11/17/17, 11:54 AM First Report of 16Sr II (‘Candidatus Phytoplasma aurantifolia’) S…up-D Phytoplasma Associated with Alfalfa in Sudan | Plant Disease Page 1 of 2 https://apsjournals.apsnet.org/doi/full/10.1094/PDIS-04-17-0603-PDN Share Univ of Minnesota Welcome Guest user Sign in | Register | Mobile Journals Home APS Home IS-MPMI Home My Profile Subscribe Search Advanced Search Help About the cover for December 2017 ISSN: 0191-2917 e-ISSN: 1943-7692 SEARCH Enter Keywords MPMI Phytobiomes Phytopathology Plant Disease Advanced Search Resources Subscribe About Plant Disease First Look Most Downloaded Articles Journals Impact Submit a Manuscript Customer Care About My Password Rights and Permissions Plagiarism and Ethics Advertise Open Access ORCID Registry Editor-in-Chief: Alison E. Robertson Published by The American Phytopathological Society Home > Plant Disease > Table of Contents > Full Text HTML Previous Article | Next Article December 2017, Volume 101, Number 12 Page 2144 https://doi.org/10.1094/PDIS-04-17-0603-PDN DISEASE NOTES First Report of 16Sr II (‘Candidatus Phytoplasma aurantifolia’) Subgroup>D Phytoplasma Associated with Alfalfa in Sudan M. N. Tahir, USDA, National Germplasm Resources Laboratory, Beltsville, MD 20705; C. W. Holland, independant consultant; D. A. Samac, USDA, Plant Science Research Unit, St. Paul, MN 55108; and D. Mollov, † USDA, National Germplasm Resources Laboratory, Beltsville, MD 20705. Citation Open Access. In 2016, alfalfa (Medicago sativa) plants from four commercial fields in Sudan, each about 60 ha, were observed with leaf yellowing symptoms and stunted growth. Symptomatic plants were mostly concentrated around the edges of the fields with disease incidence of approximately 3 to 5%. Total nucleic acid was extracted from leaves of 14 symptomatic samples by a CTAB protocol. These extracts were used as the template in PCR assays with the universal phytoplasma primers P1/P7 (Smart et al. 1996). Eleven out of 14 samples produced an amplicon ∼1.8 kb long. Subsequently, primer pairs R16F2n/R16R2 were used in a nested PCR using the P1/P7 PCR amplicon as a template (Gundersen and Lee 1996). Amplicons were obtained from the same 11 samples that tested positive with the first round of PCR, and no amplification was obtained by the nested PCR from the three samples that were negative with the P1/P7 primers. Four of the 11 products amplified using the P1/P7 primers were gel purified and cloned into the pGem T-Vector (Promega, Fitchburg, WI) according to the manufacturer’s protocol. The consensus sequences were aligned using Geneious R9 (Biomaters, New Zealand). Three or four clones of each of the four positive samples (total of 14 clones) were sequenced in both directions. The percent identity among Quick Links Add to favorites E-mail to a colleague Alert me when new articles cite this article Download to citation manager Related articles found in APS Journals Article History Issue Date: 15 Nov 2017 Published: 4 Oct 2017 First Look: 1 Aug 2017 Accepted: 24 Jul 2017 Access provided by Univ of Minnesota Books Home