The Elimination of Viroids through In Vitro Thermotherapy and a Meristem Tip Culture from a New Limonime Hybrid (Citrus x limon var. limon (L.) Burm. f. x Citrus latifolia var. latifolia).
Virginia Sarropoulou, Katerina Grigoriadou, Varvara I Maliogka, Chrysoula-Lito Sassalou, Vasileios Ziogas
{"title":"The Elimination of Viroids through In Vitro Thermotherapy and a Meristem Tip Culture from a New Limonime Hybrid (<i>Citrus</i> x <i>limon</i> var. <i>limon</i> (L.) Burm. f. x <i>Citrus latifolia</i> var. <i>latifolia</i>).","authors":"Virginia Sarropoulou, Katerina Grigoriadou, Varvara I Maliogka, Chrysoula-Lito Sassalou, Vasileios Ziogas","doi":"10.3390/biotech13030037","DOIUrl":null,"url":null,"abstract":"<p><p>Viruses and viroids pose a significant challenge in citriculture, and their control is crucial for plant health. This study evaluated the effectiveness of in vitro thermotherapy combined with a meristem tip culture for eliminating citrus exocortis viroid (CEVd) and hop stunt viroid (HSVd) from a new limonime hybrid (<i>Citrus</i> x <i>limon</i> var. <i>limon</i> x <i>Citrus latifolia</i> var. <i>latifolia</i>). The elimination success was confirmed by RT-PCR assays. The in vitro elimination rate for CEVd during the shoot proliferation stage (43%) was higher than for HSVd (21%). Accordingly, in the subsequent rooting stage, the in vitro elimination rate for CEVd (50%) was higher than for HSVd (33%). Successful CEVd and HSVd eradication at a 100% rate was confirmed in the ex vitro acclimatized plants in the greenhouse. The study also established an efficient micropropagation protocol. The optimal treatment for in vitro shoot induction was 0.5-2 mg L<sup>-1</sup> benzyladenine (BA) + 0.5 mg L<sup>-1</sup> gibberellic acid (GA<sub>3</sub>) + 0.25 mg L<sup>-1</sup> naphthalene acetic acid (NAA), while for shoot elongation, it was 0.5 mg L<sup>-1</sup> BA + 0.5 mg L<sup>-1</sup> kinetin (KIN) + 0.5 mg L<sup>-1</sup> GA<sub>3</sub> + 0.25 mg L<sup>-1</sup> NAA. Rooting was best promoted by 1 mg L<sup>-1</sup> NAA. This study provides valuable insights for the mass production of viroid-free propagation material in this new lemon x lime hybrid, contributing to the conservation of genetic resources in citrus breeding programs through the combined application of in vitro thermotherapy and an in vitro meristem tip culture, a novel and highlighted achievement reported for the first time in this study.</p>","PeriodicalId":34490,"journal":{"name":"BioTech","volume":null,"pages":null},"PeriodicalIF":2.7000,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11430235/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"BioTech","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.3390/biotech13030037","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"BIOTECHNOLOGY & APPLIED MICROBIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Viruses and viroids pose a significant challenge in citriculture, and their control is crucial for plant health. This study evaluated the effectiveness of in vitro thermotherapy combined with a meristem tip culture for eliminating citrus exocortis viroid (CEVd) and hop stunt viroid (HSVd) from a new limonime hybrid (Citrus x limon var. limon x Citrus latifolia var. latifolia). The elimination success was confirmed by RT-PCR assays. The in vitro elimination rate for CEVd during the shoot proliferation stage (43%) was higher than for HSVd (21%). Accordingly, in the subsequent rooting stage, the in vitro elimination rate for CEVd (50%) was higher than for HSVd (33%). Successful CEVd and HSVd eradication at a 100% rate was confirmed in the ex vitro acclimatized plants in the greenhouse. The study also established an efficient micropropagation protocol. The optimal treatment for in vitro shoot induction was 0.5-2 mg L-1 benzyladenine (BA) + 0.5 mg L-1 gibberellic acid (GA3) + 0.25 mg L-1 naphthalene acetic acid (NAA), while for shoot elongation, it was 0.5 mg L-1 BA + 0.5 mg L-1 kinetin (KIN) + 0.5 mg L-1 GA3 + 0.25 mg L-1 NAA. Rooting was best promoted by 1 mg L-1 NAA. This study provides valuable insights for the mass production of viroid-free propagation material in this new lemon x lime hybrid, contributing to the conservation of genetic resources in citrus breeding programs through the combined application of in vitro thermotherapy and an in vitro meristem tip culture, a novel and highlighted achievement reported for the first time in this study.