Some Additional Viral Diseases of Temperate Fruit Trees in India

Five virus diseases viz. apple rough skin, apple tumour, peach gummosis, apricot severe mosaic and Paja rosette of temperate fruit trees prevalent in Himachal Pradesh are described. All diseases are only graft transmissible. Apple rough skin and peach gummosis are widely prevalent and most destructive in nature than others. Peach gummosis virus infects some Prunus species. Cross-protection tests suggests that apricot mild spot mottle and apricot severe mosaic may be closely related strains of the same virus. A disease resembling apple tumour virus in symptomatology has not been reported elsewhere. Paja, Prunus puddum rosette resembles in symptoma-lology with peach rosette which is now believed to be caused due to mycoplasma.