Quantitative detection of four pome fruit viruses in apple trees throughout the year

A one-step real-time RT-PCR assay (RT-qPCR) with melting curve analysis, using the green fluorescence dye SYBR Green I, was developed to detect and quantify RNA targets from Apple mosaic virus (ApMV), Apple stem grooving virus (ASGV), Apple stem pitting virus (ASPV) and Apple chlorotic leaf spot virus (ACLSV) in infected apple trees. Single PCR products of 87 bp (ApMV), 70 bp (ASGV), 104 bp (ASPV) and 148 bp (ACLSV) were obtained, and melting curve analyses revealed distinct melting temperature peaks for each virus. A dilution series using in vitro synthesized transcripts containing the target sequences as standards yielded a reproducible quantitative assay, with a wide dynamic range of detection and low coefficients of variance. The content of selected viruses in apple plant tissues was stable throughout the year, and their accumulation did not significantly change between different plant tissues. The only minor exceptions were for ApMV and ACLSV, in which noticeable differences in their concentrations in various biological material were observed within the year. This divergence did not influence their year-round detectability. This one-step RT-qPCR assay is a valuable tool for year-round diagnostics, and molecular studies of the biology of ApMV, ASGV, ASPV and ACLSV

Apple mosaic virus

Apple mosaic, rose mosaic, plum and birch line pattern, horse chestnut yellow mosaic, and hazel mosaic are some of many diseases caused by one of the longest-known pome fruit viruses: Apple mosaic virus. The worldwide distribution of Apple mosaic virus and its negative impacts on fruit, nut and hop production are sufficient to cause international interest. This review endeavors to piece together all known information about the virus. We describe taxonomic position, virion structure, the host range and symptoms, modes of transmission and diagnostics for the virus, as well as distribution and control of the diseases it causes

Pharmacogenetics of the Central Nervous System—Toxicity and Relapse Affecting the CNS in Pediatric Acute Lymphoblastic Leukemia

Despite improving cure rates in childhood acute lymphoblastic leukemia (ALL), therapeutic side effects and relapse are ongoing challenges. These can also affect the central nervous system (CNS). Our aim was to identify germline gene polymorphisms that influence the risk of CNS events. Sixty single nucleotide polymorphisms (SNPs) in 20 genes were genotyped in a Hungarian non-matched ALL cohort of 36 cases with chemotherapy related acute toxic encephalopathy (ATE) and 544 controls. Five significant SNPs were further analyzed in an extended Austrian-Czech-NOPHO cohort (n = 107 cases, n = 211 controls) but none of the associations could be validated. Overall populations including all nations’ matched cohorts for ATE (n = 426) with seizure subgroup (n = 133) and posterior reversible encephalopathy syndrome (PRES, n = 251) were analyzed, as well. We found that patients with ABCB1 rs1045642, rs1128503 or rs2032582 TT genotypes were more prone to have seizures but those with rs1045642 TT developed PRES less frequently. The same SNPs were also examined in relation to ALL relapse on a case-control matched cohort of 320 patients from all groups. Those with rs1128503 CC or rs2032582 GG genotypes showed higher incidence of CNS relapse. Our results suggest that blood-brain-barrier drug transporter gene-polymorphisms might have an inverse association with seizures and CNS relapse

Diagnotics of the important apple viruses

Apple mosaic virus (ApMV), Apple stem grooving virus (ASGV), Apple stem pitting virus (ASPV) and Apple chlorotic leaf spot virus (ACLSV) are economically the most important viruses in pome fruit trees, which are distributed worldwide and can caused significantly yield reduction. The major control strategies (namely pathogen detection, exclusion by crop certification or quarantine, control in infected orchards by eradication from infected cultivars and rootstocks, etc.) rely heavily on accurate and sensitive detection methods and on perfect knowledge of pathogens. In the doctoral thesis the diagnostic method quantitative RT-PCR (qRT-PCR) was optimized for detection and quantification of four studied viruses. The results suggested that qRT-PCR method was the most reliable technique in comparison with conventional diagnostic methods DAS/I-ELISA and RT-PCR. In our study the concentration of ASGV, ASPV and ACLSV, measured by qRT-PCR, were stable during vegetation and in different plant tissue. Only the concentration of ApMV changed during vegetation in leaves and inner bark. This result indicates that changes of virus concentration observed by DAS/I-ELISA and RT-PCR in plant tissues are caused by other way (inhibitors, plant senescence, lower sensitivity, ect.) than by changes of virus concentrations in plant. Under the monitoring (at all 351 trees were tested) it was showed, that studied viruses were more spread in orchards and gardens then in wild apple trees. Selected virus isolates from wild apple trees and apples from orchards and gardens were sequenced and molecular variability was studied also with already published isolates. However individual isolates of studied viruses were similar. The variability associated with geographic origin or with type of planting has not been confirmed