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The abundance of Panonychus citri McGregor 1916 (Acari: Tetranychidae) and its associated enemies (Euseius stipulatus Athias-Henriot, 1960; Typhlodromus sp.; Phytoseiulus persimilis Athias-Henriot, 1957) was studied on two 12-year-old citrus cultivars, specifically Clementine “Nules” (Citrus Clementina) and Valencia (Citrus sinensis), in the Gharb region of Morocco. Throughout the entire monitoring period in the Valencia late cultivar, the density of the spider mite P. citri on leaves was notably higher at 38.0% (n = 1,212 mobile forms). Predator P. persimilis exhibited a leaf occupancy of 25.0% (n = 812), followed by Typhlodromus sp. at 20.0% (n = 643). Conversely, the abundance of E. stipulatus was lower at 17.0% (n = 538). In the Nules variety, P. citri abundance recorded a higher percentage at 48.0% (n = 1,922). E. stipulatus emerged as the most abundant predator at 23.0% (n = 898), followed by P. persimilis with 16.0% (n = 639). Meanwhile, the population of Typlodromus sp. remained notably low at 13.0% (n = 498). Regarding the fluctuation of the different mites studied on the two cultivars across monitoring dates, the period from May 4 to June 1 was characterized by low temperatures and a diminished presence of mite populations (P. citri, E. stipulatus, Typhlodromus sp., and P. persimilis). However, from June 7 to June 19, characterized by high temperatures, a notable increase in the presence of mite populations was observed. As regards the effect of the variety on the different mites studied, the varietal impact was significant.

Orevactaene yellow pigment was produced by solid-state fermentation of broken rice using Epicoccum nigrum. The pigment was extracted using water as a solvent and subjected to stability studies at different temperatures (30, 40, 60, and 80°C), pH (4, 6, and 8), sterilization, and sunlight exposure treatment. The observed data were fitted in the first-order kinetic model. Yellow pigment stability was found to vary at different temperatures studied. At 30°C, only a 4% decrease in color intensity was observed after 2 h; at 40°C, an 8% decrease was observed, and at 80°C and pH 6.0, 17% of color intensity was lost. These results showed that the orevactaene pigment produced by E. nigrum is heat-sensitive and changes in color intensity should be expected in heat-processed products. After 180 min at 80°C, yellow pigments maintained 82 and 76% of the initial color at pH 6 and 8, while a 65% decrease in color intensity was observed at 80°C, pH 4. Autoclaving resulted in 69% decay and exposure of pigment to sunlight for 2 h showed 1% decay. The half-life period of the pigment at different temperatures varied from 82.5 to 5.25 h. The decimal reduction time decreased from 275 to 17.5 h with an increase in the temperature. Thermodynamic parameters for pigment decay at pH 6.0 were represented in terms of enthalpy ∆H, activation energy E a, free energy ∆G, and entropy ∆S. The values observed were 44.52–44.93, 48.48, 96.60–105.18 kJ/mol, and −170.50 to −171.85 J/mol/K, respectively. All these parameters help in predicting the quality changes in terms of appearance during thermal processing and optimizing the process.

Biotic stress caused by pests on citrus trees has become a major problem for ecologists around the world, hence the need to develop ecological approaches to surmount this stress. To evaluate the effectiveness of diverse control methods on the pest Panonychus citri and its predators, Euseius stipulatus, Phytoseiulus persimilis, and Typhlodromus sp. Different treatments were applied in orchards planted by Citrus clementina in the Gharb area of Morocco (T0 = treated by water only, T1 = spirodiclofen (the molecular formula is C21H24Cl2O4). 0.5 L/ha, T2 = 5% black soap 125 L/ha, Its ingredients are: argan oil, olive oil, black olive, salt, water, vegetable potash, without chemicals. T3 = mixture of two detergents; Oni product is composed of the following ingredients (sodium C12-13 parenth sulfate, and sodium C14-17 alkyl sec sulfonate) and Tide product with the following ingredients (sodium C10-16 alkylbenzene sulfonate, propylene glycol and sodium borate). Results obtained during the follow-up period showed that the black soap, spirodiclofen, and two detergent treatments provided a decrease in the P. citri population in comparison with plot treated by water during the whole monitoring period. We found 5,044 mobile forms of P. citri in the plot treated by water only, 1,544 forms in the plot treated with spirodiclofen, 3,002 forms in the plot treated with black soap, and 1,567 mobile forms in the plot treated with two detergents. This study demonstrated that all three treatments had a negative effect on the predators that survived in comparison to the control (T0), while the negative impact of spirodiclofen on beneficial phytoseiid mites was greater than that of black soap and detergents. However, the increase in temperature according to the follow-up weeks showed a significant effect on the evolution of the density of the studied mites. Unfortunately, the chemical products like spirodiclofen used against various citrus pests are considered toxic to phytoseiids and to the agro-ecosystem in general. This comparison aims to detect the effectiveness of black soap and mixtures of two detergents on P. citri and their impacts on its predators: E. stipulatus, P. persimilis, and Typhlodromus sp. to replace the use of pesticides by these alternative methods, which remain effective and environmentally friendly.

Apple scab, caused by the pathogenic fungus Venturia inaequalis, can result in significant economic losses. The frequent use of fungicidal products has led to the emergence of isolates resistant to commonly used active substances. Therefore, biological control offers a sustainable alternative for managing apple scab. In this study, eight Trichoderma isolates were evaluated against five different isolates of V. inaequalis isolated from the Fes-Meknes region. The biocontrol potential of these Trichoderma isolates had previously been demonstrated against other pathogens. The results indicated that the inhibition rate of mycelial growth of V. inaequalis obtained with Trichoderma spp. isolates ranged from 50% to 81%, with significant differences observed among the pathogenic isolates after 5 and 12 days of incubation. In addition, the in vitro tests with Trichoderma cell-free filtrates showed inhibition rates ranging from 2% to 79%, while inhibition rates ranged from 5% to 78% for volatile compound tests. Interestingly, the inhibition of spore germination and elongation was approximately 40–50%, suggesting the involvement of antifungal metabolites in their biocontrol activities. The in vivo bioassay on detached apple leaves confirmed the biocontrol potential of these Trichoderma isolates and demonstrated their ability to preventively control apple scab disease. However, their efficacies were still lower than those of the fungicidal product difenoconazole. These findings could contribute to the development of an effective biofungicide based on these Trichoderma isolates for reliable and efficient apple scab control. [ABSTRACT FROM AUTHOR]

This study investigates the infestation dynamics of Panonychus ulmi McGregor 1916 and its associated predators in Malus domestica borkh orchards across three towns in Morocco: Midelt, Ait Sebaa, and Imouzzer-Kender, situated in the Fez-Meknes and Draa-Tafilalt regions. Ait Sebaa (Fez-Meknes region), characterized by high temperatures and a lower altitude, exhibited a substantial increase in P. ulmi and its predators. In contrast, Midelt (Draa-Tafilalt region), with the highest altitude, demonstrated lower mite counts. Imouzzer-Kender (Fez-Meknes region), at an intermediate altitude, showed moderate mite levels. Detailed findings reveal a positive correlation between P. ulmi and temperature, as well as with phytoseiid mites. Conversely, a negative correlation exists between P. ulmi and altitude. Additionally, a positive correlation between phytoseiid mites and temperature is identified. Overall, this study provides valuable information on the ecological interactions between mites, temperature, altitude and humidity in distinct Moroccan regions, highlighting the need to take regional specificities into account in pest management strategies. [ABSTRACT FROM AUTHOR]

The present work aims to elaborate many juice formulas (F1 to F8) from two dried fruits (jujubes: Ziziphus lotus L. and dates: Phoenix dactylifera L.). Physicochemical and biochemical characterization of the formula juices shows that juices rich in dates fruits (F1, F3, F5, and F7) are loaded, on average, in total sugars (129.5 g/l), proteins (3.02 g/l), lipids (1.08 g/l), and carotenoid (0.02 mg/l), while juices rich in jujube fruits (F2, F4, F6, and F8) are overloaded, on average, in phenolic compounds (697 mg/l), flavonoids (6.32 mg/l), condensed tannins (2.1 mg/l), hydrolysable tannins (359.5 mg/l), and viscosity (1.062 mm 10-3 s). All formulations developed have a pH that rotates between 5.12 and 5.20. Total antioxidant capacity (CAT) reveals that formulations F1, F3, F5, and F7 show a strong activity compared to the other formulas. The DPPH test shows that all formulated juices have the same antioxidant profile with IC50 values lower than the template (BHT and Vit C). The FRAP test reveals that F2, F4, F6, and F8 formulas have a strong reducing power. Organoleptic evaluation by a jury shows that F4 formula is the best in terms of odor, aroma, and aftertaste agreeability. [ABSTRACT FROM AUTHOR]

Abstract: Oil bodies (OB) were extracted from argan kernels using an aqueous extraction method. The composition of OB revealed its lipid profile, which had a high content of stearic and palmitic acid. Besides, evidence suggested an association between OB and tocopherols. The physical properties of argan OB (AOB) showed that their size was around 1.9 μm and the ζ‐potential went from +17.7 mV at pH 2.0 to −32.25 mV at pH 8, with an isoelectric point around pH 5.1. OB were stable and small at pH 2.0, 7.0, and 8.0 but large near the pI. Additionally, AOB were stable against aggregation/coalescence even in high salt concentrations, and also against thermal processing (95 °C) with only a change in their interfacial properties. AOB emulsion showed interesting oxidative stability at different storage temperatures and heat treatment. Heat treatment and storage at low temperature preserved oleosins from degradation by the endogenous enzyme, and H‐oleosin 15 kDa resisted hydrolyzation even at a high storage temperature for 2 weeks. [ABSTRACT FROM AUTHOR]

The present work aims to elaborate many juice formulas (F1 to F8) from two dried fruits (jujubes: Ziziphus lotus L. and dates: Phoenix dactylifera L.). Physicochemical and biochemical characterization of the formula juices shows that juices rich in dates fruits (F1, F3, F5, and F7) are loaded, on average, in total sugars (129.5 g/l), proteins (3.02 g/l), lipids (1.08 g/l), and carotenoid (0.02 mg/l), while juices rich in jujube fruits (F2, F4, F6, and F8) are overloaded, on average, in phenolic compounds (697 mg/l), flavonoids (6.32 mg/l), condensed tannins (2.1 mg/l), hydrolysable tannins (359.5 mg/l), and viscosity (1.062 mm 10-3 s). All formulations developed have a pH that rotates between 5.12 and 5.20. Total antioxidant capacity (CAT) reveals that formulations F1, F3, F5, and F7 show a strong activity compared to the other formulas. The DPPH test shows that all formulated juices have the same antioxidant profile with IC 50 values lower than the template (BHT and Vit C). The FRAP test reveals that F2, F4, F6, and F8 formulas have a strong reducing power. Organoleptic evaluation by a jury shows that F4 formula is the best in terms of odor, aroma, and aftertaste agreeability., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2020 Meryem Benidir et al.)