Viruses Infecting Trees and Herbs That Produce Edible Fleshy Fruits with a Prominent Value in the Global Market: An Evolutionary Perspective

Trees and herbs that produce fruits represent the most valuable agricultural food commodities in the world. However, the yield of these crops is not fully achieved due to biotic factors such as bacteria, fungi, and viruses. Viruses are capable of causing alterations in plant growth and development, thereby impacting the yield of their hosts significantly. In this work, we first compiled the world′s most comprehensive list of known edible fruits that fits our definition. Then, plant viruses infecting those trees and herbs that produce fruits with commercial importance in the global market were identified. The identified plant viruses belong to 30 families, most of them containing single-stranded RNA genomes. Importantly, we show the overall picture of the host range for some virus families following an evolutionary approach. Further, the current knowledge about plant-virus interactions, focusing on the main disorders they cause, as well as yield losses, is summarized. Additionally, since accurate diagnosis methods are of pivotal importance for viral diseases control, the current and emerging technologies for the detection of these plant pathogens are described. Finally, the most promising strategies employed to control viral diseases in the field are presented, focusing on solutions that are long-lasting.

Harmful viruses on stone fruit crops and sanitation methods

Relevance. Viral diseases can significantly reduce the yield of stone fruit crops. More than 30 viruses have been characterized on stone fruits crops, among which the most harmful are Plum pox virus (PPV), Prunus dwarf virus (PDV), Prunus necrotic ringspot virus (PNRSV), Cherry leaf roll spot virus (CLRV), Apple chlorotic leaf spot virus (ACLSV). Viral diseases monitoring is essential for controlling the viruses prevalence and choosing a control strategy. In the absence of healthy plants of a certain variety, health improvement is carried out using laboratory methods, including thermotherapy. Sanitation methods need to be improved in relation to the culture characteristics and the virus type. Of considerable interest is the development of techniques that reduce the viruses concentration when growing stone fruit trees in the field.Methods. During 2016–2020 using the ELISA (“Loewe” diagnostic kits) diagnostics of viruses on varieties and clonal rootstocks of cherry, sweet cherry and plum (660 plants) was carried out in the conditions of the Moscow region. For plant health in 2019–2021 used thermotherapy for 3 months. To study the effect of Pharmayod (“Farmbiomed”) on viruses in open ground, 24 plum plants of 5 varieties were treated with this drug at a concentration of 0.3 ml/l.Results. The total prevalence of viruses on cherries varieties was 44%, sweet cherries — 40%, plums — 59%, on clonal rootstocks — 46, 55 and 56% respectively. The highest incidence of PNRSV and PDV viruses has been established. Cherry plants of 11 varieties, free from the main harmful viruses, 4 varieties of sweet cherries, 12 varieties of plums and 9 forms of clonal rootstocks were revealed. The use of the Pharmayod on plum trees in the open field contributed to a decrease in the infection index of the studied viruses. Plum plants in a heat chamber were characterized by a higher survival rate and growth parameters in comparison with cherry and sweet cherry. After the completion of thermotherapy, a significant decrease in the index of infection in plants was noted.

Seropositivity for CMV, EBV, HBV, HCV, and HIV in Leukemia Patients and Its Relationship with Cytogenetic Changes

Introduction: Leukemias are involving the bone marrow and the soft tissues in inner parts of the bones, where new blood cells are formed. This malignancy is the most common pediatric cancer, which its etiologic causes are not well understood. This multifactorial disease is believed to linked with genetic and non-hereditary environmental factors. Cytogenic analyses of chromosomal abnormalities provide diagnostic and prognostic values in leukemia patients. Given the high prevalence of viral diseases and clinical suspicions on the relationship between certain viral infections and leukemia, it is necessary to investigate this possible relationship, especially in third-world countries. The present study recruited 65 children with leukemia (AML, CML, or ALL) who were presented to two tertiary hospitals. At first, all the patients underwent testing for HBV, HCV, CMV, EBV, and HIV. Bone marrow specimens were studied for identifying possible chromosomal abnormalities in cytogenic investigations. According to our findings, there was a relationship between incidence of leukemia, the 12:21 chromosomal translocation and CMV infection. Therefore, preventing CMV infection can lead to a reduced incidence of leukemia. It is expected that the findings of this study enlighten the scientists to conduct more extensive research on the relationship between viral diseases and leukemia in third-world countries.Method:The present study recruited 65 children with leukemia (AML, CML, or ALL) who were presented to two tertiary hospitals. At first, all the patients underwent testing forHBV, HCV, CMV, EBV, and HIV. Bone marrow specimens were studied for identifying possible chromosomal abnormalities in cytogenic investigations.Result:According to our findings,there was a relationship between the incidence of leukemia,the 12:21 chromosomal translocation, and CMV infection.Therefore, preventing CMV infection can lead to a reducedincidence of leukemia.Conclusion:In this study, we demonstrated that leukemia is relevant to the 12:21 chromosomal translocation and CMV virus infections, So the reduction in leukemia prevalence is dependent on the prevention of CMV disease. It is expected that the findings ofthis studyenlighten the scientists to conduct more extensive researchon the relationship between viral diseasesand leukemia in third-world countries.Trial registrations:Clinical trial registration code:IR.AJAUMS.REC.1399.161Evaluated by: AJA UNIVERSITY OF MEDICAL SCIENCESApproval Date:2020-11-15Approval statement: The project was found to be in accordance with the ethical principles and the national norms and standards for conducting Medical Research in Iran.

Modified comb-shaped antisense oligonucleotides may secure us against many important viral diseases including AIDS

To inhibit HIV replication and infection, we have designed novel linear single stranded modified antisense nucleic acid oligonucleotides ending with or without chain terminating bases (Which resemble the shape of the comb). They were targeting specifically the HIV-1 clone pNL4-3 strong promoter pre PBS region to stop cDNA synthesis within or before the R region, preventing the viral reverse transcriptase (RT) jumping to the 3' end and continue copying the virus. The main advantages of our comb shaped oligonucleotides are their specificity and extreme protection against resistance by known viral mutations. Promising results were obtained for two 15-mer compounds at one tenth azidothymidine concentration. As a result we claim that when adapted properly, the comb shaped antivirals can be used to target the genomic RNA of a number of serious viruses such as for example Ebola, SARS-CoV-2, Influenza, Dengue, hepatitis C, Chikungunya and Zika as they are all using polymerases to copy their genomic RNA1-8. Their genomic RNA could be destroyed through the human or viral endonucleases instead of the viral RT RNAseH site when their polymerases are stopped at specific sites.

Diverse and rapidly evolving viral strategies modulate arthropod vector gene expression

Vector-borne viral diseases threaten human and wildlife worldwide. Vectors are often viewed as a passive syringe injecting the virus, however to survive, replicate and spread, viruses must manipulate vector biology. While most vector-borne viral research focuses on vectors transmitting a single virus, in reality vectors often carry diverse viruses. Yet how viruses affect the vectors remains poorly understood. Here we focused on the varroa mite, an emergent parasite that vectors over 20 honey bee viruses, and has been responsible for colony collapses worldwide, as well as changes in global viral populations. Co-evolution of the varroa and the viral community makes it possible to investigate whether viruses affect vector gene expression, and whether these interactions affect viral epidemiology. Using a large set of available varroa transcriptomes we identified how abundances of individual viruses affect the vector transcriptional network. Perhaps surprisingly, we found no evidence of competition between viruses, but rather that some virus abundances are positively correlated. Furthermore, we found a strong correlation between the extent to which a virus interacts with the vector gene expression and co-occurrence with other viruses, suggesting that interactions with the vector affect epidemiology. We experimentally validated this observation by silencing candidate genes using RNAi and found that reduction in varroa gene expression was accompanied by a change in viral load. Combined, the meta-transcriptomic analysis and experimental results shed light on the mechanism by which viruses interact with each other and with their vector to shape the disease course.

INCIDENCE OF TBRV AND ArMV VIRUSES IN NEW CHERRY PLANTATIONS FROM AREA OF ROMANIA

Viral diseases can influence negatively a good evolution of cherry plantations. Two of the viral diseases that attack this species are caused by the ArMV virus, which spreads by multiplying the infected propagating material, by seed and nematodes, and by the TBRV virus, which spreads by multiplying the infected material and nematodes. In order to study the incidence of the two viruses, 10 cherry plantations located in the south of the country were evaluated, in the district of Argeș, Dolj, Ialomița, Ilfov, Călărași, Dâmbovița, Buzău. The planting material used to set up the plantations was both from Romania and from an external source: the Netherlands, Greece, Italy. Viral evaluation performed visually and serologically by DAS-ELISA technique, identified viral infections in 2 of the 10 plantations. In one plantation, TBRV was identified in 20% of the tested samples and in the second, ArMV viruses were identified in 20% of the samples and TBRV in 5% of the samples.