b"between ISTA and ISHI to support thecal results, these technologies should be seed industry on disease issues and testused as a pre-screen and in combination methods, Jones explains, adding thatwith other assays, including a direct test, ISTA methods are validated in interlabo- Claessens says.ratory tests in collaboration with both official governmental laboratories andSuccess Storiesseed company laboratories. With seed health organizations and The Seed Health Committee (SHC) ofteams working around the world to ISTA has defined guidelines for validationcreate healthy seed, challenges are met of methods based on the study of perfor- with dedication and passion.mance criteria. We can't underestimate the impor-The SHC is currently harmonizing andRic Dunkle. Steve Jones. tance of healthy plants relative to sustain-validating five seed health methods forable agriculture. Everything starts with vegetable and field crops, Jones says. the seed, with high rates of germination, productivity, resistance to pests and Standardized Equals Success diseases, as well as plants that require the Ric Dunkle, senior director of Seed Healthfewest amounts of inputs, Dunkle says.and Trade at the American Seed TradeIn Europe, the banning of Methyl Association (ASTA), explains why non- Bromide allowed a nematode Ditylenchus standardized testing is a real problem. dipsaci to resurge, and it became a re-If the seed is tested using one methodemerging pest. before export in one country, and thenCombining validation of a harmonized tested using a different method on importdetection method (ISTA-7-031) and using in another country, they may get differentit to validate seed physical disinfection results. It creates a lot of uncertainly toGary P Munkvold. Rose Souza- methods, combined with a certification move those seeds around, Dunkle says.Richards. scheme, now allows the distribution of In some cases, seed may be tested fivehealthy seeds, Jones says.or more times while en route to its finalSeed companies are in the business of destination. creating healthy seed and initiatives sup-One example of this problem isThrough the use of these methodsport that goal. Best practices used during the Tomato Brown Rugose Fruit Virusand our expertise we strive to assist seedcrop production are designed to protect (ToBRFV), which was first reported incompanies in their risk management,seed from exposure to pests and dis-late 2019 in production fields and green- advocate for the seed industry on seedeases, and have the potential to manage houses in many countries, such as Mexico,health related issues and facilitate theand significantly reduce overall pest risk.Germany, U.S., the Netherlands and Italy. international movement of seeds, saysIf seed contains unwanted pests As a new disease, there are now overFrank Claessens, chairperson of ISFs Seedincluding weeds or other foreign germ-25 countries regulating for it, using aHealth Group Board and board memberplasm, seed quality is compromised, potpourri of molecular seed health testingof BASFs vegetable seed business.Souza-Richards says. methods, Dunkle says.Ideally, the test should distinguishNot only does this hurt the customers, The North American Plant Protectionbetween the presence of viable and non- but ultimately food security.Organization (NAPPO) set to work evalu- viable organisms, he says. With seed as one of the most critical ating several of those methods.While indirect testing methods suchinputs to agricultural production, farmers, Each country will run each of thoseas PCR and High Throughput Sequencinggovernments, researchers and the seed testing methods and compare the resultsor Next Generation Sequencing providesector are similarly seeking solutions to to figure out which one or two will be thea faster and relatively inexpensive way tothe agricultural and ecological challenges most consistent and then recommendsignal the presence of a pathogen, theyfacing our world. It is only through our those to the rest of the world, Dunkle says. are not sufficient to prove pathogenicity. collective and conscious efforts that we ISHI-Veg has also identified 6 valida- ISF maintains these results can bewill make a difference.SWtion criteria against which the perfor- viewed as a pre-screening, whereas a mance of the methods is measured. negative result in an indirect test requires no additional testing to confirm that the Testing Trials seed lot in question is healthy.WHERE ISHI-Veg have outlined best practices forTo ensure a correct assessment ofON THE WEBPCR, ELISA and dilution-plating assaysthe health status of a seed lot and avoid used in routine seed health testing, withunwarranted phytosanitary regulationsThis piece has been condensed for print. To see the full version of this piece, please visit: SeedWorld.combest practices in preparation.based solely on molecular or serologi-76/ SEEDWORLD.COMINTERNATIONAL EDITION 2021"