Description of the subject. The dependence of populations on natural formations affects the survival of plant species. Objectives. The objectives are to characterize the flora of plant formations with Erythrina senegalensis and Erythrina sigmoidea in the Guiriko region and to analyze the current state of their populations in order to guide their conservation. Method. Floristic and dendrometric data were collected following a targeted sampling after a survey of Erythrina plant formations. The plant formations selected for the study were the classified forests of Péni, Dindéresso, Kuinima, Kou, and the sacred woods of the sandstone hills of Kôrô. Results. A weakly similar floristic diversity (Cs = 0.45) with 213 and 165 species, respectively, in the E. senegalensis formation and the E. sigmoidea formation was observed with Rubiaceae, Combretaceae, Fabaceae-ceasalpinioideae, Anacardiaceae, Fabaceae-faboideae, and Fabaceae-mimosoideae as dominant families. The most dominant biological types are the Phanerophytes. A regressive population dynamic characterized by a near absence of large-diameter individuals and adult individual densities of 25.48 individuals·ha-1 for E. senegalensis and 13.15 individuals·ha-1 for E. sigmoidea was observed. The low densities of juveniles (< 50 individuals·ha-1) and the low renewal potentials (< 2 individuals·ha-1) observed constitute a major risk to the survival of Erythrina populations. The populations of E. senegalensis are more subject to debarking (13.30% of plants), while that of E. sigmoidea is more subject to bush fires (88% of plants). Conclusions. The renewal of these species is seriously compromised in the Guiriko region. Studies must be carried out on their regeneration modes, and special protection measures must be taken in conjunction with the populations to conserve and sustainably manage them.

Description of the subject. The rehabilitation of degraded lands is imperative, particularly in arid and semi-arid regions where environmental challenges such as salinity disturb ecosystem stability. Revegetation using medicinal and aromatic plants offers an economical and environmentally sustainable solution. Objectives. This study examines for the first time the germination and recovery potential of Pergularia tomentosa and Acokanthera oblongifolia (Apocynaceae) under varying saline conditions. Method. Seeds collected from the arid region of Algeria were exposed to eight salinity levels ranging from 0 to 800 mM NaCl for 20 days. Eleven essential germination traits associated with germination kinetics, speed, performance, seedling emergence and vigor, and germination recovery were evaluated. Results. The two-way ANOVA analysis revealed that salinity, species and their interaction had significant effects (p < 0.0001) on most germination traits. Salinity stress reduced germination, with P. tomentosa exhibiting greater tolerance compared to A. oblongifolia. No germination occurred under 300, 400 and 800 mM NaCl. Both species showed high significant recovery (80-90%), particularly at moderate salinity levels (300-400 mM NaCl), indicating adaptive mechanisms. Despite reduced recovery at 800 mM NaCl, P. tomentosa and A. oblongifolia maintained resilience, with recovery rates of 65.5% and 68.5%, respectively. Conclusions. These findings highlight the potential of these species for land restoration in saline-affected areas and for sustainable medicinal plant use. This research provides valuable insights into the germination performance of P. tomentosa and A. oblongifolia under salinity stress, offering promising applications in ecological restoration.

Description of the subject. Essential oils are volatile fractions produced through the special metabolism of plants. One significant biological application of essential oils in recent years has been their use as bioherbicides, due to their important biocide effect. Objectives. This study aims to identify the chemical constituents of Aloysia gratissima (Gillies & Hook.) Tronc. essential oil and assess its biocide potential. Method. This study describes, for the first time, the chemical constitution of the essential oils from seeds of A. gratissima. To verify possible biocide effect, lettuce seeds were submitted to different concentrations of essential oils from A. gratissima leaves (AG-LE-EO), flowers (AG-FL-EO), and seeds (AG-SE-EO) to evaluate germination percentage, mean germination time, synchrony of germination, and seedling length. Results. At concentrations of 800 μl·l-1, synchrony was positively influenced by (AG-LE-EO), increasing from 0.38 to 0.54. On the other hand, AG-SE-EO at concentrations of 800 μl·l-1 reduced lettuce germination from 90.8% to 64.4% and seedling length from 1.35 to 0.8 cm, besides increasing mean germination time, indicating biocide effects. Conclusions. These results are expected to lead to further trials to understand how the constituents of A. gratissima essential oils inhibit germination, making them a potential bioherbicide.

Description of the subject. In Algeria, agricultural advice tends to diversify and intensify as farmers’ needs become more specific. Objectives. The article aims to examine farmers' willingness to pay (WTP) for agricultural advisory services in a context of growing privatization. The goal is also to better understand the farmers’ advisory needs, their motivation and the socio-economic factors that influence the ability to afford privatized advice. Method. The study concerned citrus production and involved 362 farmers in the Mitidja plain (121 in the wilaya of Boumerdes, 241 in Blida). This study uses the contingent valuation method to estimate farmers' WTP for agricultural advice combined with an Ordinary Least Square model to analyze its determinants. Results. The results indicate that 90% of farmers are willing to pay for private advice, with an average estimated willingness to pay (WTP) of 1,269 DZD (9.42 $) per visit. The WTP is positively conditioned by the level of specialization in crop production, household size, the farmer’s level of education, the efficiency of the advisors and the satisfaction with the service. Additionally, it was found that farmers primarily seek advice on disease treatment and fertilizer use. Conclusions. This study demonstrates that the privatization of agricultural advisory services is possible in Algeria, provided that the advisory supply aligns farmers’ needs.

Description of the subject. The fall armyworm, Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae) is a major pest of staple cereal crops established in West Africa since 2016. Recently, earwigs have been observed consuming S. frugiperda immature stages in maize fields. Objectives. In this study, we evaluated the potential of earwigs, Diaperasticus erythrocephalus (Olivier) (Dermaptera: Forficulidae) to consume fall armyworm eggs and larvae in a laboratory setting. In addition, we compared the selectivity of the ten most used bio- and insecticides on this predatory species as well as on its prey for identifying products compatible with an integrated pest management strategy. Method. Predation was assessed by feeding earwigs ad libitum and susceptibility tests following the adapted IRAC 020 protocol. Results. Our results suggest that earwigs play an important role in the regulation of the fall armyworm: one individual consumes a mean of 90.3 ± 16.5 eggs or 36.4 ± 8.7 larvae per day. We found emamectin benzoate and spinetoram to be effective for controlling the fall armyworm, while not affecting the survival of this predator. On the other hand, chlorpyrifos-ethyl, methomyl and spinosad are not only effective against this pest but also highly toxic to the predator. Conclusions. We discuss the potential of these results in the development of an integrated pest management program against this invasive pest. In particular, we recommend training the farmers on natural enemy recognition and their conservation practices.

Description of the subject. The increasing occupation and exploitation of the Amazon has resulted in the increased conversion of forest areas into agricultural land or pasture. This often has negative impacts on soil and water dynamics. Therefore, there is a need for comparative studies between forest areas and those undergoing pasture conversion, in order to provide information to mitigate the impacts caused. Objectives. This study aimed to evaluate the physical and hydrological attributes of areas where forest has been replaced by pasture, located in the southern Amazon, Brazil. Method. The study areas are located in Humaitá, in the southern Amazon. For this study, five pasture areas, one natural pasture area, and one forest area were selected. A transect was established in each area containing fifteen sampling points. Mini trenches were opened at each point to collect soil samples (disturbed and undisturbed) in the 0.00-0.10 and 0.10-0.20 m depth. The samples collected in clods were dried in the shade and then crushed to obtain fine air dried soil. The volumetric rings (undisturbed samples) were saturated on the tension table and finally subjected to a penetrograph. Soil attributes such as sand, silt, clay, macroporosity, microporosity, total porosity, volumetric soil water content, and soil penetration resistance were also determined in the laboratory. The data obtained was tabulated and analyzed using descriptive statistics, a test of means to group the different environments, correlation analysis, and principal component analysis using multivariate analysis. Results. The results indicate that the conversion from forest to pasture harmed soil penetration resistance, volumetric soil water content, total porosity, and soil macroporosity. Pearson correlation in the first depth (0.00-0.10 m) revealed that sand content negatively correlated with microporosity, total porosity, and silt but no correlation with the other attributes. The soil penetration resistance showed a negative correlation with macroporosity, total porosity, and volumetric soil water content, suggesting a direct relationship where changes in the volumes of macroporosity, total porosity, and volumetric soil water content can significantly affect the soil penetration resistance. In the 0.10-0.20 m depth, the soil penetration resistance correlated negatively with macroporosity and positively with microporosity. The total porosity, correlated positively with microporosity and macroporosity and negatively with sand content. In this depth, macroporosity showed no correlation with microporosity. Conclusions. The forest and natural grassland areas stood out for having higher volumetric soil water content, microporosity, and total porosity, while the pasture areas were characterized by high penetration resistance. Amazonia, soil, environmental impact assessment, soil quality

The aim of the project Roles of agroforestry in the sustainable intensification of small farms and food security of societies in West Africa (RAMSES II, 2018 -2022) was to provide different ways of intensification of the four most represented cereal agroforestry parklands in West Africa: Faidherbia albida (tree), Guiera senegalensis (shrub), Vitellaria paradoxa (shea tree), and Piliostigma ssp. (shrub). Field works were conducted in Senegal and in Burkina Faso. The project's last meeting was held in Wageningen (The Netherlands) from 13 to 17 June 2022. The main results were shared. They were updated in 2023 and are available in the Deliverables, Publications, and Communications sections of the project website, https://www.ramsesiiagroforesterie.com

Description du sujet. Au Burkina Faso, le karité est une espèce hautement utilitaire conservée par les producteurs dans un système intégré d’utilisation des terres, dénommé parc agroforestier, dont la pérennité est menacée. Objectifs. Caractériser la structure des populations de karité afin de mettre en évidence les zones prioritaires pour la restauration. Méthode. Les sites d’étude, répartis selon un gradient climatique, sont au nombre de six. Des inventaires phytosociologiques ont été menés dans 10 parcelles permanentes de 2 500m² chacune par site, soit cinq parcelles dans des champs et cinq dans des jachères d’âges > 15 ans. Résultats. Il a été dénombré 41 espèces ligneuses réparties dans 30 genres et 16 familles. La structure des peuplements dans le secteur subsahélien est dégradée. Dans le secteur nord soudanien, la structure est caractérisée par une population de karité vieillissante dans les champs, alors que les jachères présentent un fort potentiel de régénération. Le sud soudanien est marqué par la prédominance des jeunes individus. Au premier stade, la régénération est importante mais elle disparait rapidement sous l’effet combiné de plusieurs facteurs mésologiques. Le secteur subsahélien et les champs dans le nord soudanien sont les sites prioritaires en termes de repeuplement des parcs à karité. Conclusions. Le karité doit faire l’objet de régénération assistée et de protection contre la coupe à l’échelle de son aire de distribution au Burkina Faso.

Description of the subject. Feed is the main variable cost in dairy farming. More efficient use of forage resources is one way to reduce production costs. Improving forage resource efficiency can start with a better assessment of the dry matter content and nutritional value of forages. Currently, analytical process time is often long and analyses are not repeatable while the quality of the fodder changes over time. Being able to analyze forages directly on-farm would make it possible to adapt the animal diet according to forage variability, in order to improve the profitability of the farm. Objectives. To propose in situ rapid analysis solutions to better characterize dry matter content and the chemical composition of fodder for assessing its feeding value. Method. The performance of three recently developed spectroscopic handheld devices, namely the Viavi’s MicroNIR 1700, the Ocean Insight’s FlameNIR and the Malvern Panalytical’s ASD FieldSpec 4, are evaluated to predict dry matter content and the chemical composition of fresh and unground grass silage in the framework of precision feeding and compared to the reference benchtop Foss’s XDS instrument. The conventional global PLS and local PLS are used as multivariate calibration methods. Results. The assessed handheld devices allow the dairy farmer to obtain a relatively precise quantitative prediction of the dry matter and crude fiber content (2.5% and 1.8% respectively on average, in terms of ratios between the local PLS error on fresh forage and the reference method error) in order to adapt the livestock diet. Crude protein, even if the prediction accuracy is lower (6.4%), is still well predicted. Higher errors are obtained for ash (9.2%), crude neutral (6.8%) and acid detergent fiber (6.9%). Conclusions. The studied devices should allow the dairy farmer to obtain a relatively precise quantitative prediction of those quality parameters in order to directly adapt the quantity of forage distributed to the animals. Performances could probably be improved by including more samples/spectra into the databases.

Introduction. Aquaponics is quickly expanding. Specific models and modeling tools have been developed within different studies. However, no study has yet attempted nor succeeded in bringing the aquaponic community around a common modeling project to centralize knowledge and develop an effective tool for users and professional growers. Literature. This paper reviews the relevant literature to provide an overview of the available simulation models and associated modeling tools. Furthermore, it identifies the current needs to lead further modeling developments. Conclusions. Several powerful models and modeling tools have been developed but are highly specific to their research scope and are often inaccessible. The modeling knowledge specific to aquaponics is at an advanced stage but is scattered among many different works. Therefore, it is evident that a shared and accessible modeling tool, which is currently missing, would greatly accelerate the development of aquaponics.