vavilovВавиловский журнал генетики и селекцииVavilov Journal of Genetics and Breeding2500-3259Institute of Cytology and Genetics of Siberian Branch of the RAS10.18699/VJGB-22-34vavilov-3361Research ArticleГЕНОМИКА И ТРАНСКРИПТОМИКАPLANT GENETICS AND BREEDINGТрансмиссия вироида веретеновидности клубней картофеля между Phytophthora infestans и растениями-хозяевамиTransmission of potato spindle tuber viroid between Phytophthora infestans and host plantshttps://orcid.org/0000-0001-7368-0797АфанасенкоО. С.AfanasenkoO. S.

Пушкин, Санкт-Петербург

Pushkin, St. Petersburg

olga.s.afan@gmail.comhttps://orcid.org/0000-0003-1479-7746ХюттиА. В.KhiuttiA. V.

Пушкин, Санкт-Петербург

Pushkin, St. Petersburg

https://orcid.org/0000-0003-3383-2973МироненкоН. В.MironenkoN. V.

Пушкин, Санкт-Петербург

Pushkin, St. Petersburg

https://orcid.org/0000-0003-1419-7134ЛашинаН. М.LashinaN. M.

Пушкин, Санкт-Петербург

Pushkin, St. Petersburg

Всероссийский научно-исследовательский институт защиты растенийРоссияAll-Russian Research Institute of Plant ProtectionRussian Federation202204062022263272280Copyright © Афанасенко О.С., Хютти А.В., Мироненко Н.В., Лашина Н.М., 20222022Афанасенко О.С., Хютти А.В., Мироненко Н.В., Лашина Н.М.Afanasenko O.S., Khiutti A.V., Mironenko N.V., Lashina N.M.This work is licensed under a Creative Commons Attribution 4.0 License.https://vavilov.elpub.ru/jour/article/view/3361

Вироид веретеновидных клубней картофеля (ВВКК) представляет собой кольцевую одноцепочечную РНК длиной 356–363 нуклеотида, в которой отсутствуют какие-либо последовательности, кодирующие белок. ВВКК является экономически значимым заболеванием картофеля, имеющим статус карантинного. Известно, что ВВКК передается механически при вегетативном размножении растений, через инфицированную пыльцу и с помощью тлей. Целью данного исследования было определение возможности передачи ВВКК (штамм VP87) от растений картофеля и томата, зараженных вироидом, патогену Phytophthora infestans (Mont.) de Bary и от P. infestans – растениям картофеля и томата. Cорта картофеля Гала, Коломба и Ривьера, инфицированные ВВКК, инокулировали изолятом P. infestans PiVZR18; через 7 дней после появления симптомов фитофтороза провели повторное выделение P. infestans в чистую культуру на ржаной агар. Через 14 дней культивирования P. infestans на ржаном агаре в смеси мицелия и спорангиев методом ОТ-ПЦР был обнаружен ВВКК. ВВКК-инфицированным изолятом P. infestans (PiPSTVdv+) провели инокуляцию растений томата сорта Загадка и растений картофеля сорта Гала. Через 60 дней в листьях томата сорта Загадка методом ОТ-ПЦР с праймерами Р3/Р4 был выявлен диагностический продукт амплификации 360 п. о., свидетельствующий об успешной трансмиссии ВВКК изолятом PiVZR18v+. Результаты были подтверждены секвенированием продукта амплификации ВВКК. Нуклеотидная последовательность вироида в растении томата, зараженном изолятом PiVZR18v+, оказалась на 99.5 % идентичной использованному в эксперименте штамму VP87. Для доказательства возможности сохранения вироида в чистой культуре P. infestans изолят PiVZR18v+ пассировали на ржаном агаре с интервалом 30 дней. После трех последовательных пассажей на ржаном агаре ВВКК был диагностирован в культуре изолята, что подтверждено секвенированием продукта амплификации с вироид-специфичными праймерами. В субкультуре P. infestans после восьмого пассажа на ржаном агаре ВВКК не обнаруживался. Полученные данные свидетельствуют о двунаправленной передаче ВВКК в патосистеме P. infestans – растение-хозяин.

Potato spindle tuber viroid (PSTVd) is a naked, circular, single-stranded RNA (356–363 nucleotides in length) which lacks any protein-coding sequences. It is an economically important pathogen and is classified as a high-risk plant quarantine disease. Moreover, it is known that PSTVd is mechanically transmitted by vegetative plant propagation through infected pollen, and by aphids. The aim of this study is to determine the possibility of viroid transmission by potato pathogen Phytophthora infestans (Mont.) de Bary. PSTVd-infected (strain VP87) potato cultivars Gala, Colomba, and Riviera were inoculated with P. infestans isolate PiVZR18, and in 7 days, after the appearance of symptoms, re-isolation of P. infestans on rye agar was conducted. RT-PCR diagnostics of PSTVd in a mixture of mycelia and sporangia were positive after 14 days of cultivation on rye agar. The PSTVd-infected P. infestans isolate PiVZR18v+ was used to inoculate the healthy, viroid-free plants of potato cv. Gala and tomato cv. Zagadka. After 60 days, an amplification fragment of PSTVd was detected in the tissues of one plant of tomato cv. Zagadka by RT-PCR with the primer set P3/P4, indicating successful transmission of PSTVd by P. infestans isolate PiVZR18v+. This result was confirmed by sequencing of the RT-PCR amplicon with primers P3/P4. The partial sequence of this amplicon was identical (99.5 %) to PSTVd strain VP87. RT-PCR showed the possibility of viroid stability in a pure culture of P. infestans isolate PiVZR18v+ after three consecutive passages on rye agar. PSTVd was not detected after the eighth passage on rye agar in P. infestans subculture. These results are initial evidence of potato viroid PSTVd being bidirectionally transferred between P. infestans and host plants.

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The authors declare that there are no conflicts of interest present.