Insecticidal potential of Eucalyptus cinerea essential oil and its major constituent 1,8-cineole against Ectomyelois ceratoniae Zeller and Ephestia kuehniella Zeller (Pyralidae).

The aim of this study was to investigate the insecticidal properties of essential oil derived from Eucalyptus cinerea leaves and its main component, 1,8-cineole, against two significant pests of stored dates, Ectomyelois ceratoniae and Ephestia kuehniella (Pyralidae). The impact of the treatment on the sensory characteristics of date fruits was assessed to verify the complete absence of off-odours and off-flavours. Gas chromatography - mass spectrometry analysis of E. cinerea essential oil revealed that the primary compound was 1,8-cineole (74.5%). Fumigant toxicity of the two pests, indicated that first instar larvae (L1) exhibited greater tolerance to E. cinerea EO and 1,8-cineole than L5, while adult forms were more susceptible than larvae. The E. cinerea EO had a noticeable pest contact activity when used at a concentration of 0.35 µL/cm2 caused 100 and 88.3% mortality to E. ceratoniae and E. kueheniella, respectively, after 1 hour of exposure. Hedonic evaluation showed that consumers' appreciation of fumigated dates was not significantly different to the no treated dates.

Insights for the control of dried-fruit beetle Carpophilus hemipterus (Nitidulidae) using rosemary essential oil loaded in chitosan nanoparticles.

Natural insecticidal products, essentially essential oils and their bioactive compounds are available as an excellent alternative method to control insect pests as well as they are less toxic to human health. However, due to their volatile constituents, encapsulation could be considered as the most suitable solution for their practical application. Therefore, this study aims to explore the insecticidal toxicity of chitosan nanoparticles loaded with Rosmarinus officinalis essential oil against adults of Carpophilus hemipterus. Chitosan nanoparticles were prepared by ionic gelation method with an encapsulation efficiency 41.543.1% and loading capacity 5.24G0.28%. Results revealed that chitosan nanoparticles loaded rosemary oil exhibited interesting insecticidal toxicity towards C. hemipterus adults in stored dates with 50.73% mortality. Overall, this work pointed out that the innovative design method based on chitosan-nanoparticles loaded rosemary oil can be promoted in integrated pest management program for stored date pests.

Laurel essential oil: biological activities and application for semolina preservation against the red flour beetle Tribolium castaneum (Tenebrionidae).

The phytochemical composition of Laurus nobilis essential oil and their anticholinesterase, antioxidant, and insecticidal potential were studied. Also, the oil volatile fraction was compared in semolina at the beginning and after storage periods. For that, a headspace solid-phase-microextraction analysis (HS-SPME) coupled with gas chromatography and mass spectrometry was undertaken. Significant quantitative and qualitative differences of the oil volatile fraction were detected according to storage periods and occupation space ratios. Additionally, anti-acetylcholinesterase activity of L. nobilis oil against T. castaneum adults was evaluated. Results revealed that insecticide activity varied according to storage duration and occupation space. Besides, the oil acts on acetylcholine hydrolysis by inhibiting the activity of acetylcholinesterase. These results highlighted that L. nobilis essential oil may be recommended as an eco-friendly alternative for preserving semolina during storage.

Screening for insecticidal toxicity of Urginea maritima (L.) bulbs and Asphodelus microcarpus (L.) tubers for the control of Tribolium castaneum (Tenebrionidae).

This research was conducted to determine the effect of geographical distribution on morphological characteristics of plants and some chemical compounds such as polyphenols. Moreover, we explore the contact toxicity of ethanolic and methanolic extracts from Urginea maritima bulbs and Asphodelus microcarpus tubers collected from three localities in the North West of Tunisia against Tribolium castaneum adults. The toxicity results demonstrated that both of the studied plant extracts had an effective control against T. castaneum at concentration 7.5 µL/L air, thus total mortality reached. In addition, results showed plant extracts with methanol exhibited high mortality percentage of T. castaneum. On the other hand, results revealed that chemical composition of U. maritime bulbs and A. microcarpus tuber extract depends on the soil components and geographical distribution of plants. The present investigation confirmed that A. microcarpus and U. maritima may be recommended as an eco-friendly alternative to synthetic insecticide against T. castaneum.

Fumigant toxicity of four essential oils against the carob moth Ectomyelois ceratoniae Zeller and the Mediterranean flour moth Ephestia kuehniella.

Eucalyptus leucoxylon, Rosmarinus officinalis, berries, and leaves of Schinus molle essential oils were analysed using GC-MS techniques and assessed for their fumigant toxicity against adults, larvae, and eggs of Ectomyelois ceratoniae and Ephestia kuehniella. Results showed that E. leucoxylon contained Spathulenol, p-Cymene, and Cryptone as major compounds. GC - MS analyses showed that the major compounds of R. officinalis essential oil were 1,8-Cineole, Camphor, and α-pinene. I-Phellandrene, t-Muurolol, and Phellandrene were the major components of the S. molle leaves; while I-Phellandrene, Limonen, and δ-Cadinene were the major components of the S. molle berries. S. molle berries were the most efficient followed by R. officinalis against E. ceratoniae and E. kuehniella. The most effective tested essential oil against E. ceratoniae larvae was S. molle berries. Results on the ovicidal and larvicidal effects of the tested oils demonstrated that R. officinalis was the most effective essential oil against E. kuehniella eggs.