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La moisissure grise causée par Botrytis cinerea provoque des dégâts sur plus de 200 espèces de cultures dans le monde. B. cinerea sporule pour former une pourriture grise sur les feuilles, les tiges et les fruits. Pour lutter contre B. cinerea, des fongicides synthétiques sont utilisés. Ces derniers mettent en danger la santé humaine et environnementale en plus de la résistance qu'ils peuvent occasionner chez les souches de B. cinerea. Les alternatives écologiques sont des solutions appropriées pour contrôler la moisissure grise tout en maintenant l’équilibre environnemental. L’objectif de cette étude est d'évaluer l’effet des isolats de Pseudomonas issus de la rhizosphère de la tomate sur B. cinerea. Les résultats ont montré que les 76 isolats testés inhibent le développement de B. cinerea in vitro. Cinq isolats de Pseudomonas (Q6B, Q13B, Q7B, Q14B et Q1B) ont provoqué des niveaux d'inhibition significatifs allant de 65 à 73%. Par ailleurs, ces isolats ont également inhibé B. cinerea sur les feuilles et le fruit de la tomate. Pour tenter d'élucider les mécanismes d'action, les cinq isolats ont montré une production des métabolites antifongiques tels que les sidérophores, le cyanure d'hydrogène et d’autres enzymes. Les résultats de cette étude ont montré que les isolats de Pseudomonas Q6B, Q13B, Q7B, Q14B et Q1B ont une forte efficacité dans la lutte biologique contre B. cinerea et peuvent être utilisés pour une lutte écologique durable.

Argania spinosa (L.) Skeels is a unique endemic species in Morocco, renowned for its ecological characteristics and socio-economic importance. In Morocco, recent years have seen an exacerbation of the harmful effects of climate change, leading to an alarming decline in the natural regeneration of this species in its original habitats. It seems that the only viable solution lies in the domestication of this genetic heritage. This study marks the first in-depth investigation of the impact of various climatic and edaphic factors on the morphological and physiological traits of Argania spinosa young plants, assessed in six separate orchards and observed over four seasons (March 2022 (Winter), June 2022 (Summer), November 2022 (Autumn), and March 2023 (Winter)). A climatic assessment was carried out at each site, including measurements of rainfall, maximum and minimum temperatures, mean temperature, air temperature, and wind speed. The soil was analyzed for the pH, electrical conductivity (EC), water content, limestone (CaCO 3 ), Kjeldahl nitrogen (N), available phosphorus (P 2 O 5 ), organic matter (OM), and carbon/nitrogen ratio (C/N). To gain a better understanding of the morphophysiological characteristics of young argan seedlings, we carried out various observations, such as measuring the height and diameter of aerial parts, and the water content of leaves (WCL) and branches (WCB), quantifying chlorophyll (mg/m 2 ) and leaf area. The results revealed a significant impact of edaphic and climatic factors on the morphophysiological parameters of young argan trees. Results revealed significant correlations of young argan plants between edaphic and climatic factors and morphophysiological parameters. The Tamjloujt site, characterized by protective vegetation cover, showed optimal growth conditions with the highest leaf and branch water content (46.89 ± 4.06% and 37.76 ± 3.51%, respectively), maximum height growth (91.33 ± 28.68 mm), trunk diameter (24.85 ± 3.78 mm), and leaf surface area (69.33 ± 19.28 mm 2 ) during Summer 2022. The Saharan zone of Laqsabi exhibited peak chlorophyll concentrations (506.9 ± 92.25 mg/m 2 ) during Autumn 2022, due to high temperatures. The mountainous environment of Imoulass negatively impacted plant growth (mean height: 52.61 ± 12.37 mm; diameter: 6.46 ± 1.57 mm) due to harsh climatic and edaphic conditions. This research provides vital knowledge regarding the environmental factors influencing the establishment of young argan plants within the Argan Biosphere Reserve. This contributes to the development of more effective domestication strategies and the restoration of agroecosystems. The aim is to use this knowledge to promote the rehabilitation and sustainability of argan agroecosystems.

Anaerobic digestion (AD) of lignocellulosic wastes (LW) has garnered substantial interest because of its notable energy and nutrient recovery, along with its potential for reducing greenhouse gas emissions. However, the LW is resistant to degradation, and its hydrolysis typically requires harsh conditions, hence the need for a pretreatment. Conducting a life cycle assessment (LCA) to evaluate the pretreatment of LW is an effective way to assess the environmental impacts associated with various pretreatment methods. This work evaluates and compares three scenarios for handling lignified tomato green waste (TGW), generated in the Greater of Agadir in Morocco, in terms of their environmental impacts and energy demand, using the LCA approach, performed with OpenLCA software. To achieve this aim, the impact of these scenarios on 11 indicators is studied. The analyzed management options include a base case scenario S0 where TGW undergoes a direct anaerobic digestion (AD), organosolv pretreatment of TGW followed by AD of the free-lignin fraction (S1), and choline chloride-based deep eutectic solvent (DES) delignification followed by AD of the free-lignin fraction (S2). The data used for the analysis comes from the Tamelast landfill, laboratory tests, literature, CML-IA baseline and Monte Carlo simulation calculations. The results obtained showed that the introduction of pretreatments in S1 and S2 mitigates significantly the environmental impact in different categories compared to S0. Scenario S2, with its enhanced recovery processes, shows the highest positive environmental contributions, despite its reliance on additional external electricity. S1 and S0 both respect energy circularity. Through this study, it has been demonstrated that chemical pretreatment of LW is energy, water and solvent-intensive and requires a large investment. It opens up perspectives for further works on pretreatment using natural DES technology, its development and its applications in the delignification of ligneous biomass on an industrial scale., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Argania spinosa is among the most important species of the Moroccan forest in terms of ecological, environmental, and socio-economic aspects. However, it faces a delicate balance between regeneration and degradation in its natural habitat. Hence, the efforts to preserve and regenerate argan forests are crucial for biodiversity, soil quality, and local livelihoods, yet they face challenges like overgrazing and climate change. Sustainable management practices, including reforestation and community engagement, are vital for mitigating degradation. Similarly, exploiting the argan tree's rhizosphere can enhance soil quality by leveraging its rich microbial diversity. This approach not only improves crop growth but also maintains ecosystem balance, ultimately benefiting both agriculture and the environment. This enrichment can be achieved by different factors: mycorrhizae, plant extracts, algae extracts, and plant growth-promoting rhizobacteria (PGPR). The benefits provided by PGPR may include increased nutrient availability, phytohormone production, shoot, root development, protection against several plant pathogens, and disease reduction. In this study, the effect of rhizobacteria isolated from the Agran rhizosphere was evaluated on germination percentage and radicle length for Argania spinosa in vitro tests, growth, collar diameter, and branching number under greenhouse conditions. One hundred and twenty (120) bacteria were isolated from the argan rhizosphere and evaluated for their capacity for phosphate solubilization and indole acetic acid production. The results showed that 52 isolates could solubilize phosphorus, with the diameters of the solubilization halos varying from 0.56 ± 0.14 to 2.9 ± 0.08 cm. Among 52 isolates, 25 were found to be positive for indole acetic acid production. These 25 isolates were first tested on maize growth to select the most performant ones. The results showed that 14 isolates from 25 tested stimulated maize growth significantly, and 3 of them by 28% (CN005, CN006, and CN009) compared to the control. Eight isolates (CN005, CN006, CN004, CN007, CN008, CN009, CN010, and CN011) that showed plant growth of more than 19% were selected to evaluate their effect on argan germination rate and radicle length and were subjected to DNA extraction and conventional Sanger sequencing. The 8 selected isolates were identified as: Brevundimonas naejangsanensis sp2, Alcaligenes faecalis , Brevundimonas naejangsanensis sp3, Brevundimonas naejangsanensis sp4, Leucobacter aridicollis sp1, Leucobacter aridicollis sp2, Brevundimonas naejangsanensis sp1, and Staphylococcus saprophyticus . The results showed that Leucobacter aridicollis sp2 significantly increased the germination rate by 95.83%, and the radicle length with a value of 2.71 cm compared to the control (1.60 cm), followed by Brevundimonas naejangsanensis sp3 and Leucobacter aridicollis sp1 (2.42 cm and 2.11 cm, respectively). Under greenhouse conditions, the results showed that the height growth increased significantly for Leucobacter aridicollis sp1 (42.07%) and Leucobacter aridicollis sp2 (39.99%). The isolates Brevundimonas naejangsanensis sp3 and Leucobacter aridicollis sp1 increased the gain of collar diameter by 41.56 and 41.21%, respectively, followed by Leucobacter aridicollis sp2 and Staphyloccocus saprophyticus (38.68 and 22.79%). Leucobacter aridicollis sp1 increased the ramification number per plant to 12 compared to the control, which had 6 ramifications per plant. The use of these isolates represents a viable alternative in sustainable agriculture by improving the germination rate and root development of the argan tree, as well as its development, while increasing the availability of nutrients in the soil and consequently improving fertilization.

Argania spinosa (L.) Skeels is an endemic species to Morocco that has multiple uses. It plays multiple important roles in terms of its botanical, ecological, and economic properties. However, the domestication of this species will open up considerable economic opportunities for Morocco. Here, for the first time, we assessed the effect of different doses of compost and NPK fertilizers on the vegetative growth parameters, biochemical and antioxidant potential of the Argania spinosa plant, and soil properties. Over a two-year period (2022-2023), eight different treatments were applied across two experimental sites. These treatments included the following: T0 (Control), T1 (F1-80.50.70 g NPK/plant), T2 (F1-125.75.100 g NPK/plant), T3 (F2-160.100.140 g NPK/plant), T4 (F2-250.150.200 g NPK/plant), T5 (F1-2.5 kg/plant compost), T6 (F1-5 kg/plant compost), T7 (F2-5 kg/plant compost), and T8 (F2-10 kg/plant compost), with F1 and F2 being the frequencies of application. We compared several doses of fertilizers with no fertilization as a control. The results showed a significant influence of the compost and NPK fertilizer on the vegetative growth parameters. For the Tamjlojt site, the first year is important because treatments T3 and T4 significantly increased height by 71.94 ± 21.15% and 74.31 ± 12.31%, respectively. For the circumference, the results showed a significant improvement by the treatments T4 and T3, and T1 demonstrated the highest gain. For the collar diameter, all treatments showed a significant difference. The most notable difference was observed with treatments T3 and T7 with 115.63 ± 33.88% and 101.09 ± 20.84%, respectively. For the Rasmouka site, the second year was the most important. The treatments with the most important height increase were T7 and T8, with a value of 43.14 ± 10.06% and 36.44 ± 9.95%; the same was observed for collar diameter as a significant increase was found in T8 and T7 with a value of 55.05 ± 15.7% and 54.08 ± 9.64%. For the circumference parameter, the treatments that increased significantly this parameter were T8 and T7 with a value of 53.36 ± 15.11% and 50.34 ± 11.29% in 2023. In addition, the highest content of carbohydrates was recorded for the treatment T3 with a value of 148.89 ± 8.11 (mg EG/g). For phenolic determination, the highest value was 2532 ± 457.13 (µg GAE/mL), shown for treatment T1. For flavonoids, the treatments that showed a significant effect were T1 and T6 with a value of 2261.98 ± 184.61 and 1237.70 ± 95.65 (µg QE/mL), respectively. For the impact on soil properties, the electrical conductivity, at the Tamjlojt site, treatment T1 showed a significant increase to 1139.00 ± 241.30 (ms/cm), while at the Rasmouka site, treatment T8 showed a significant increase to 303.33 ± 9.33 (ms/cm). Concerning organic carbon, all treatments resulted in increased percentages of this parameter in the soil. For the Tamjlojt site, the T7 treatment had a significant positive effect on this parameter with a value of 0.87 ± 0.12%. For the Rasmouka site, the T3 treatment increased the percentage of organic carbon with a value of 1.17 ± 0.07%. In addition, the organic matter content showed an improvement with a value of 2.02 ± 0.12%. As there are no previous studies in Argania spinosa fertilization, this study greatly contributes to our understanding of the benefits of using different fertilizers at different doses, in particular T8 and T7 as organic fertilizers and T3, T4 as chemical ones, on argan growth, the biochemical and antioxidant properties of leaves, and its soil properties.

The argane tree ( Argania spinosa L.) is a mostly self-incompatible species that must be cross-pollination. However, the cross-pollination is often insufficient to obtain a desirable fruit yield in the absence of compatibility between the orchard's argane trees. Proper pollination design is therefore essential to ensure a supply of compatible pollen. In this study, pollen germination and pollen development following cross- and self-pollination were investigated in A. spinosa . The choice of compatible parents or a pollinizer is currently a new research topic for the production of argane fruits in the framework of argane farming programs. Different pollination experiments were designed with two main objectives: (i) to study cross/self-(in)compatibility in the argane tree, and (ii) to determine the degree of compatibility between selected superior genotypes for pollination strategies to improve fruit set in argane orchards. Thus, to determine if a pollination deficit exists, experiments were carried out on 14 genotypes, and 5421 flowers served as sampling. The germination rate of pollen was lower than 50% for three genotypes, and only four genotypes bloom twice a year. From cross-pollination trials, traits related to the mother trees, such as the shape of the fruit and fruit ripening duration, are not influenced by the gene flow transmitted by pollens. Self-pollination was very low (0.2%) for both hand- and free self-pollination but the highest fruit set rate observed was 5.3%. Based on the pollen effect study results, it can be concluded that different pollen sources affected the fruit set. Thus, the choice of an efficient pollinizer genotype must be inter-compatible with the main variety, bloom at the same time, and be regular (no alternation). This is the first time that a pollinizer tree was reported and studied for argane. To meet future argane farming requirements, the number and location of compatible pollinizers is very important in the argane orchard design. This design of pollination remains to be checked by alternately planting a row of pollinizer trees or inter-rows with main varieties.

In agroecosystems, soil biodiversity is increasingly becoming more recognized as providing benefits to both plants and human health. It performs a wide variety of ecological services beyond the recycling of nutrients to plant growth and manage pests and diseases below the economic injury level. This study investigated the effects of three Pseudomonas isolates (Q172B, Q110B and Q036B), isolated from untreated tomato rhizospheric soil, as a biological control agent of Bemisia tabaci which is a key pest of tomato crops. The study was conducted under laboratory and glasshouse conditions and the water treatment was used as a control. Adult mortality rates were assessed during three days at 24h interval and larva mortality rates were evaluated during six days after treatment at 48h interval. Results indicate that Q036B isolate has a faster effect on B. tabaci adult and larvae. Under laboratory conditions, all three Pseudomonas isolates (Q110B, Q036B and Q172B) have a significant effect on B. tabaci adult mortality compared to control. The earliest and the most important mortality rate of 76% was recorded by Q036B. Two isolates Q036B and Q110B caused a significant mortality on B. tabaci larvae; with highest mortality effect (79%) was observed for Q036B compared to control. However, Q172B has no mortality effects on B. tabaci larvae under laboratory conditions. In glasshouse conditions, only Q036B provided high mortality rates of 91% at 168h after treatment. The results of this study indicate that the Pseudomonas isolate Q036B significantly suppresses B. tabaci in tomato plant and could substitute the excessive use of chemicals. Current research indicates that soil biodiversity could be promising to preserve agro-ecological sustainability., Competing Interests: The authors have declared that no competing interests exist.

Pseudomonas isolates have frequently been isolated from the rhizosphere of plants, and several of them have been reported as plant growth-promoting rhizobacteria. In the present work, tomato (Solanum lycopersicum) seeds were germinated in greenhouse conditions, and the seedling height, length of plants, collar diameter and number of leaves were measured from plants grown in soil inoculated by bacterial isolates. Pseudomonas isolates were isolated from the rhizosphere. We used the Newman-Keuls test to ascertain pairwise differences. Isolates were identified as a new Pseudomonas species by rpoD gene sequencing. The results showed that isolates of Pseudomonas sp. (Q6B) increased seed germination (P = 0.01); Pseudomonas sp. (Q6B, Q14B, Q7B, Q1B and Q13B) also promoted seedling height (P = 0.01). All five isolates promoted plant length and enlarged the collar diameter (P = 0.01). Pseudomonas sp. (Q1B) also increased leaf number (P = 0.01). The investigation found that Pseudomonas isolates were able to solubilize phosphate, produce siderophores, ammonia, and indole-3-acetic acid and colonize the roots of tomato plants. This study shows that these five novel Pseudomonas sp. isolates can be effective new plant growth-promoting rhizobacteria.