Pest Risk Analysis Of Importation Of Ryegrass Seeds

Risk analysis is one of the most important technical trade measures of WTO/SPS. It plays an important role in regulating a country's trade policy and serves as the most important scientific evidence of dispute settlement. As a result, more and more countries lay stress on the research and application of risk analysis to quarantine. Pest Risk Analysis is the practical application of risk analysis to plant quarantine. It is not only a vital way to give evidence to scientific policy decision, but also the demand of plant quarantine harmonizing with international practice and quarantine management's internationalization, rationalization and openness. In order to harmonize with international practice as soon as possible and raise the scientific level of quarantine policy-making, the first thing for us to do is to carry out pest risk analysis when drafting phytosanitary measures.With the improvement of domestic herbage structure and especially the rapid development of urban afforestation, the demand for good strains of grass seeds from abroad, especially from the European and the US is becoming more and more urgent. Much more varieties and quantities of importation of foreign good strains of grass seeds will undoubtedly increase the risk of pests entering into China.So far, there are no reports about the PRA of ryegrass seeds. To prevent harmful pests and diseases with seeds from entering into China, minimizing the impact on the world trade, it is urgent to carry out pest risk analysis of ryegrass seeds according to the principals of WTO/SPS and the relevant domestic laws and regulations.The risk analysis was carried out under the line of Guidelines for Pest Risk Analysis (ISPM No.2).Among a list of 500 species associated with ryegrass seeds, a total of 234 species of pests were selected by referring to various kinds of documents including CAB-PEST-CD, lists of pests intercepted at port entry, etc. 7 species of quarantine pests and 3 species of regulated non-quarantine pests were identified for further evaluation. Based on the geographical and regulatory criteria, official control measures adopted in China, characteristics of pests, likelihood of entry, establishment, spread and economic importance, 5 species of quarantine pests, Anguina agrostis, Tilletia controversa, Senecio jacobaea L.,Rathayibacter rathayi and Xanthomonus traslucens pv.graminis were considered as high risk level. The others were considered as medium risk level. To further analyse, we ascertained our previous analysis result and made certain that the risk level of importation of ryegrass seeds was high as a whole.In view of the characteristics of quarantine pests and regulated non-quarantine pests associated with ryegrass seeds, the quarantine measures of reducing the risks to an acceptable level, such as prescribing entry ports, restricting the quantity of importation and strict quarantine management can be taken .