Paper Title
In Vitro Study of the Biopesticide Effect of Rosemary Extracts on Pseudomonas Strains Responsible of Tomato Diseases

It is necessary to use pesticides: fungicidal insecticides, herbicides in intense production systems. However, the use of these agricultural inputs has led to contamination of all. Components of the environment on the one hand, and an increase in the resistance of pathogens responsible for certain serious crop diseases, on the other hand. Today Natural substances from plants offer an alternative to chemical control in the agricultural field. These biocontrol products are very important and very reassuring for human health and the preservation of nature. Among plant species rich in natural substances and in polyphenols and which require chemical and biological decryption, Rosmarinus officinalis. In this context, a study was therefore undertaken on the biopesticidal activity of its aqueous and methanolic extracts. To do this, a phytochemical screening revealed the different major metabolites in the leaves. The total polyphenols were extracted by the method of Folin-Ciocalteu (FC) and their antibacterial activities were evaluated in vitro according to the diffusion technique on solid medium and the activity in liquid medium (batch culture) for Pseudomonas sp 3. Comparative tests with synthetic products were also included in the tests. The evaluation of the pesticidal power of the polyphenolic compounds shows a strong inhibition power on certain strains. This inhibition depends on the nature of the bacterial agent; it appears to be more pronounced for Pseudomonas sp. Key words: Biopesticide effect, Pseudomonas, Rosemary, tomato diseases