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Abstract Background Among the phytosanitary problems, affecting tomato crops in greenhouses heated by geothermal water in southern Tunisia, the tomato leaf miner, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is gaining prominence from year to year. Results This study determined the susceptibility of eggs, second-instar larvae of T. absoluta to commercial formulations of the entomopathogenic fungi (EPF) Beauveria bassiana and Lecanicillium muscarium at different doses (1010, 109, 108, 107 and 106 spores/ml). Pathogenicity tests were carried out under controlled laboratory conditions at 27 ± 1 °C, and RH of 75 ± 5%, showed that the three commercial formulations of B. bassiana R444 (Bb-Protec®), B. bassiana ATCC 74,040 (Naturalis®) and L. muscarium Ve6 (Mycotal®) were effective against eggs and second instar larvae of T. absoluta. Mortality rates of eggs and larvae were high with increasing the concentrations of the fungi. B. bassiana ATCC 74,040 was the most effective one, with an egg mortality rate of (71.42%) and larval mortality was greater than (80%), at the highest concentration of 1010 spores/ml. The lethal concentration required to kill 50% of eggs was 1.56 × 108, 1.73 × 109 and 1.09 × 1010 conidia/ml for B. bassiana ATCC, B. bassiana R444, and L. muscarium, respectively. After 7 days, the median lethal concentration (LC50) values against larvae were the lowest for B. bassiana ATCC with 2.63 × 107 and 4.76 × 106 conidia/ml by way 1 and way 2 treatments, respectively. Thus, these three formulations affected the emergence of pest’s adults. The fungi significantly reduced pupation and adult emergence. Only 50.25, 60.15 and 69.16% of T. absoluta adults emerged in the treatments with B. bassiana ATCC, B. bassiana R444, and L. muscarium, respectively. Conclusions Biological performances of the EPF showed the role of a biological control agent that can be played against T. absoluta within the framework of an Integrated Pest Management program.

River floods are listed among the natural disasters that can directly influence different aspects of life, ranging from human lives, to economy, infrastructure, agriculture, etc. Organizations are investing heavily in research to find more efficient approaches to prevent them. The Artificial Intelligence of Things (AIoT) is a recent concept that combines the best of both Artificial Intelligence and Internet of Things, and has already demonstrated its capabilities in different fields. In this paper, we introduce an AIoT architecture where river flood sensors, in each region, can transmit their data via the LoRaWAN to their closest local broadcast center. The latter will relay the collected data via 4G/5G to a centralized cloud server that will analyze the data, predict the status of the rivers countrywide using an efficient Artificial Intelligence approach, and thus, help prevent eventual floods. This approach has proven its efficiency at every level. On the one hand, the LoRaWAN-based communication between sensor nodes and broadcast centers has provided a lower energy consumption and a wider range. On the other hand, the Artificial Intelligence-based data analysis has provided better river flood predictions.

Land subsidence is an ongoing problem negatively affecting Victoria County along the Gulf Coast. Groundwater withdrawal and hydrocarbon extraction in the County are some of the known factors behind this geological hazard. In this study, we have used geospatial analysis and a conceptual model to evaluate land subsidence. A significant decline in the groundwater level in this area was noted from 2006 to 2016. The decline in the water level correlates with the major drought events along the Gulf Coast reported in earlier studies. These results are further corroborated by the emerging hotspot analysis performed on the groundwater data. This analysis divides the study area into intensifying, sporadic, and persistent hotspots in the northwest region and intensifying, persistent coldspots in the southeast region of Victoria County. Hydrocarbon production data show high oil and gas extraction from 2017 to 2021. There are a higher number of hydrocarbon production wells in the central and southern regions of the County than elsewhere. The conceptual models relate these events and suggest the existence of subsidence in the County, through which the water and hydrocarbon reservoirs in the study area may lose their reservoir characteristics due to sediment compaction.

International audience; To improve sustainable agriculture it becomes crucial to minimize the use of chemical inputs and involve new practices that are more productive and healthier for humans and environment. Biofertilization with arbuscular mycorrhizal fungi (AMF), known for increasing the productivity of many crops including potatoes, could be considered as one of these sustainable practices. The purpose of this study was to determine whether mycorrhizal inoculation can minimize chemical fertilization for potato (Solanum tuberosum L.), one of the most demanding species in mineral elements. Thus, by studying the effect of chemical fertilization and mycorrhizal inoculant on potato yield and soil quality. Two doses of chemical fertilizer (NP) corresponding to 50 % and 100 % of the recommended dose has been applied in the presence or not of the mycorrhizal inoculant. The results have shown that adding arbuscular mycorrhizal fungi in combination with 50 % of the chemical fertilizer dose gives the best effects. A significant increase in yield, root colonization, and P soil content has been observed (P < 0.001). Thus mycorrhizal inoculation could reduce the application of synthetic fertilizers and thus improve yield while preserving the environment.

The olive tree arranges no more water reserve that can be exploited during extremely dry periods. A failure of the olive yields observed during the last two decades. The annual production decreased from 150 000 tons to 50 000 tons of olives in the south of Tunisia. This degradation results, in fact from an obvious reduction in the biological activity of the ground. A new Strategy was employed to improve the organic status and restore the biological activity of the soil ground of the long-term. We have evaluated the effect of the of different plot treatment. A plot of olive tree speeded with 200 m3/ha dose of OMW during 10 years, P4; a plot of olive tree treated with tillage accompanied by 50 m3/ha dose OMW spreading lasting only a one year, P5 and a plot of olive tree cultivated with the introduction of the fig tree in parallel, P3. Untouched ground was used as control plot, P0. A comparison of these plots with a degraded ground of olive tree implanted since 1900, P2 and other ground degraded during 10 years, P1. The plot treated with OMW showed an OM value close to the value founded with P0 (Control Plot). The Phytotoxcity measured via germination index GI (percentage) was determined; an important increment ranged from 200% to 230% was obtained in the P3 and P5, respectively. Correlation analyses, among physiochemical parameters of soil and microbial biomass indicated several positive significant trends. The highest significant correlation was found between OM and TAMF (r=0.999, p<0.001). These results corroborate the notion that the microbial community structure is a good indicator of soil quality and the effects of different management practices, because the microorganisms respond against changes in soil management more rapidly than chemical or physical soil properties. However, in this work we found a negative correlation between respiration soil activity (Resp) and with OM (r=-0.533, p<0.05). In fact, CO2 sequestration took place. Indeed, increasing soil OM enhances the sequestering carbon dioxide (CO2) to mitigate anthropogenic greenhouse gas (GHG) emissions.

In Tunisia oases, the Mediterranean fruit fly (medfly) Ceratitis capitata affect heavily fruit production. The efficiency of the mass trapping technique based on the use of Cera Trap® was evaluated in two types of oases in the south of Tunisia against C.capitata. Our results showed that in the traditional oasis (mixed orchard), the medfly moves from one fruit specie to another according to their receptivity periods. The population density of medflies started low and peaked three times (16 Jun, 23 Jun, and 7 July) corresponding to the maturation period of apricot fig and peach fruits. The field study showed that medfly population density and rate of fruit damage were significantly lower in figs than in peaches and apricot. Modern oases have later apricot fruit maturity periods than traditional oases, and their medfly populations peaked at 19 Mai. Ceratrap® reduces 2, 2, and 6 times the population density of Mediterranean fruit fly and the rate of damaged fruits compared to untreated plots. These two parameters were twofold less in modern oases than in traditional oases. These results suggest that the use of traps at the density of 70 per ha is sufficient to protect crops under high population densities of C. capitata characterizing the traditional oases agricultural systems.

Ce travail s’inscrit dans le cadre d’un programme d’amélioration et de valorisation des ressources génétiques de la corète cultivée dans les régions arides tunisiennes. Les objectifs principaux de cette étude ont été : (i) la comparaison de la composition nutritionnelle (minéraux, composés phénoliques) et les activités antioxydantes de quinze populations de corète et (ii) l’identification des populations les plus performantes. Les résultats de l’analyse de variances (ANOVA) ont révélé des différences significatives entre les populations étudiées en termes de compositions minérales et phénoliques ainsi que de point de vue pouvoir antioxydant (DPPH). Les tests univariés de comparaison des moyennes et l’analyse de la classification hiérarchique globale ont permis d’identifier deux groupes intéressants de corètes ; Le premier groupe est présenté par les populations P11 et P15 ; qui se caractérisaient par la meilleure composition minérale ; et le second groupe a rassemblé les populations P4 et P12 ; qui se caractérisaient par la meilleure composition phénolique. Ces ressources génétiques doivent faire l’objet des études plus poussées pour achever le programme de sélection et le développement de nouvelles variétés plus performantes de corètes locales des régions arides tunisiennes.

Abstract Background The geothermal greenhouses in Southern Tunisia are an important axis of agricultural development. This sector faces many abiotic and biotic constraints that could threat its sustainability. Thus, the heated greenhouses encounter destructive pests such as the whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) and the two-spotted spider mite Tetranychus urticae (Koch) (Acari: Tetranychidae). Results This study aimed to assess the effect of the entomopathogenic fungi (EPF) Beauveria bassiana (strain ATCC and strain R444) and Lecanicillium muscarium strain Ve6 on simultaneous existence of T. urticae and B. tabaci in the host plants. The EPF had a significant effect on eggs and larvae of B. tabaci and on eggs and mobile forms of T. urticae in particular. The use of B. bassiana ATCC, B. bassiana R444 and L. muscarium strains Ve6 showed significant efficacies against B. tabaci larvae and eggs compared to untreated control. Indeed, the reduction percent of B. tabaci eggs varied between 42.65 and 58.52%. Thus, the efficacy against the number of B. tabaci larvae was in order to 65.04, 60.26 and 55.52% of B. bassiana strain ATCC, B. bassiana strain R444 and L. muscarium strain Ve6, respectively. In addition, these EPF were very effective on T. urticae eggs with a percentage reduction greater than 92.86%, whereas the percentage reduction in the T. urticae mobile forms varied between 95.11 and 98.52%. Conclusions Use of EPF will be an imperative to develop directed interventions at the integrated management of these two pests in protected and geothermal crops.