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Abstract Members of the eukaryotic translation initiation complex are co-opted in viral infection, leading to susceptibility in many crop species, including stone fruit trees (Prunus spp.). Therefore, modification of one of those eukaryotic translation initiation factors or changes in their gene expression may result in resistance. We searched the crop and wild Prunus germplasm from the Armeniaca and Amygdalus taxonomic sections for allelic variants in the eIF4E and eIFiso4E genes, to identify alleles potentially linked to resistance to Plum pox virus (PPV). Over one thousand stone fruit accessions (1397) were screened for variation in eIF4E and eIFiso4E transcript sequences which are in single copy within the diploid Prunus genome. We identified new alleles for both genes differing from haplotypes associated with PPV susceptible accessions. Overall, analyses showed that eIFiso4E is genetically more constrained since it displayed less polymorphism than eIF4E. We also demonstrated more variations at both loci in the related wild species than in crop species. As the eIFiso4E translation initiation factor was identified as indispensable for PPV infection, a selection of ten different eIFiso4E haplotypes along 13 accessions were tested by infection with PPV and eight of them displayed a range of reduced susceptibility to resistance, indicating new potential sources of resistance to sharka.

Natural products play an important role in the production and development of food and medicine. In olive tree cultivation and olive processing industry, vast amounts of by-products are yielded. Olive leaves constitute the major by-product of olive industry. Olive leaf is potential source of phenolic compounds. Plant polyphenols have attracted great interest due to their antimicrobial activities. It was aimed to isolate the oleuropein compound from olive leaf and to identify its antimicrobial effects in this research. In the first stage, methanol extract was obtained from the olive leaf. After then, ethyl acetate extract (including oleuropein with 93.5% purity) procured from methanol extract. Ethyl acetate extract was subjected to chromatographic technique to obtain oleuropein in high purity (97.6%). The structure of oleuropein was determined by spectroscopic method including 1H and 13C NMR besides comparing isolated oleuropein with the standard commercially obtained. Antimicrobial activity of methanol extract, ethyl acetate extract and oleuropein was investigated on Bacillus subtilis, Candida tropicalis, Lactobacillus brevis, Lactobacillus plantarum, Proteus vulgaris, Saccharomyces cerevisiae, Salmonella enteritidis microorganisms by 96-well microtiter plate method. It was determined that MIC (Minimum Inhibitory Concentration) values of olive leaf products ranged between 1:1 (50 mg/mL) and 1:8 (6.25 mg/mL) for tested microorganisms. [ABSTRACT FROM AUTHOR]