产效率低，接种量精度差，污染率高，不能达到食用菌袋栽规模工厂化生产要求。本文根据食用菌袋栽液体接种生产技术要求，对食用菌液体接种的自动运输、定位接种、检测等自动化连续作业进行研发设计，分析柔性接种定位难、接种量不均匀、污染率高等问题，提出规模化生产食用菌袋栽液体接种机研发设计方案，将极大提高接种质量和生产效率，促进我国食用菌行业的转型升级与可持续发展。  相似文献   

基因枪介导转化水稻花药愈伤获得抗白叶枯病转基因植株   总被引：9，自引：0，他引：9  

万丙良  张献龙 《华中农业大学学报》2001,20(1):1-6

以质粒pBI121作外源DNA，对基因枪介导转化水稻花药愈伤的有关参数进行了优化，优化值分别为射程9cm，枪膛氦气压力1100psi，真空度3600－3733Pa，轰击次数2次。轰击前后愈伤经0.4mol/L甘露醇处理可提高转化效率。在优化条件下将Xα21基因导入籼型光敏核不育水稻W9451S，获得了单倍体植株，经人工染色体加倍得倒二倍体转基因植株。白叶枯病菌接种鉴定结果表明其抗性有明显提高。  相似文献   

水稻稻曲病室内人工接种技术   总被引：8，自引：2，他引：6  

杨秀娟  王舒婷  阮宏椿  石妞妞  甘林  陈福如 《植物保护学报》2011,38(5):395-400

为提高稻曲病人工接种的发病效果和稳定性,在温棚条件下采用水稻孕穗期注射接种法分别研究了稻曲病菌不同接种体、培养时间、接种浓度和接种时期的接种效果。采用病菌马铃薯蔗糖液体培养基（potato sucrose broth,PSB）作为接种体,其穗发病率为100%,明显好于病菌米糠培养液（23.33%）。病菌在PSB中培养5～7天接种效果较好,随病菌培养天数的延长,接种效果明显下降。接种的分生孢子浓度越低水稻病穗率和病粒数也越低。在水稻品种两优培九孕穗中后期,采用含分生孢子浓度为4×106个/mL的病菌PSB培养液注射接种,穗发病率达100%,平均病粒数35.1粒,最高达87粒。研究表明,温棚条件下建立的稻曲病人工接种技术能获得稳定的发病效果,并可区别水稻品种间的抗性差异。  相似文献