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1.
A nucleopolyhedrovirus (NPV) was isolated from a diseased larva of the smaller tea tortrix, Adoxophyes honmai, collected from a tea field in Tsukuba, Ibaraki, Japan. Electron microscopic observations confirmed that A. honmai NPV (AdhoNPV) was a single-nucleocapsid type virus. The genome size of AdhoNPV was estimated to be 111.6 +/- 0.9kb (mean +/- SE) by restriction endonuclease analysis. AdhoNPV was also infectious to two other Adoxophyes species, the summer fruit tortrix Adoxophyes orana and Adoxophyes dubia. The LD50 values for neonatal, second, third, fourth, and fifth (final) instar larvae of A. honmai were determined as 61, 107, 688, 1,961, and 4,085 occlusion bodies/insect, respectively. Most of the infected larvae died 5-9 days after molting to the final instar, regardless of the timing of inoculation. However, when neonates were exposed to extremely high doses of AdhoNPV (greater than 100 x LD90), larval development was prevented and most of the larvae died in the first instar.  相似文献   

2.
Lee SY  Park H  Boo KS  Park KT  Cho S 《Molecules and cells》2005,19(3):391-397
Molecular identification techniques are used where morphological characters are not useful for distinguishing species that resemble each other closely. The example studied here is the Adoxophyes species complex, in which A. orana (Fischer von R?sslerstamm) is officially the only known Korean species in the genus Adoxophyes (Lepidoptera: Tortricidae). However there have been suspicions that at least two types of A. orana exist in Korea based on the distribution and range of the host, with A. orana attacking apples and peaches, and another Adoxophyes sp. attacking tea and pears. The latter is presumed to be A. honmai (Yasuda), but the two have remained confused because of their extreme morphological similarity, despite several Asian studies of pheromonal and morphological characteristics. To confirm the occurrence of an Adoxophyes species other than A. orana in Korea, we compared 940 bp of the mitochondrial cytochrome oxidase I (COI) gene from 16 samples of Adoxophyes and found that there is a second Adoxophyes species different from A. orana. Comparison of the different sequences to that of Japanese A. honmai confirmed that they belong to the latter. From the sequence difference between the two Korean species, we were able to develop new PCR primer sets that distinguish them. This molecular identification technique with no enzyme digestion or sequencing step is a convenient and rapid way of differentiating between species that are hard to distinguish morphologically.  相似文献   

3.
Full-length mariner-like elements (MLEs) were identified from both a parasitoid wasp, Ascogaster reticulatus, and its moth host, Adoxophyes honmai. MLEs were detected in two related Tortricid moths, but not in another Ascogaster species. The MLEs of A. reticulatus and A. honmai were 97.6% identical in DNA sequence. This high similarity suggests a recent horizontal transfer, probably from the moth host to the wasp parasitoid, facilitated by the intimacy of the host-parasitoid relationship.  相似文献   

4.
Tea is a perennial and evergreen plant. Cultivated tea trees provide a habitat for insect pests and their natural enemies. In Japan, granuloviruses (GVs) have successfully controlled two of the most important pests of tea, Adoxophyes honmai and Homona magnanima (Tortricidae: Lepidoptera). The GVs are produced in vivo and a single application sustains pesticidal efficacy throughout a year, which encompasses 4 to 5 discrete generations of both species. A. honmai and H. magnanima also have various natural enemies, especially hymenopteran parasitoids. Such resident natural enemies also play a role in reducing the pest density in virus-controlled fields, but the effect of virus infection on parasitoids sharing the same host larva has not been well studied. Survival of one of the major parasitoids ofA. honmai, Ascogaster reticulata (Braconidae: Hymenoptera), is reduced by virus infection of the host. Viruses, including GV and entomopoxvirus (EPV), and certain koinobiont endoparasitoids, including A. reticulata, are both known to regulate host endocrinology. However, the GV and EPV have distinct host regulation mechanisms, and consequently have different impacts on the survival of A. retuculata, when A. reticulata parasitizes a host that is infected with either GV or EPV. These additional effects on host regulation displayed by both viruses and parasitoids affect the outcome of virus-parasitoid interactions.  相似文献   

5.
Long G  Pan X  Westenberg M  Vlak JM 《Journal of virology》2006,80(22):11226-11234
F proteins from baculovirus nucleopolyhedrovirus (NPV) group II members are the major budded virus (BV) viral envelope fusion proteins. They undergo furin-like proteolysis processing in order to be functional. F proteins from different baculovirus species have a long cytoplasmic tail domain (CTD), ranging from 48 (Spodoptera litura multicapsid NPV [MNPV]) to 78 (Adoxophyes honmai NPV) amino acid (aa) residues, with a nonassigned function. This CTD is much longer than the CTD of GP64-like envelope fusion proteins (7 aa), which appear to be nonessential for BV infectivity. Here we have investigated the functional role of the CTD of Helicoverpa armigera single-capsid NPV (HearNPV), a group II NPV. We combined a newly constructed HearNPV f-null bacmid knockout-repair system and an Autographa californica MNPV (AcMNPV) gp64-null bacmid knockout-pseudotype system with mutation and rescue experiments to study the functional role of the baculovirus F protein CTD. We show that except for the 16 C-terminal aa, the HearNPV F CTD is essential for virus spread from cell to cell. In addition, the CTD of HearNPV F is involved in BV production in a length-dependent manner and is essential for BV infectivity. The tyrosine residue Y658, located 16 aa from the C terminus, seems to be critical. However, HearNPV F without a CTD still rescues the infectivity of gp64-null AcMNPV BV, indicating that the CTD is not involved in processing and fusogenicity. Altogether, our results indicate that the F protein is essential for baculovirus BV infectivity and that the CTD is important for F protein incorporation into BV.  相似文献   

6.
The number of larvae containing polyhedra increased when larvae of Adoxophyes orana and Barathra brassicae were fed on polyhedra of nuclear polyhedrosis virus (NPV) of the reciprocal species. Comparison of restriction endonuclease EcoRI cleavage patterns of DNA isolated from polyhedra used as inocula and from polyhedra obtained after cross-inoculation showed that cross infection did not occur. The observations indicate that latent viruses were activated in both insects. Activation of the A. orana latent NPV with polyhedra of a cytoplasmic polyhedrosis virus (CPV) of B. brassicae, and cross-inoculation with an extract prepared from healthy larvae indicated that an activating agent does not have to be a component of nuclear polyhedra.  相似文献   

7.
秦峰  付文博  周善义 《昆虫学报》2011,54(3):339-351
对凤蝶科6属25种的COⅠ基因和20种Cyt b基因的部分序列进行测定和分析, 探讨它们之间的系统发育关系; 以茶小卷叶蛾Adoxophyes honmai为外群, 用邻接法(neighbor-joining, NJ)、 最大简约法(maximum parsimony, MP)和贝叶斯法(Bayesian inference, BI)重建了凤蝶科6属的分子系统树。结果表明: COⅠ基因部分序列长度为661 bp, 其中保守位点417个, 可变位点244个, 简约信息位点191个; A+T的平均含量为70.3%, 明显高于C+G的平均含量29.6%。Cyt b基因部分序列长度为433 bp, 其中保守位点239个, 可变位点194个, 简约信息位点135个; A+T的平均含量为74.2%, 明显高于C+G的平均含量25.7%。分子系统树表明, 凤蝶属Papilio、 斑凤蝶属Chilasa、 尾凤蝶属Bhutanitis、 珠凤蝶属Pachliopta和喙凤蝶属Teinopalpus为单系性, 与传统形态分类结果相一致。但青凤蝶属Graphium单系性不够明确, 需要进一步探讨。研究结果为我国凤蝶科分子系统学研究积累了资料。  相似文献   

8.
《Biological Control》2008,47(3):542-546
The smaller tea tortrix, Adoxophyes honmai (Lepidoptera: Tortricidae), is one of the most important pests of tea plants in Japan. Adoxophyes honmai nucleopolyhedrovirus (AdhoNPV) isolates from Tsukuba (AdhoNPV-Ts) and Tokyo (AdhoNPV-To), Japan, and Adoxophyes orana nucleopolyhedrovirus (AdorNPV) isolates from England (AdorNPV-En) and the Netherlands (AdorNPV-Ne) were subjected to genetic and biological comparisons to select a candidate NPV isolate to control A. honmai. Restriction endonuclease (REN) analysis demonstrated that AdhoNPV-Ts and AdhoNPV-To had similar REN patterns, whereas AdorNPV-En and AdorNPV-Ne exhibited different REN patterns from each other as well as those of AdhoNPV-Ts and AdhoNPV-To. Bioassays with fourth-instar A. honmai larvae showed that AdorNPV-En was most pathogenic, with the lowest LD50 of 37 occlusion bodies (OBs) per larva. When A. honmai neonates were inoculated with each isolate, most larvae infected with AdhoNPV-Ts and AdhoNPV-To were killed in the final (fifth)-instar, whereas larvae infected with AdorNPV-Ne were killed at every instar and larvae infected with AdorNPV-En were killed at the first- to third-instar. AdorNPV-En or AdhoNPV-Ts fed to neonates had the shortest or longest killing times, respectively, with ST50 values of 6 and 19 days. AdhoNPV-To and AdorNPV-Ne had intermediate killing times. The OB yield per larva of AdhoNPV-Ts and AdhoNPV-To was significantly higher than that of AdorNPV-En and AdorNPV-Ne. Our results suggest that AdorNPV-En is suitable as an inundative agent because it is a quick-killing, highly virulent NPV, and AdhoNPV-Ts and AdhoNPV-To are more appropriately used as inoculative agents because of their high OB production.  相似文献   

9.
Three entomopoxviruses (EPVs) isolated from diseased Adoxophyes honmai larvae at different localities (Tsukuba, Itsukaichi, and Miyazaki) in Japan were compared for biochemical identity and key parameters of virus fitness, fatal infection, speed of kill, and virus yield. When the structural peptides of occlusion bodies (OBs) and occlusion-derived viral particles were compared using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, no difference in banding patterns was observed. However, DNA restriction endonuclease analysis showed that the three isolates were genotypically different, but many commonly sized DNA fragments were observed. Five tortricid species, A. honmai, Adoxophyes orana, Adoxophyesdubia, Homona magnanima, and Archips insulanus were susceptible to all isolates. No significant differences in the key viral fitness parameters were detected among the isolates in A. orana. However, the Miyazaki isolate had a different effect on H. magnanima; it allowed infected insects to survive longer and develop to a larger size, but had a lower yield of OBs per larva at any given time to death. OB yields per unit cadaver weight for the Miyazaki isolate, which indicate the conversion rate of the insect to virus, were lower over time compared to the other two isolates. The implications for selecting a candidate isolate to control tortricid pests are discussed.  相似文献   

10.
The common cutworm (Agrotis segetum) and the black cutworm (Agrotis ipsilon) are serious soil pests of many vegetable and field crops all over the world. We have demonstrated the cross-infectivity of two baculoviruses, A. segetum nucleopolyhedrovirus (AgseNPV) and A. ipsilon nucleopolyhedrovirus (AgipNPV) for these two insect pests. The susceptibility of A. segetum to AgipNPV was confirmed by DNA restriction endonuclease analyses of DNA isolated from virus harvested from infected A. segetum larvae. For an initial comparison of both viruses, partial polyhedrin sequences were amplified by PCR, cloned, and sequenced. Both viruses shared a very similar polyhedrin gene sequence resulting in only three amino acid substitutions. Phylogenetic analyses clearly demonstrated that both viruses belong to NPV group II and are most closely related to a clade consisting of Spodoptera exigua NPV, Spodoptera frugiperda NPV, and Spodoptera littoralis NPV. Since AgipNPV shows high virulence for both cutworm species, it appears to be a suitable candidate as a single biological control agent of A. segetum and A. ipsilon.  相似文献   

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