The potato (Solanum tuberosum) is the fourth most widely grown crop around the globe. It is
used to make a variety of food products all over the world, including chips, crisps, potato flour,
vegetable salad, canned food, and livestock supply. Unfortunately, a variety of abiotic and
biotic stresses, such as soft rot pathogens, affect potato tuber yield and quality (Pectobacterium
and Dickeya). Soft rot is most common throughout field production and storage. Our research
study was aiming to analyse peroxidase and polyphenol oxidase, catalase, and phenol
production in the infected potato Sponta and Mondial cultivars with Pectobacterium spp in
response to 5 mM of glycyrrhizic acid ammonium salt, salicylic acid, and composites in the
normal and nanoform treatments. The obtained results showed that Peroxidasee activities in
potato leaves increased to the highest level of 3.9 U.ml-1 in Mondial cultivar in response to 5
mM SA NPs compared to 0.73 U.ml-1 in the positive control and 0.47 U.ml-1 in the negative
control. While Sponta cultivar scored 3.53 U.ml-1 of peroxidase activities in response to 5 mM
SA NPs in comparison with 0.57 U.ml-1 and 0.33 U.ml-1 in the positive and negative control
respectively. Also, Peroxidase activities in potato tubers boosted to the highest level of 3.9
U.ml-1 in Mondial cultivar in response to 5 mM SA NPs and 5mM nanocomposites (Ch NPs+
SA NPs + GSA NPs) compared to 0.6 U.ml-1 in the positive control and 0.5 U.ml-1 in the
negative control. Treated Mondial cultivar showed the highest polyphenol oxidase activities in
the potato leaves at 0.95 U.ml-1 in response to 5 mM SA NPs followed by 0.923 U.ml-1 and
0.813 in response to 5 mM nanocomposites (Ch NPs+ SA NPs + GSA NPs) and 5 mM GSA
NPs treatments respectively, compared to 0.15 U.ml-1 in the positive control and 0.343 U.ml-1
in the negative control. However, Sponta cultivar showed polyphenol oxidase activities in
potato leaves 0.937 U.ml-1, 0.86 U.ml-1, 0.757 U.ml-1 and 0.72 U.ml-1 in response to 5 mM SA
NPs, 5 mM nanocomposites (Ch NPs+ SA NPs + GSA NPs), SA and GSA NPs treatments
respectively in comparison with 0.137 U.ml-1 in the positive control and 0.333 U.ml-1 in the
negative control. Treated Mondial and Sponta cultivars with 5 mM SA NPs scored the highest