Carol Samaan^1*, Ibrahim Alabid¹, Samir Tabbache¹ and Jafargholi   Imani²

1 Department of Plant Protection, Faculty of Agricultural Engineering, University of Lattakia, Syria.
2 Institute of Plant Pathology, Faculty of Agricultural Sciences, Justus Liebig Giessen University, Germany.
(*Corresponding author: Carol Samaan, Email: carol95samaan@gmail.com ).

Received: 19/ 5/ 2025     Accepted: 19/ 10/ 2026

Abstract

This research was conducted to study the effect of in vitro garlic extract and commercial garlic extract VEG’LYS in the bacterium Pseudomonas syringae pv. tomato caused by the bacterial speck disease on tomato plants in vitro conditions. The inhibitory effect of the extract was tested by measuring the inhibition distance around the paper disc treated with the extract. The results showed that the garlic extract prepared from the garlic plant in the laboratory and the commercial garlic extract showed an inhibitory effect on the growth of bacteria in vitro at different concentrations (1,5,10,15,20,25)%.Where the lowest rate of inhibition was reached for laboratory-prepared garlic was 10% at a concentration of 1% of the extract and for the extract of commercial garlic preparation 50.77%, While the 25% concentration gave the highest inhibition rate of 27.56% for laboratory-prepared garlic and 75.56% for commercial garlic extract. while the concentration of 25% gave an inhibition rate of 27.56% for the laboratory prepared garlic and 75.56% for the commercial garlic extract. The inhibition ratios for the control (distilled water), in the antibiotic tetracycline and at the pesticide copper oxychloride were 0%, 36.67% and 14.44% respectively. The results of this research showed that laboratory garlic plant extract and commercial garlic extracts can play an important role in controlling bacterial speck disease on tomatoes.

Keywords: tomato, Pseudomonas syringae pv. tomato, extract, Allium sativum.

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