The threat of transboundary plant pathogens to agricultural trade in Southern Africa: a perspective on Zimbabwe’s plant biosecurity – A review

The high frequency of cargo, passengers and movement of goods across borders increases the chances of pest invasions and spread in a geographical area. This paper reviews the biosecurity concerns associated with cross border traffic in international trade, using Zimbabwe as a case study. It reviews the threats of transboundary plant pathogens due to cross border traffic and trade of agricultural products in Southern Africa. The importance of plant biosecurity in agriculture through institutions of plant quarantine measures in crop protection and plant biosecurity will be highlighted. The paper has related the importance of pathways of plant pathogens and their threats to agriculture systems through accidental introductions amongst other anthropogenic related pathways of pests' introduction and spread. The review also addresses the relationship between pest risk analysis, human aided pests' pathways, and bioterrorism threats. It explained how entry point quarantine officials must behave in so far as minimising the chances of new introductions, establishment and spread of exotic pests by employing modern conformity assessments test especially rapid testing techniques. There are many pathogens threatening production of staple and strategic crops in Southern Africa if no extra care is given to cross border management of pathogen pathways. The list of pathogens threatening the block of countries in Southern Africa is long. Zimbabwe and other Southern African countries should have a critical watch and improve cross border quarantine inspections, constantly reviewing quarantine laws and procedures as well as exploiting the gains in the science of the use of rapid pest testing techniques for pest pathways in cross border to improve on easy of doing business and trade.