文献类型： 外文期刊

作者： Xu, Weinan ¹ ; Guo, Yuxia ⁴ ; Li, Hua ² ; Sivasithamparam, Krishnapillai ² ; Jones, Michael G. K. ² ; Chen, Xin ¹ ; Wylie, Stephen J. ² ;

作者机构： 1.Jiangsu Acad Agr Sci, Inst Ind Crops, Nanjing 210014, Peoples R China

2.Murdoch Univ, Western Australian State Agr Biotechnol Ctr, Plant Biotechnol Res Grp Virol, Murdoch, WA 6150, Australia

3.Jiangsu Acad Agr Sci, Jiangsu Key Lab Hort Crop Genet Improvement, Nanjing 210014, Peoples R China

4.Henan Agr Univ, Coll Anim Sci & Vet Med, Zhengzhou 450002, Peoples R China

关键词： intraspecies diversity; symptom expression; virus accumulation; Rdr1 gene

期刊名称：PLANT DISEASE （ 影响因子：4.614； 五年影响因子：5.33 ）

ISSN： 0191-2917

年卷期： 2022 年 106 卷 3 期

页码：

收录情况： SCI

摘要： Yellow tailflower mild mottle virus (YTMMV, genus Tobamovirus) was identified from wild plants of solanaceous species in Australia. Nicotiana benthamiana is a species indigenous to the arid north of Australia. N. benthamiana accession RA-4 (the lab type), which has a mutant, functionally defective, RNA-dependent RNA polymerase 1 (Rdr1) gene (Nb-Rdr1m), has played a significant role in plant virology, but little study has been done regarding responses to virus infection by other accessions of N. benthamiana. All wild-collected N. benthamiana accessions used in this study harbored wild-type Rdr1 genes (Nb-Rdr1). We compared symptoms of YTMMV infection and viral RNA load on RA-4 and nine wild-collected accessions of N. benthamiana from mainland Western Australia, an island, and the Northern Territory. After inoculation with YTMMV, RA-4 plants responded with systemic hypersensitivity and all individuals were dead 35 days postinoculation (dpi). Plants of wild-collected accessions exhibited a range of symptoms, from mild to severe, and some, but not all, died in the same period. Quantitative reverse transcription PCR revealed that the Rdr1 mutation was not a predictor of viral RNA load or symptom severity. For example, wild-collected A019412 plants carried more than twice the viral RNA load of RA-4 plants, but symptom expression was moderate. For plants of most accessions, viral RNA load did not increase after 10 dpi. The exception was plants of accession Barrow-1, in which viral RNA load was low until 15 dpi, after which it increased more than 29-fold. This study revealed differential responses by N. benthamiana accessions to infection by an isolate of YTMMV. The Rdr1 gene, whether mutant or wild-type, did not appear to influence viral RNA load or disease expression. Genetic diversity of the 10 N. benthamiana accessions in some cases reflected geographical location, but in other accessions this was not so.