Biological and molecular characteristics of potato virus X naturally infected potato plants

الملخص EN

Potato viruses were beenidentified in several countriesaround the world included Egypt.

Potato virus X (PVX), is one of the common viruses infecting.

potato crops.

In the current study PVX isolated from naturally mixed viruses and identified based on biological characters; serologically and molecularly.

The incidence of, PVY, PVX, PLRV, AMV, TYLCV were found single and mixing infection with 33.3, 37.1, 12.38, 12.38, 5.12 % frequency respectively out of 105 natural infected potato plants cv.

Sponta.

PVX was detected by distinct symptoms (severe mosaic, yellow blotch ) and DAS-ELISA.

It was isolated on Chenopodium.

amaranticolor and Datora.

stramonium L .

It had wide host range, transmitted mechanically by syringe injection and Grafted tuber, .

The virus particles rod with length wide (475) nm and (12) nm.

The virus stability was TIPexpected at 80⁰C for 10 min.

DEP expected at 10^-8 and  LIVexpected at 7days.

It was formed amorphous and crystal inclusion bodies in epidermal cells.

 PVX have antigenicity character that serological precipitation reactionwith DAS-ELISA.

PVXinfectivityrevealed that 90% , disease severity 85% and high concentration in infected potato plants.

The partial nucleotide sequence of CP gene was about 433 bp.

The genetic distance with other recommended PVX strains registered in GenBank with 10 bar.

The similarity values were recorded 100% with GU384726 1, 97.92 % with Accession no.

MK587495, MF662526, KR605392, KR605379, KR605360 and 98.30% similarity with strain no.

KJ631111.

.

The predict numbers 144 amino acids were starting with Tyrosine.

The genetic distance with other recommended PVX strains registered in GenBank with 0.20 bar It was recorded in gene bank with accession number MW 650651