Phytopathology. 2000 Feb;90(2):134-8. doi: 10.1094/PHYTO.2000.90.2.134.
ABSTRACT A total of 14 Spanish isolates of Citrus tristeza virus (CTV) and 1 isolate from Japan were transmitted by Aphis gossypii, and the subisolates obtained were compared with the source isolates for symptom expression and double-stranded RNA (dsRNA) pattern. Of the 14 Spanish isolates, 9 showed altered dsRNA patterns after aphid transmission but only minor variations in the intensity of symptoms induced on Mexican lime. Northern blot hybridization with complementary DNA (cDNA) probes corresponding to both the 5' and the 3' termini of the CTV genomic RNA (gRNA) showed that the dsRNA bands that could be used to discriminate between the dsRNA pattern of the source and the aphid-transmitted isolates were the replicative forms of defective RNAs (D-RNAs). Conversely, the Japanese isolate and two subisolates obtained from it by aphid transmission had the same dsRNA pattern, but one of the subisolates induced milder symptoms in several hosts. Dot-blot hybridization with cDNA probes representing several regions of the gRNA showed that most of the aphid-transmitted isolates differed from the corresponding source isolate by their hybridization pattern. Our results indicate that aphid transmission often sorts the populations of gRNA variants and D-RNAs present in CTV isolates.
通过棉蚜（Aphis gossypii）传播了 14 株来自西班牙的柑桔衰退病毒（CTV）分离株和 1 株来自日本的分离株，并对获得的亚分离株与原始分离株进行了症状表达和双链 RNA（dsRNA）模式的比较。在 14 株西班牙分离株中，有 9 株在蚜虫传播后出现 dsRNA 图谱改变，但在墨西哥青柠上诱导的症状强度仅略有变化。Northern blot 杂交用 cDNA 探针（对应 CTV 基因组 RNA（gRNA）的 5'和 3'末端）显示，可用于区分原始和蚜虫传播分离株 dsRNA 图谱的 dsRNA 带是缺陷 RNA（D-RNA）的复制形式。相反，来自日本的分离株及其通过蚜虫传播获得的两个亚分离株具有相同的 dsRNA 图谱，但其中一个亚分离株在几种宿主中引起的症状较轻。用 cDNA 探针进行斑点杂交代表 gRNA 的几个区域显示，大多数蚜虫传播的分离株与其相应的原始分离株在杂交图谱上存在差异。我们的结果表明，蚜虫传播通常会对 CTV 分离株中存在的 gRNA 变体和 D-RNA 群体进行分类。
