Tunisian populations of Culex pipiens pipiens, an important vector of human diseases, have developed resistance to organophosphate insecticides. To understand the origin of this resistance, knowledge of the impact on agricultural pest and mosquito control activities and its significance for the resistance mechanisms will be required. Five populations of C. p. pipiens were collected at various sites with different agricultural pest and mosquito control activities throughout Tunisia and tested for fenitrothion resistance level. Results were compared to those obtained from a control population where no chemical activities have been carried out. Our results strongly suggest the presence of a correlation between agrochemical products and the recorded resistance despite a rather limited number of studied sites (five populations). On the other hand, organophosphates control activities let us suggest the existence of an important impact on fenitrothion resistance. However, it appears that the application of pyrethroids have little to no impact on fenitrothion (organophosphate) resistance. The recorded resistance of the control population should be due to anthropogenic factors; however, the combined effect of migration and gene flow on the evolution of insecticide resistance should also be taken into consideration. The recorded resistance was mediated by both enzymatic detoxification and target-site sensitivity. Our findings showed a positive correlation between both metabolic and target site resistance and the level of resistance. In conclusions, we can say that the use of pesticides and insecticides by both agricultural and public health departments in Tunisia should be more rationalized to reduce the development of resistance in C. p. pipiens populations.

The European wheat stem sawfly, Cephus pygmeus (Linnaeus, 1767) and the black grain stem sawfly, Trachelus tabidus (Fabricius, 1775) are important and common pests in wheat growing areas of Turkey. These sawfly species continue to be a threat to wheat production in the southeast Anatolia Region of the country. This study was conducted to determine larval infestation rates and yield losses caused by these sawfly species in common wheat cultivars grown in the southeast Anatolia Region. Durum and bread wheat fields were surveyed to record larval infestation and damage caused by these sawfly species in four provinces (Adıyaman, Diyarbakır, Mardin and Şanlıurfa) of the region. A total 100 wheat fields were randomly selected and stem samples were taken from each field during the harvest period. Spike length, mean number of grains, grain weight and 1000-grain weight were recorded from 100 infested and healthy spikes and crop losses were calculated for 16 wheat cultivars.

The surveyed provinces significantly differed in infestation rates, with the highest infestation level recorded for Diyarbakır province with a mean of 17.4% (range 2.1- 54.3%), while the minimum infestation was determined in Adıyaman province with a mean of 5.3% (range 1.4-17.3%). Durum and bread wheat cultivars had negligible effects on larval infestation. Spike length of infested wheat plants was reduced by 0.9-14.4% and the mean number of grains and grain weight were reduced by 0.5-19.7% and 7.2-28.5%, respectively. The loss in 1000-grain weight was 8.9% in bread wheat cultivars, while the loss was 7.9% in durum wheat cultivars. It was concluded that the loss in 1000-grain weight reached 10.9%. Therefore, appropriate control measures should be taken against stem sawflies in high-infestation locations.

Anomala corpulenta is an insect pest that is widely distributed in China, and it can cause large economic losses in agriculture, horticulture, and forestry. It is difficult to control because most of the lifecycle is underground. Trapping adults would be an environmentally sustainable way to reduce damage caused by this insect. Odorant-binding proteins (OBPs) and chemosensory proteins (CSPs) are considered to be important chemodetection proteins. In this study, we investigate the expression of odorant-binding protein genes and chemosensory protein genes in different tissues of the adult and other developmental stages. The antenna had the highest expression levels for OBPs and CSPs of all tissues, except for OBP7 which was most highly expressed in the head without antenna. Besides the antenna, the head without antenna had the next highest expression levels for all OBP and CSP genes. The expression of OBP2, OBP3, OBP14, and CSP in the adult was higher than in other stages, while, OBP7 was lower than in other stages. Before estimating the expression of OBPs and CSPs, seven candidate reference genes were tested for stability among the tissues of adult and other development stages. GAPDH was the best reference gene in different tissues of the adult, and RPL13a was the best reference gene in different development stages. Our results provide a foundation for further research on the molecular aspects of chemical communication of this insect.

In this research, the effects of essential oils isolated from four ecotypes of cumin (Cuminum cyminum L.) Northern-Khorasan (NS), Fars (FS), Kerman (KK), and Kerman (KR) were evaluated on the 4^th instar larvae of pink stem borer, Sesamia cretica Lederer. The essential oils were extracted from seeds and the chemical composition was assessed via Gas Chromatography-Mass Spectrometry (GC-MS). Cuminaldehyde (43.599-55.939%), γ-terpinene (13.134-21.750%), m-cymene (8.349-16.935%), ß-pinene (6.320-14.130%), and α-phellandrene (2.137-4.742%) were the main components of the essential oils. Four types of blood cells: prohaemocytes, plasmatocyte, granulocyte, and oenocytoid were identified in the haemolymph of the 4^th instar larvae of S. cretica. The decreasing haemocyte counts were found to be significant in the different ecotypes of C. cyminum essential oil. The utilized concentrations and specified times had significant effects on the reductions of the mentioned cell numbers. The fewest number of cells for all ecotypes was measured after 48 h. The highest decline in the total haemocyte count was related to the concentration of 8000 ppm in NS ecotype. The lowest LC50 value was observed in KR ecotype. Based on the results of the present study, the essential oils isolated from the different ecotypes of C. cyminum showed to be promising candidates for S. cretica management.

Despite the tenebrionid genus Blapstinus being species rich with 91 described species in North America, individual beetles are not commonly observed. We collected Blapstinus metallicus (Fab.) in Maine wild blueberry fields in 2012 and in a Massachusetts wooded residential property in 2017. This species has the largest geographic range of all the Blapstinus species reported in North America. Our paper reports on the death feigning behavior of B. metallicus and provides a review of the literature on this little studied group of beetles.

There are several species of spiders in the midwestern United States that cohabit with humans, but probably the most concerning is the brown recluse spider, Loxosceles reclusa, (Araneae: Sicariidae) because of the potential for a venomous bite. Thus, managing the brown recluse spider is a continuous endeavor. Essential oils (EOs), i.e. specific plant extracts, have often been used to control or deter other arthropods and pests. In this study, several EOs were selected to test their effectiveness as alternatives to synthetic pesticides for L. reclusa control. Spiders were exposed to EOs by direct contact or as a fumigant (inhalation) treatment for 24 h, and mortality was recorded. Physical contact with the oils resulted in the greatest mortality, with wintergreen, peppermint and lavender to a lesser extent, showing potential for L. reclusa control. Mortality attributed to lemon, lemongrass or wild orange was too low to provide effective reduction of L. reclusa populations. Fumigants (inhalation) caused less mortality than contact treatments, never resulting in more than 20%. Two EOs, wintergreen and peppermint, demonstrated effective toxicity to L. reclusa and may have potential as alternatives to synthetic pesticides for this pest, warranting further investigation.

Laboratory experiments were conducted to determine larval movement of the spotted wing drosophila (Drosophila suzukii Matsumura). Movement of larvae outside of the wild blueberry fruit (Vaccinium angustifolium Aiton) can occur after exhausting fruit food resources pri- or to completion of development or just prior to pupation. We found that when provided a choice larvae select moist compared to dry environments both in plastic arenas providing only filter paper for shelter and in a soil filled petri dishes. Movement was usually limited to less than 7.5 cm in the soil from a release point. An exponential decay model suggests that only 0.1% of a larval population will move as far as 17.5 cm. Results of our study suggest that while larvae move readily, they have minimal ability to avoid localized xeric soil micro-climatic conditions through movement. However, they will select less stressful moist soil environments.