Essential Oils as Biocides for the Control of Fungal Infections and Devastating Pest (Tuta absoluta) of Tomato (Lycopersicon esculentum Mill.)

Abstract

Thymus capitatus and Tetraclinis articulata essential oils as well their major components (carvacrol and α-pinene) were evaluated for their antifungal and insecticidal activities. Both oils showed good in vitro antifungal activity against Fusarium oxysporum, Aspergillus niger, Penicillium sp., Alternaria alternata, and Botrytis cinerea, the fungi causing tomato rot. In vivo results indicate the efficacies of both essential oils and carvacrol of reduce postharvest fungal pathogens, such as B. cinerea and Al. alternata that are responsible of black and gray rot of tomato fruit. Disease incidence of Al. alternata and B. cinerea decreased on average from 55% to 80% with essential oil of Th. capitatus and pure carcvacrol, while Te. articulata essential oil exhibited inhibition of fungal growth of 55% and 25% against Al. alternata and B. cinerea, respectively, with concentration of 0.4 μl/l air. The insecticidal activity of Th. capitatus and Te. articulata essential oils exhibited also a good insecticidal activity. At the concentration of 0.2 μl/ml air, the oils caused mortality over 80% for all larval stages of Tuta absoluta and 100% mortality for the first-instar after 1.5 h only of exposure. α-Pinene presented lower insecticidal and antifungal activities compared to essential oils of Th. capitatus, Te. articulata and pure carvacrol. Thus, these essential oils can be used as a potential source to develop control agents to manage some of the main pests and fungal diseases of tomato crops.

Chemical Variability and Chemotype Concept of Essential Oils from Algerian Wild Plants

“…Their antimicrobial activity increases the shelf life of foods [6]. Some essential oils are antifungal agents useful for food preservation [7][8][9][10][11][12][13][14][15][16]. In addition, these volatile molecules are used in agriculture as soil correctors (redox couple) due to their targeted action and biodegradable nature [17,18].…”

Essential Oils from Two Apiaceae Species as Potential Agents in Organic Crops Protection

“…Today, it is widely recognized that herbicides may pose a significant risk to human health and to the environment. This risk has led to an increased interest in alternative strategies which have led to the development of biodegradable compounds [1,2]. Aromatic plants are increasingly used for pest control in bioagriculture.…”

“…In our characterization of Algerian aromatic plants in the field of crop protection [1,[3][4][5]7,12,29,30], we reported here the chemical composition of the essential oils of E. triquetrum and S. olusatrum from western Algeria using a combination of flash chromatography followed by capillary GC(RI) and GC/MS. Biological activities were established through the characterization of phytotoxicity assays (germination, thylakoid activity and growth assay on the model grass watercress (Lepidium sativum)), ecotoxicology tests against Artemia larvae (A. salina) and freshwater snail (B. glabrata), antibacterial activity against potato blackleg disease (Pectobacterium atrosepticum) and Gram-negative soil bacterium (Pseudomonas cichorii) and finally antifungal activity against noble rot fungus (Botrytis cinerea) IP 1854.89 and wheat head blight fungus (Fusarium graminearum).…”