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Most recurrently available organic solvents are toxic and inflammable and pose high risks to human health. Natural deep eutectic solvents (NADESs) have been developed as promising green alternatives.We aimed to extract polyphenolic compounds from Mentha pulegium using lactic acid-based deep eutectic solvents. Extraction parameters were optimized by response surface methodology.Combined with ultrasound-assisted extraction, three different lactic acid-based deep eutectic solvents were investigated for the extraction of polyphenols. Methanol (80%, v/v) was used for comparison. The optimized influencing factors were: water content in solvent, extraction time, and temperature. The design was adopted including 17 experiments with three center points.All NADESs tested showed an excellent extraction efficacy compared to 80% methanol. Under the optimized conditions, with 45% of water, at 30°C, and for extraction 90 min, the highest extraction yields were recorded using lactic acid:sodium acetate (3:1), achieving 173.35 ± 0.02 mg gallic acid equivalents (GAE)/g dry weight (dw) of polyphenols and 95 ± 0.09% antioxidant activity. After extraction for 90 min at 80°C with 18% of water, we obtained 164.06 ± 0.01 mg GAE/g dw and 94 ± 0.02% antioxidant activity using lactic acid:glucose (5:1). Efficient recovery (64.92 ± 0.01 mg GAE/g dw and 97 ± 0.1% antioxidant activity) was achieved using lactic acid:glycine (3:1) with 31% of water, at 35°C, and extraction for 30 min.Our results indicate that with optimized parameters, the proposed natural solvents are excellent alternatives to chemical ones for the extraction of phenolic compounds.

The present study characterized and evaluated the antifungal, nematicidal, acaricidal and repellent activities of Ridolfia segetum essential oil (EO), against the fungus Botrytis cinerea Pers., the nematode Meloidogyne javanica and the mite Tetranychus urticae Koch under laboratory conditions. The EO exerted inhibition of the mycelial growth of B. cinerea with median inhibitory concentration (IC50) of 3.63 μL/mL and 0.92 μL/mL air, under contact and vapor phase conditions, respectively. EO application against M. javanica revealed a strong nematostatic effect on second-stage juveniles (J2) and eggs of the root knot nematode with median lethal concentration (LC50) of 10.37 and 9.26 μL/mL, respectively. The oil was toxic to T. urticae by residual contact with median lethal dose (LD50) of 6005 µL/L and exhibited a repellent effect with a repellency index (RI) of 55%. Results suggest that R. segetum oil has potential to be formulated in biopesticides to control the targeted pest and diseases.

Agroecological productivity of the Arganeraie Biosphere Reserve of Morocco is limited by the wide spread and dynamics of plant parasitic nematodes (PPN). Ecological studies of nematode communities are required to develop effective biological management of these bioagressors as conventional control methods of PPN are inadequate and have persistent harmful effects. Fifty-nine organic vegetable soils in Souss-Massa were nematologically sampled, and assessment of taxonomic proliferation was made in relation to host species, geographical origin, and climatic and microclimatic factors. Twenty-four nematode genera were identified as obligate and facultative plant feeders. Taxonomic diversity increased from Chtouka to Taroudant and Tiznit provinces. Soil texture, organic matter, pH, nitrogen, zinc, magnesium, copper, altitude, and humidity and temperature were seen to effect driving roles in the abundance, distribution, and community structures of nematodes. The most prevalent taxa posing a high risk to organic agriculture of Souss Massa were needle nematodes (Longidorus spp.) and root-knot nematodes (Meloidogyne spp.). Edaphic and climatic variables effected nematode populations greatly. A combination of biological treatments and appropriate agroecological practices restricting important economic PPN growth and enhancing soil quality are required to achieve sustainable management in the area.

Agroecological productivity of the Arganeraie Biosphere Reserve of Morocco is limited by the wide spread and dynamics of plant parasitic nematodes (PPN). Ecological studies of nematode communities are required to develop effective biological management of these bioagressors as conventional control methods of PPN are inadequate and have persistent harmful effects. Fifty-nine organic vegetable soils in Souss-Massa were nematologically sampled, and assessment of taxonomic proliferation was made in relation to host species, geographical origin, and climatic and microclimatic factors. Twenty-four nematode genera were identified as obligate and facultative plant feeders. Taxonomic diversity increased from Chtouka to Taroudant and Tiznit provinces. Soil texture, organic matter, pH, nitrogen, zinc, magnesium, copper, altitude, and humidity and temperature were seen to effect driving roles in the abundance, distribution, and community structures of nematodes. The most prevalent taxa posing a high risk to organic agriculture of Souss Massa were needle nematodes (Longidorus spp.) and root-knot nematodes (Meloidogyne spp.). Edaphic and climatic variables effected nematode populations greatly. A combination of biological treatments and appropriate agroecological practices restricting important economic PPN growth and enhancing soil quality are required to achieve sustainable management in the area.

Plants are often subject to attack by fungi, nematodes and insects, which generate immense yield losses. Hence, the quest for crop protection solutions is ongoing, concurrent with greater awareness towards the use of synthetic chemicals in agricultural practice. Scientific research has shifted towards the use of natural products, which possess good efficacy and are environment friendly. This review details two classes of natural products. The first one is the plant essential oils with their volatile constituents, which have been proven to possess antifungal, nematicidal and insecticidal activities. The second class is the lipopeptides produced by antagonistic microorganisms. Their biological activities are discussed, as they have been shown effective against plant fungi and pests. Essential oils and lipopeptides have huge potential to be used as biopesticides. The combinatorial approach between essential oils, antagonistic microorganisms and lipopeptides for crop protection is discussed, potentially both can produce a synergistic effect, resulting from their combination against plant fungi, nematodes and pests.

Chemical profiles of essential oils hydrodistilled from whole plants of Senecio glaucus ssp. coronopifolius (Maire) Alexander and aerial parts of Ridolfia segetum (L.) Moris growing in Morocco were...

Essential oils are widely investigated as an alternative or complementary approach to broad-spectrum synthetic pesticides. In the present study, essential oil of Senecio glaucus subsp. coronopifolius was screened for its antifungal, nematicidal, acaricidal and repellent activities against the phytopathogens Botrytis cinerea, Meloidogyne javanica and Tetranychus urticae Koch under laboratory conditions. The volatile phase method (VF) and poisoned food method (PF) were adopted to test the antifungal activity of the essential oil. The oil gave 83% inhibition at 16 μL/ml using the PF method. VF method showed 86% inhibition of mycelial growth of B. cinerea at 0.8 μL/ml air. To check the nematicidal activity of the essential oil, two bioassays targeted the mortality of second stage juvenile (J2) and hatch inhibition of M. javanica eggs. 95% immobility of J2 and 92% inhibition of egg hatch were recorded at 16,000 ppm. The effect exerted by the oil was nematostatic. In the case of mites, a leaf dip bioassay revealed 100% mortality of T. urticae adults, and repellency of 24% after exposure to the oil at 80% concentration. Chemical profile of S. glaucus essential oil was obtained using GC–MS. Terpenic compounds, such as indicated α-pinene (26.2%), myrcene (11.4%), p-cymene (9.9%), β-pinene (7.7%), γ-muurolene (4%), deoxynivalenol (3.1%) and α-phellandrene (2.7%) were identified as the major components. The findings indicated that S. glaucus essential oil has the potential for management of these pathogens.

Meloidogyne javanica is considered as the most damaging nematode of vegetables in Morocco. Eco-friendly bionematicides are urgently required for its control. In vitro experiments were carried out to assess the direct effect of bioproducts of Peganum harmala against M. javanica. The bioassay showed extracts to be nematotoxic. Aqueous extracts of P. harmala exhibited reversible nematostatic activity. The estimated ID50 of the most active product in methanolic extracts was 368ppm. HPLC-MS of the methanolic extract revealed that total content of major alkaloids of P. harmala was approximately 12.162±0.637mg/g. Harmine (8.514±0.521mg/g) is the dominant alkaloid. In conclusion, Peganum harmala has a reversible nematostatic activity on second stage juveniles of M. javanica. The effect of P. harmala is due to its possession of a high content of β-carboline alkaloids, which warrant further experimentation. Bioproducts from P. harmala should be exploited through formulations for management of the root knot nematode.