ISTA - Variety Committee DNA Working Group

Transcription

1 ISTA - Variety Committee DNA Working Group... the Technical Committee for Species and Variety Testing Report of Activities during goals achieved aims for the future Cheryl Dollard

2 The strategy for incorporating DNA based tests into the ISTA rules... Establishing the DNA WG in 2007, during the last ISTA Symposium in Brazil Selection of microsatellites markers as they have proven to be one of the most appropriate for variety identity and genetic relationship studies Selection of crops based on those representing the most important ones in terms of cultivated area and world production (maize, soybean, wheat and rice) Conducting four comparative tests (CTs) for the selection of the most reliable markers per crop

3 The Variety TCOM DNA Working Group Kalyin Brix Davis, USA Silvie Cassé, France Chiara Delogu, Italy Kae-kang Hwu, Taiwan Kunusoth Keshavulu, India Maria Alicia Loray, Argentina Cesar Olsina, Argentina Verena Petersel, Austria Elisa Vieira, Brasil Emanuela Casarini, Italy Marie-José Côté, Canada Cheryl Dollard, Canada Benjamin Kaufman, USA Kim Kenward, Canada Gaspar Malone, Argentina Daniel Perry, Canada Ana Laura Vicario, Argentina Heather Waxdahl, USA

4 Comparative Tests First two CTs were performed by laboratories having experience with each crop and/or technique Stabilization of the SSR set: some SSR were substituted with others in order to improve repeatability and to verify if the marker set was polymorphic enough to provide unique patterns for a larger variety sets Comparable results between participant laboratories: participants obtained the same band patterns and allele sizes even when using different reactants, equipment and working protocol Different visualization systems prove to give the same bands patterns (even when the allele sizes may not have been the same)

5 Comparative Tests The third CT was organized: to prove robustness of the method by including additional laboratories that would run the selected SSRs and the same varieties tested by the original laboratories to select the most suitable SSRs for variety identification by testing some new SSR from the original laboratories SSR were qualified as good and very good, meaning that repeatable and reproducible results were obtained for that marker during 2-3 rounds of comparative tests Results from the CT were presented during the UPOV-BMT Meeting in Ottawa the of May by Cheryl Dollard

6 Crop group Wheat Summary of Results Participating laboratories per CT CT1 CT2 CT3 Canada x2 Canada x2 Austria, Argentina France France Canada x3 Visualization methods used Licor 4200 and 4300, ABI 3130xl and Silver stain Italy Italy France, Italy Rice Canada, Italy Taiwan Canada, Italy Taiwan Canada, India Italy, USAx2, Taiwan ABI3100 and 3130, Licor 4300 and Agarose Soy Argentina Argentina Argentina x3 Silver stain and ABI 3100 Brazil, Canada Brazil, Canada, USA Brazil, Canada, USA Maize Argentina Brazil, Canada France Argentina Brazil, Canada France Brazil, Canada China, France x2, Italy, USA x2 ABI3130xl, Silver stain, ABI 3100 and Silver Stain

7 Comparative Tests and Performance Tests After the third CT the maize group has established an SSR set that is ready to be applied for the organization of a Performance Test For the Performance Test it is necessary to have a core set of varieties to be used as reference material (RM) The organization of performance tests (PT) on this species was discussed during the ECOM/TCOM meeting the last 15 th of June

8 The 4 th comparative test: Wheat and Soybean groups have organized a fourth CT to analyze some more SSR for the identification of few last varieties This work is still in progress, but is planned to be concluded in few months. PT and RM will be discussed and organized also on wheat and soybean.

9 The 4 th comparative test: Wheat Three laboratories are testing a new set of six SSR to be proposed to supplement the previously selected SSR set Examining three pairs of varieties that were indistinguishable by markers used in first three Cts. Collaborating laboratories are: Daniel Perry, Canadian Grain Commission, Canada Marie-José Côté, CFIA, Canada Kim Kenward, 20/20 Seed Labs Inc., Canada

10 The 4 th comparative test: Soybean Seven laboratories are testing the same 24 varieties used in previous CTs with 8 SSR, 3 of which already ran And also running a new set of 5 SSR to be proposed as integration to the previously selected SSR set Collaborating laboratories are: Ana Vicario, INASE, Argentina ElisaVieira, Coodetec, Brasil Marie-José Côté, CFIA, Canada Kalyn Brix Davis, SGS, USA Cesar Olsina BCR, Argentina Gaspar Malone, Argentina Beni Kaufman, USA

11 Further steps Define a set of reference varieties for each crop that can be used by laboratories that wish to establish protocols for variety verification Define a strategy together with ISTA s Statistics Committee for the accreditation of laboratories performing DNA-based variety verification tests. Establish a proficiency testing (PT) program to assist laboratories develop testing capacity for varietal verification for these crops using molecular markers, and to promote use of these internationally standardized methods

12 Acknowledgement We would like to thank all the WG leaders and all the collaborating laboratories. Special acknowledgments for their special collaboration with the DNA WG activity go to: Ana-Laura Vicario (Argentina) Cheryl Dollard (Canada) Daniel Perry (Canada) Berta Killerman (Germany) We would like to acknowledge to all private and public institutions that kindly collaborated with these tests and to ISTA who gave technical and administrative support.