الفهرس 
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Abstract
1. Introduction
Potato (Solanum tuberosum ssp. tuberosum L.) is the fourth most important food crop worldwide after wheat, maize and rice (Hawkes, 1990). Egypt also ranks among the worlds top potato exporters. In 2021 annual output rose 1.9 million metric tons (Mt) . During which Egypt imported about 135 thousand tons of seeds., The cultivated area reached 375,000 feddans in 2021 from 475,000 feddans in 2020 (FAOSTAT, 2021) therefore, making Egypt Africa‘s No. 1 potato producers. As a clonally propagated crop, potato is vulnerable to pests and diseases affecting leaves, stems, roots, and tubers. Infected seed tubers transmit pathogens to the next growing season, thereby causing progressive degeneration of yield (Agrios, 1997). The commonly cultivated potato (Solanum tuberosum) is a heterozygous autotetraploid (2n=4x=48) having 48 chromosomes and 4 genome complements (Hawkes, 1994). A complement of the potato genome consists of 12 chromosomes having 1 x 109 bp of DNA (Ganal et al., 1990). One of the principal threats to p