Cloning of the Terminal Regions of Apple stem pitting virus in Pear Trees Using 3‘ and 5‘ RACE Prokaryotic expression of Apple stem pitting viruscoat protein and antiserum preparation Development of a TaqMan Real-time RT-PCR Method for Detecting Apple stem pitting virus(ASPV) Cloning of the Terminal Regions of Apple stem pitting virus in Pear Trees Using 3‘ and 5‘ RACE RT-PCR Detection and Molecular Variability of Apple stem pitting virus Multiplex RT-PCR Assay for Simultaneous Detection of Three Latent Apple Viruses