EDS_（76）灭活油乳剂疫苗的乳化工艺研究

本研究是在研制成ＥＤＳ７６油乳灭活苗的基础上．用高压匀浆机代替原先使用的高速均装机来大批量生产疫苗．系统地研究了整个工艺流程中质量控制的各种因素，确定了水相和油相比例、乳化剂和稳定剂的ＨＬＢ值和乳化压力这３个技术参数．结果表明３３％的水相、复合乳化剂的ＨＬＢ值为７．１和在２０Ｐ压力下初次乳化。再在３０Ｐ压力下匀乳的工艺流程能获得稳定性好、粘度低、质量可靠的ＥＤＳ７６油乳剂灭活疫苗，适宜于生产实际使用．     

Detection of Huanglongbing (citrus greening) based on hyperspectral image analysis and PCR

Huanglongbing (HLB, citrus greening) is one of the most serious quarantine diseases of citrus worldwide. To monitor in real-time, recognize diseased trees, and efficiently prevent and control HLB disease in citrus, it is necessary to develop a rapid diagnostic method to detect HLB infected plants without symptoms. This study used Newhall navel orange plants as the research subject, and collected normal color leaf samples and chlorotic leaf samples from a healthy orchard and an HLB-infected orchard, respectively. First, hyperspectral data of the upper and lower leaf surfaces were obtained, and then the polymerase chain reaction (PCR) was used to detect the HLB bacterium in each leaf. The PCR test results showed that all samples from the healthy orchard were negative, and a portion of the samples from the infected orchard were positive. According to these results, the leaf samples from the orchards were divided into disease-free leaves and HLB-positive leaves, and the least squares support vector machine recognition model was established based on the leaf hyperspectral reflectance. The effect on the model of the spectra obtained from the upper and lower leaf surfaces was investigated and different pretreatment methods were compared and analyzed. It was observed that the HLB recognition rate values of the calibration and validation sets based on upper leaf surface spectra under 9-point smoothing pretreatment were 100% and 92.5%, respectively. The recognition rate values based on lower leaf surface spectra under the second-order derivative pretreatment were also 100% and 92.5%, respectively. Both upper and lower leaf surface spectra were available for recognition of HLB-infected leaves, and the HLB PCR-positive leaves could be distinguished from the healthy by the hyperspectral modeling analysis. The results of this study show that early and nondestructive detection of HLB-infected leaves without symptoms is possible, which provides a basis for the hyperspectral diagnosis of citrus with HLB.     

肇庆地区柑橘内生菌16S rDNA克隆与序列分析

[目的]研究柑橘黄龙病病原及其分化.[方法]采集肇庆周边各区县柑橘黄龙病的枝、叶共计8个黄龙病样品,利用黄龙病内生菌的细菌通用引物对其16S rDNA片段进行PCR扩增,将其扩增产物纯化、回收、克隆后,转化大肠杆菌,提取质粒,进行序列测定.[结果]所克隆的序列与众多的Uncultured bacterium都有极高的相似度,其序列在同源性检测中,与其相似度最高的是Uncultured bacteriumclone yf5-180,达到91.3％.[结论]表明肇庆周边黄龙病柑橘的枝、叶内生菌可以扩增出特异性16S rDNA片段,该序列属于一个新的细菌种属.     

柑橘黄龙病高光谱早期鉴别及病情分级

为实现柑橘黄龙病的早期、快速确诊,有效阻止病害蔓延,达到早期防治、保障柑橘生产的目的,该文研究基于高光谱成像的柑橘黄龙病早期无损检测及病情分级,并对多种预处理方法的建模结果进行探讨。试验获取370～1 000 nm健康、不同染病程度及缺锌共5类柑橘叶片的高光谱图像,用遥感图像处理平台(environment for visualizing images,ENVI)得到各类样本感兴趣区域的光谱反射率平均值。运用一阶微分、移动窗口拟和多项式平滑(savitzky-golay,SG)进行数据处理,结合偏最小二乘判别分析(partial least squares-discriminate analysis,PLS-DA)构建黄龙病的早期鉴别及病情分级模型。结果表明:建立的3个判别模型,验证集相关系数均不低于0.9548。其中,经SG平滑及一阶微分预处理所建立的模型分类效果最佳,总体预测准确率达96.4%,预测均方根误差0.1344。该研究为柑橘病害早期诊断和预警提供了新方法,也为黄龙病病害程度遥感监测提供了基础。     

乳化牛油的工艺研究

研究了不同乳化剂对牛油的乳化效果。根据乳液的稳定性来选择其最佳的亲水亲油平衡值(HLB)为10.53。在最佳HLB值下进行乳化剂的复配。当Tween80和单甘酯以3∶2的比例复配,且复配乳化剂的添加量为0.8%时,乳化牛油的效果最好。增稠剂可增强乳液的稳定效果,通过L9(34)正交试验确定的最佳增稠剂配比为黄原胶0.1%,瓜尔豆胶0.25%和卡拉胶0.1%,由此得到最稳定的乳液,其稳定系数为0.963。     

黄龙病对柑橘产业的经济损失评估： 基于投入—产出法的研究

黄龙病是一种传播快、危害大,迄今为止最具毁灭性的柑橘检疫性病虫害,其对全球柑橘产业的发展造成了巨大的影响,致使果农损失惨重。为此迫切需要量化研究黄龙病对柑橘产业造成的经济损失,从而为有效防控柑橘黄龙病、保护果农收益提供理论依据和决策参考。首先基于微观调研数据,测算黄龙病爆发导致赣南三县的直接经济损失;其次,采用投入产出法评估其间接经济损失。研究发现,黄龙病爆发造成赣南三县2016年的直接经济损失为44.92亿元,占当年GDP的15.4%,由于关联效应造成江西省的间接经济损失为42.91亿元,占当年GDP的0.23%,并且,黄龙病爆发对当地食品工业和服务业发展也带来了次生影响。     

响应黄龙病侵染的柑橘乙醇脱氢酶基因CsADH1的克隆与表达分析

对前期在感染黄龙病的‘晚锦橙’中发现的明显差异表达的柑橘乙醇脱氢酶（CsADH1）基因进行克隆测序分析,结果表明,CsADH1 的 CDS 序列长为 1 143 bp,编码 380 个氨基酸。蛋白质结构预测显示,CsADH1 含有乙醇脱氢酶 GroES（ADH_N）和 ADH_zinc_N 保守结构域。进化树分析显示,CsADH1 蛋白与拟南芥、蓖麻和中国莲的 ADH 蛋白亲缘关系最近。亚细胞定位结果显示,CsADH1 蛋白定位在细胞质中。以感病‘晚锦橙’的根和叶脉为材料,qPCR 分析显示 CsADH1 在感病根和叶脉中均上调表达,且根中的表达水平是叶脉中的 10 倍。离子胁迫试验和外源植物生长调节剂诱导试验表明,Zn、水杨酸（SA）、生长素（IAA）和脱落酸（ABA）均显著诱导 CsADH1 上调表达,并且根中的表达水平明显高于叶中。本结果表明,CsADH1 可能在柑橘根响应黄龙病菌侵染中起着重要作用。     

鸡肉、鸡蛋中4种酰胺醇类药物残留的液相色谱-三重四级杆串联质谱(UPLC-MS/MS)分析方法建立

建立了鸡肉、鸡蛋中4种酰胺醇类药物(氯霉素CAP、氟苯尼考FF、甲砜霉素TAP、氟苯尼考胺FFA)残留的超高效液相色谱-三重四级杆串联质谱(UPLC-MS/MS)快速分析方法。样品用80%的乙腈震荡提取,经过PRiME HLB固相萃取柱直接净化,在40℃下氮吹浓缩,最后用10%乙腈复溶。以0.01%甲酸水-0.01%甲酸乙腈溶液作为流动相进行梯度洗脱,采用多反应监测(MRM)模式进行测定,内标法定量。4种酰胺醇类药物在0.5~20 ng/mL的浓度范围内呈现良好的线性关系,R₂^在0.9982~ 0.9988范围内。添加量为0.5、1、5μg/kg时,鸡肉中4种酰胺醇类药物回收率为89.6%~104.2%,鸡蛋中4种酰胺醇类药物回收率为85.9%~105.5%。通过回收率和精密度试验得出该方法具有较好的准确度和重复性。通过试验得出4种酰胺醇类药物检出限为0.05~0.1 μg/kg,定量限为0.2~0.5 μg/kg,本法操作简便、灵敏,准确,适合大批量鸡肉、鸡蛋样品中4种酰胺醇类药物的检测。