本文概述了2013—2016年我国进口植物种子的基本情况,显示进口量在2014年达到峰值,随后2年略有下降,但总体维持在高位.在对疫情截获进行分析后发现,尽管近两年植物种子进口量略有减少,但截获的有害生物始终呈上升趋势,全年截获种次在4年间增加了43％;尤其是检疫性有害生物截获种次数大幅度提升,4年内增加了90％.为提升检疫工作效率,加强风险拦截力度,应从产品源头、分类管理、检疫审批和口岸检测等多个方面着手,打造全方位的植物种子检疫监管模式.

Kreuze et al.(2009)发现病毒特异的小RNA(small RNA,sRNA)为多拷贝的重叠序列,推测可通过深度测序技术获得病毒的大量sRNA序列,经拼接和比对分析后能高效鉴定病毒种类.目前,利用sRNA深度测序技术已在作物和昆虫上发现多种病毒(Liu et al.,2011;He et al.,2015).2013年本课题组在葡萄病害调查过程中发现,伊犁州部分地区的葡萄在种植4～5年后,叶片黄化、变小,整个植株矮化,座果率低,严重时甚至整株枯死;有的葡萄园发病植株达80％,造成极大的经济损失.本试验采集黄化、矮缩的葡萄病叶,利用sRNA深度测序技术进行检测,以期为快速准确鉴定葡萄上携带病毒提供技术支持.

A Phytophthora isolate 9099 from the diseased Californian Citrus grandis fruit was identified in this study.The observation of morphological characteristics of the isolate,pathogenicity assay,PCR detection based on ITS sequence and sequence analysis were conducted.The colony of the isolate is flat,velvet-like on V8 medium,and white-colored with irregular margin on PDA medium.The sporangia are ovate or elliptic in shape,and the size is 28.4-46.8 μm long × 16.3-23.8 μm wide (average 37.5μm × 19.4 μm),with a length/width ratio of 1.7-2.2 ∶ 1.The isolate is homothallic,and its oospores are yellow-orange,plerotic and 26.3-39.3(average 32.7) μm in diameter with a cell wall thickness of 1-3 μm.The expected bands of 407 bp and 616 bp were amplified from the isolate by P.hibernalis specific primer pairs PHIB1/PHIB2 and 751F/752R,respectively.ITS sequence of the isolate showed 99.89％-100％ identity with P.hibernalis ITS sequences (Accession No.EU686391,GU258886 and AY369370) deposited in GenBank.Phylogenetic tree based on the ITS sequences showed the isolate 9099 was clustered closely with P.hibernalis.Typical symptom of brown rot was observed on the grapefruit 7 days after wound inoculation with isolate 9099.Taken together,the isolate 9099 was identified as P.hibernalis.

A kind of teliospores in wheat(Triticum aestivum) samples that imported from USA manifests the morphological characteristics with Tilletia walkeri.The sequences of rDNA-ITS and mitochondrion gene were amplified separately by PCR and sequenced for identification of this teliospore.The sequence analysis showed that the ITS and mitochondrion DNA sequence of the teliospore shared high identity with T.walkeri in GenBank,Based on the morphological characteristics and the sequence analysis of PCR products,the teliospores from wheat samples were identified as T.walkeri.

A bacterial strain 5093-1 was isolated from the hyacinth bulbs introduced from the Netherlands which had a typical soft rot symptom.Its colonial morphology was observed,and its pathogenicity and hypersensitive reaction were tested.Also the 16S sequence analysis and Biolog testing were made.The results showed that the artificial inoculation with the isolate could cause hyacinth seedlings,potato tubers and butterfly orchids to produce rot and also could lead tobaccos to hypersensitive necrosis.The sequence similarity between the isolate and Dickeya chrysanthemi was 99.6%,and the isolate was identified as Dickeya chrysanthemi by Biolog testing.It was concluded from the above results that the strain 5093-1 is Dickeya chrysanthemi.

蝴蝶兰种苗携带介质出口一直以来是植物检验检疫的难点,以美国、加拿大为代表的北美洲,禁止我国携带介质种苗进口.近几年,在出入境检验检疫系统和企业的共同努力下,携带介质植物出口的检疫工作取得了突破,部分企业获得了进口准入.

植物繁殖材料尤其是活体植株本身携带疫情的风险高,随国际会展带来的疫情传入隐患大.本文简述了在2010年上海世博会期间,进境植物繁殖材料的检验检疫工作.通过总结,对如何完善国际会展进境植物繁殖材料的检验检疫工作提出相关建议.

The immuno-capture polymerase chain reaction(IC-PCR) technique by combining immuno-capture of the bacteria and polymerase chain reaction(PCR) amplification of its amsG gene was developed for direct detection of Erwinia amylovora in imported apple fruits with the sensitivity of the detection as low as 150 cfu in artificial contaminated samples.This level of detection sensitivity of at least 10 fold over direct PCR was confirmed in artificial apple samples with the advantage of not requiring DNA extraction steps while still allowing an accurate diagnosis of Erwinia amylovora.The successful detection for Erwinia amylovora in imported apple sample indicated that this IC-PCR assay is suitable for the large-scale screening Erwinia amylovora with a great potential to be used for routine apple sample assay.

为了筛选快速、灵敏的梨火疫病菌检测方法,利用常规PCR、套式PCR和实时荧光PCR方法分别对美国进境的326批樱桃果实中梨火疫病菌进行检测.结果显示,3种PCR方法的检出率不同,不同引物或探针的检出率也存在差异.在常规PCR中,引物Ams3/Ams4c、P29A/P29B和PEANT1/PEANT2的检出率分别为35.28%、24.85%和16.87%;单管套式PCR和套式PCR的检出率分别为23.01%和50.61%;4种实时荧光PCR的检出率分别为17.48%(探针PA)、32.21%(探针Ams)、29.14%(探针ITS)和23.93%(SYBR Green Ⅰ).在所有试验方法中由引物P29A/P29B和PEANT1/PEANT2组成的套式PCR的检出率最高.检测结果证实了进境樱桃果实中存在梨火疫病菌DNA,套式PCR和常规PCR(引物Ams3/4c)可用于进境樱桃样品中梨火疫病菌的常规检测.

41 fungal isolates with similar morphological characteristics to Leptosphaeria maculans were obtained by the deep-freezing filter paper method from 2100 seeds of Brassica napus imported from Australia.The isolate 8129-5 showed a slower growth on PDA at 20℃with growth rate of 2.8 mm/day.The colonies on PDA at 20℃ had an irregular or regular margin with white or grayish white compact aerial mycelium.No diffusible pigment was produced on PDA at 31℃ or in liquid Czapek-Dox media at 20℃.PCR detection showed that the isolate 8129-5 could be amplified by L.maculans-specific primers LmacF/LmacR and got expected product of 331 bp.The sequence analysis revealed that the ITS sequence of isolate 8129-5 had 99.8% identity with L.maculans.Pathogenicity of the isolate 8129-5 was confirmed on cotyledons of rape seed by artificial inoculation compared with typical symptom of L.maculans.Based on the morphological characteristics,PCR detection and the result of pathogenicity test,the isolate 8129-5 was identified as L.maculans.

5 ppm(20mg/m3)of methyl bromide residue concentration has widely been accepted as a safety exposure threshold limit internationally.Research on the degassing velocity of the container fumigation with methy1 bromide was conducted and with the results as follows:the concentration of the methy1 bromide residue in the container after degassing is very strictly depended on the degassing duration,absorbability and the loading volume of the cargo,but is not obviously interrelated to the air temperature,weather conditions or the size of the container.After 8 hours of degassing in natural condition and 3 weeks of ocean navigation,the residue concentration of MB in containers can mostly decrease to the acceptable level,but for cargo which have strong absorbability or of which wrapping plastic packing or those overloading containers,the duration of passive degassing should be prolonged or applying strong mechanical ventilation to achieve ideal effect.

口岸检验检疫部门对来自动植物病虫害疫区的国际航行船舶的厨房、配餐间、储藏室、食品舱等植物产品存放、使用的场所和部位实施现场检疫,这是目前国际航行船舶入境检验检疫(简称船检)业务的一个重要方面.

出入境货物的熏蒸监管,是目前口岸检验检疫工作一项重要任务.自美国、加拿大对我出口货物的木包装实施新的检疫措施以来,吴淞口岸出境货物木包装的熏蒸业务量急剧上升,对其监督管理也就成为我们工作的重点.