The Valorization of Spent Coffee Grounds Extract as A Prospective Insecticidal Agent Against Some Main Key Pests of Phesolus Vulgaris in Laboratory and Field

Exploiting massive amounts of food and agro-waste represents a severe social, economic, and environmental issue. Under the growing demand toward food products free of toxic synthetic insecticides, the methanolic extract of spent coffee grounds (SCGs), which represent the main by-product of coffee production, was applied in the current study as a bioinsecticide against the main pests of the green bean; Spodoptera littoralis, Agrotis ipsilon, Bemisia tabaci, Empoasca fabi and Aphis craccivora. Deterrent assay, contact bioassay, and lethal concentration analysis were performed to reveal the repellent, antifeedant, and oviposition deterrent effects. Parallel to the above-performed bioassays, the phytochemical composition of the SCGs methanolic extract was investigated via High-Performance Liquid Chromatography (HPLC) analysis. Fourteen phenolic acids and five flavonoids in addition to caffeine (alkaloid) have been identified in the extract. Cinnamic, rosmarinic, and gallic acids were the predominant phenolics, while apigenin-7-glucoside was the main flavonoid, followed by naringin, catechin, and epicatechin. The extract of SCGs showed an insecticidal effect, with mortality between 27.5-76% compared to the control (7.4%) and based on the concentration of the extract used. In the same trend, oviposition efficiency revealed different laid egg batches (0.67, 2.33, 7.33, and 8.67 batch/jar) for 100, 50, 25% of the SCGs extract and control. Finally, the major components of SCGs extract were docked into insecticide acetylcholinesterase enzyme to explore their potential of inhibition, where apigenin-7-glucoside showed a higher binding affinity, followed by catechin, compared to the control (lannate). Obtained findings could be a starting point to develop novel bioinsecticides from SCGs.

Metarhizium anisopliae blastospores are highly virulent to adult Aedes aegypti, an important arbovirus vector

Background The use of entomopathogenic fungi (EPF) for the control of adult mosquitoes is a promising alternative to synthetic insecticides. Previous studies have only evaluated conidiospores against adult mosquitoes. However, blastospores, which are highly virulent against mosquito larvae and pupae, could also be effective against adults. Methods Metarhizium anisopliae (ESALQ 818 and LEF 2000) blastospores and conidia were first tested against adult Aedes aegypti by spraying insects with spore suspensions. Blastospores were then tested using an indirect contact bioassay, exposing mosquitoes to fungus-impregnated cloths. Virulence when using blastospores suspended in 20% sunflower oil was also investigated. Results Female mosquitoes sprayed with blastospores or conidia at a concentration of 108 propagules ml−1 were highly susceptible to both types of spores, resulting in 100% mortality within 7 days. However, significant differences in virulence of the isolates and propagules became apparent at 107 spores ml−1, with ESALQ 818 blastospores being more virulent than LEF 2000 blastospores. ESALQ 818 blastospores were highly virulent when mosquitoes were exposed to black cotton cloths impregnated with blastospores shortly after preparing the suspensions, but virulence declined rapidly 12 h post-application. The addition of vegetable oil to blastospores helped maintain virulence for up to 48 h. Conclusion The results showed that blastospores were more virulent to adult female Ae. aegypti than conidia when sprayed onto the insects or applied to black cloths. Vegetable oil helped maintain blastospore virulence. The results show that blastospores have potential for use in integrated vector management, although new formulations and drying techniques need to be investigated. Graphical abstract

Residual and Fumigant Effects of Bendiocarb WP80 in a Malarious Areas in Borderline of Iran and Pakistan

Background: Malaria and leishmaniasis are the public health problems in southern Iran. The main activity of vector control is indoor residual spraying using pyrethrpids. The aim of study was to evaluate the biological assays of bendiocarb WP at different surfaces of wall. Materials and Methods: The residual effect of bendicocarb WP80 at 400 mg/m2 was evauated on various local surfaces of rooms such as mud and plaster as well as thatch roofs and wooden. WHO standard cones using contact bioassays were carried out using laboratory reared sugar-fed, 48-72 h old females of Anopheles stephensi . Contact bioassays were carried out on sprayed surfaces for 150 days.Results: Contact bioassay on surfaces treated with bendicocarb WP80 diffferent surfaces was estimated about 2 months. Fumigant tests of bendicocarb WP80 at 400 mg/m2 revealed 50-93.83% mortality with one month persistency.Discussion: The rsults hsowed that carbamte insecticide could be used as rotation with pyrethroids for malaria vector control .

SELECTIVITY OF INSECTICIDES TO Encarsia hispida (Hymenoptera: Aphelinidae)

ABSTRACT The use of non-selective insecticides in agricultural production can reduce or eliminate biological agents that regulate insects that are undesirable to humans in production processes. Here, the toxicity of synthetic products on the parasitoid Encarsia hispida was evaluated, the host of which is the whitefly, Bemisia tabaci biotype B, found on cotton plants. The study was carried out using bioassays, in a completely randomized design in a factorial scheme. Pupae and adults of E. hispida were used in the bioassays, which had been sprayed with various chemicals (thiamethoxam, deltamethrin, imidacloprid, and pyriproxyfen) at different concentrations (1.0 g L-1, 1.0 mL L-1, 4.0 mL L-1, and 2.5 mL L-1). The control treatment was distilled water. Chemicals were topically placed in the dorsal region of the tegument of 1 and 3-day old pupae. Then, between 1 and 15-days of emergence of adult parasitoids, residual contact bioassay were used to determine the toxicity of the insecticides. The insecticides thiamethoxam and imidacloprid were harmless to the pupal stage of E. hispida, but were harmful to the adult stage. The insecticides deltamethrin and pyriproxyfen were harmful to both pupal and adult stages of E. hispida.

Repellency, Toxicity, Gene Expression Profiling and In Silico Studies to Explore Insecticidal Potential of Melaleuca alternifolia Essential Oil against Myzus persicae

In the current study, deterrent assay, contact bioassay, lethal concentration (LC) analysis and gene expression analysis were performed to reveal the repellent or insecticidal potential of M. alternifolia oil against M. persicae. M. alternifolia oil demonstrated an excellent deterrence index (0.8) at 2 g/L after 48 h. The oil demonstrated a pronounced contact mortality rate (72%) at a dose of 4 g/L after 24 h. Probit analysis was performed to estimate LC-values of M. alternifolia oil (40%) against M. persicae (LC30 = 0.115 g/L and LC50 = 0.37 g/L respectively) after 24 h. Furthermore, to probe changes in gene expression due to M. alternifolia oil contact in M. persicae, the expression of HSP 60, FPPS I, OSD, TOL and ANT genes were examined at doses of LC30 and LC50. Four out of the five selected genes—OSD, ANT, HSP 60 and FPPS I—showed upregulation at LC50, whereas, TOL gene showed maximum upregulation expression at LC30. Finally, the major components of M. alternifolia oil (terpinen-4-ol) were docked and MD simulated into the related proteins of the selected genes to explore ligand–protein modes of interactions and changes in gene expression. The results show that M. alternifolia oil has remarkable insecticidal and deterrent effects and also has the ability to affect the reproduction and development in M. persicae by binding to proteins.

Selectivity of organic compounds to the egg parasitoid Telenomus remus Nixon (Hymenoptera: Plastygastridae)

The selectivity of insecticides, bio-protective mixtures, and biofertilizers used in organic soybean production was evaluated for adults and pupae of the egg parasitoid Telenomus remus Nixon (Hymenoptera: Platygastridae) under laboratory conditions in accordance with protocols proposed by the International Organization for Biological Control (IOBC). The products sprayed (dosage/180L of water) were: 1) Baculovírus anticarsia 140x109 cpi; 2) Bacillus thuringiensis 16.8g; 3) Azadirachtin-A, azadirachtin-B, nimbina and salamina 9.6 ppm; 4) Rotenoids 4 liters; 5) Nitrogen 1.3%, phosphorus 3.0% and total organic carbon 8.0% 3 liters; 6) Sodium silicate 2% 4 liters; 7) Copper 7% + calcium 3.3% 1.8 liters; 8) Sulfur 20% + quicklime 10% 1.8 liters; 9) Chlorpyrifos 384g (positive control); 10) Distilled H2O (negative control). The results of experiments using pupae indicate that the organic compounds were classified as harmless (Class 1), except for the copper 7% + calcium 3.3% and sulfur 20% + quicklime 10%, which were classified as slightly harmful (Class 2). The contact bioassay with adults showed that all products were classified as harmless (Class 1). Only chlorpyrifos (384g) was classified as harmful (Class 4) for both stages of the parasitoid. However, the use of this product (chlorpyrifos) is not permitted in organic farming, and even in conventional farming is recommended, where feasible, replacement of the product with one compatible with the preservation of T. remus in nature. Thus, the products tested and used in organic soybean production were considered compatible with the parasitoid eggs of T. remus.