Viral Pests Risk Analysis For The Importation Of Narcissus And Detection And Identification Of Narcissus Virus

Narcissus is a perennial herbaceous ornament plant that belongs to the genus Narcissus and family Amaryllidaceae.In recent years,China has introduced a large number of narcissus from abroad every year.At the same time,a variety of plant viruses were detected in imported narcissus bulbs.Because narcissus bulb is a high-risk species of plant propagation materials,the deployment of virus infected bulbs easily lead to long-distance spread of the virus.In this study,viral pest that may be carried on import narcissuses were collected and collated,and 25 major virus species in propagation materials of narcissus were ensured.According to the specific steps and methods of Guidelines for pest risk analysis(FAO),Guideline for the risk analysis of plant virus and viroid(GB/T23633-2009)and Technical requirement of pest risk analysis for import and export plant and plant product(GB/T20879-2007),controlled viral pest of foreign Narcissuses are analysed.And five species of potential quarantine pest were ensured as follows,Arabis mosaic virus(ArMV),Strawberry latent ringspot virus(SLRSV),Tobacco ringspot virus(TRSV),Tomato black ring virus(TBRV)and Tomato ringspot virus(ToRSV).Then a management plan was proposed to reduce the risk of incoming regulated pests,so as to provide references for the quarantine of import narcissuses at the port.In this study,the european narcissus bulbs intercepted by Fujian port in 2013,were used as materials,according to the results of pest risk analysis,the potential quarantine viruses were detected and identified by using serological,electron microscopy and molecular biology methods.The results showed that the quarantine virus--ArMV was positive,and the ArMV-positive samples contained isometric virions with a diameter of about 30 nm.By sequencing analysis,the size of amplified fragment is in accordance with expected fragment of ArMV,and highly homologous to the reported virus ucleotide sequence.Researches showed that the quarantine virus--ArMV was carried on the european narcissus bulbs which should be destroyed.And the results of risk analysis of import narcissus viruses was verfied to be valid.