Potato virus Y (PVY)

Non-enveloped, flexuous, filamentous,of 720-850 nm long and 12-15 nm in diameter. Symmetry helical. PVY maybe transmitted to potato plants through grafting, plant sap inoculation and through aphid transmission. Presence of characteristic inclusion bodies within infected plant cells.

1. Dr. Pawan Kumar Kanaujia Assistant Professor Molecular Virology (Theory) Potato Virus Y

2. Potato Virus Y- Symptoms Symptoms Mosaic. Necrosis. Leaf drop streaking. Plant Stunting. Bunching or twisting of leaves

3. Transmitted by aphid Transmitted by grafting Transmission Aphid ( Aphis gossypii ), grafting and sap inoculation

4. Potato virus Y Virus classification (unranked): Virus Class: Stelpaviricetes Order: Patatavirales Family: Potyviridae Genus: Potyvirus Species: Potato virus Y

5. Structure Non-enveloped, flexuous, filamentous, of 720-850 nm long and 12-15 nm in diameter. Symmetry helical. PVY  maybe  transmitted  to  potato  plants  through  grafting, plant sap inoculation and  through  aphid  transmission. Presence of characteristic inclusion bodies within infected plant cells.

6. Monopartite , linear,  ssRNA (+) genome of 10 kb in size 3' terminus has a poly (A) tract 5' terminus has a genome-linked protein ( VPg ) This RNA is enclosed in a protein capsid (CP) composed of up to 2000 subunits of 30–37  kDa

7. GENE EXPRESSION The virion RNA is infectious and serves as both the genome and viral messenger RNA. The genomic RNA is translated into polyproteins which are subsequently processed by the action of three viral-encoded proteinases into functional products. P3N-PIPO is expressed by polymerase slippage mechanism from the P3 ORF and probably acts as a movement protein.

8. The viral RNA encodes a single, large polyprotein that is cleaved by three virus-encoded proteases (P1, helper component proteinase , and the nuclear inclusion body A proteinase ) into ten functional proteins (P1, HC-Pro, P3, 6 K1, CI, 6 K2, VPg , NIa -Pro, NIb , and CP) and additional peptide P3N-PIPO (Fig. ) Potato Virus Y Genetic Variability: A Review Rakesh Kumar Verma , Ritesh Mishra , and Rajarshi Kumar Gaur*Department of Biosciences, College of Arts, Science and Commerce , Mody University of Science and Technology , Lakshmangarh , Sikar 332311 , Rajasthan , India e-mail: [email protected]

9. REPLICATION CYTOPLASMIC Virus penetrates into the host cell. Uncoating , and release of the viral genomic RNA into the cytoplasm. The viral RNA is translated to produce a polyprotein which is processed by viral proteases into the RdRp protein and structural proteins. Replication takes place in  cytoplasmic viral factories. A dsRNA genome is synthesized from the genomic ssRNA (+). The dsRNA genome is transcribed/replicated thereby providing viral mRNAs/new ssRNA (+) genomes. Virus assembly in the cytoplasm. Viral movement protein P3N-PIPO probably mediates virion cell-to-cell transfer.

10. Potato Virus Y life cycle

11. Potato virus Y: biodiversity, pathogenicity , epidemiology and management  pp 1-19|  Cite as General Characteristics of  Potato virus Y  (PVY) and Its Impact on Potato Production: An Overview

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