Plant growth-promoting rhizobia are known to improve crop performance by multiple mechanisms. However, the interaction between host plants and Rhizobium strains is highly influenced by growing conditions, e.g., heat, cold, drought, soil salinity, nutrient scarcity, etc. The present study was undertaken to assess the use of Rhizobium as plant growth promoters under abiotic stress conditions. Fifteen Rhizobium strains isolated from lentil root nodules were tested for phosphate solubilization activity (PSA) and phytohormones production under salt and drought conditions. The results showed that 15 Rhizobium strains were significant phosphate solubilizers, and indole acedic acid (IAA) and gibberellic acid (GA3) producers based on least significant difference (LSD) analysis (p ≤ 0.05). The highest rate of PSA was attributed to three strains namely, 1145N5, 1159N11, and 1159N32 with a range of 144.6 to 205.6 P2O5 (µg/mL). The highest IAA production was recorded in the strain 686N5 with 57.68 ± 4.25 µg/mL as compared to 50.8667 ± 1.41 µg/mL and 37.32 ± 12.59 µg/mL for Rhizobium tropici CIAT 899 and Azospirillum brasilense DSM-1690, respectively. Strain 318N2111 produced 329.24 ± 7.84 µg/mL of GA3 as against 259.84 ± 25.55 µg/mL for A. brasilense DSM-1690. R. tropici CIAT 899 showed tolerance to salt (5% NaCl) and drought (ψ = −2.6 MPa) stress, whereas strain 686N5 showed an extremely high level of salt-tolerance (5% NaCl) and moderate level of drought tolerance (ψ = −0.75 MPa). These results indicate different pathways for drought and salt tolerance mechanisms. The assessment of plant growth promoting (PGP) activities of Rhizobium showed differences between bacterial viability and bacterial PGP activity in terms of abiotic stress tolerance where bacterial PGP activity is interrupted before reaching the bacterial tolerance threshold. These results integrate a new concept of PGPR screening based on PGP activity under abiotic stress.

For over a century, the scientific community has had a comprehensive understanding of how rhizobia can promote the growth of legumes by forming nitrogen fixing nodules. Despite this knowledge, the interaction of rhizobia with non-legumes has remained largely ignored as a subject of study until more recent decades. In the last few years, research has shown that rhizobia can also associate with non-legume roots, which ultimately leads to the stimulation of growth through diverse direct and indirect mechanisms. For example, rhizobia can enhance growth through phytohormones production, the improvement of plant nutrient uptake, such as the solubilization of precipitated phosphorus, the production of siderophores to address iron needs, and also the reduction of ethylene levels through the ACC deaminase enzyme to cope with drought stress. Additionally, rhizobia can improve, indirectly, non-legume growth through biocontrol of pathogens and the induction of systemic resistance in the host plant. It can also increase root adherence to soil by releasing exopolysaccharides, which regulate water and soil nutrient movement. The objective of this review is to assess and analyze the existing knowledge and information regarding the mechanisms through which rhizobia promote the growth of non-legumes. By conducting a comprehensive analysis of these findings, we aim to gain new insights into the development of Rhizobium/non-legume interactions.

Enteric viruses are present in the environment as a result of the discharge of poorly or untreated wastewater. The spread of enteric viruses in the environment depend to human activities like stools of infected individuals ejected in the external environment can be transmitted by water sources and back to susceptible individuals for other cycles of illness. Among the enteric viruses Rotaviruses (RV) and Hepatitis A viruses (HAV) is the most detected in wastewater causing gastroenteritis and acute hepatitis. Therefore, it is of interest to climate change, mainly temperature and carbon Dioxide (CO2) variations, on Rotavirus and Hepatitis A as a model of enteric viruses present in the aquatic environment using computational modelling tools. The results of genetic ratio showed a negative correlation between the epidemiological data and the mutation rate. However, the correlation was positive between the temperature, CO2 increase, and the rate of mutation. The positive correlation is explained by the adaptation of the viruses to the climatic changes, the RNA polymerase of the RV induces errors to adapt to the environmental conditions. The simultaneous increase in number of infections and temperature in 2010 has been demonstrated in previous studies deducing that viral pathogenicity increase with temperature increase.

Ebola epidemic is a fatal disease due to Ebola virus belonging to Filoviridae; currently the viral evolution caused more than 50% of death worldwide. Among the eight proteins of ZEBOV, there are four structural proteins VP35, VP40, VP24, and NP, which have important functions in the intercellular pathogenic mechanisms. The multi-functionality of Ebola's viral proteins allows the virus to reduce its protein number to ensure its proper functioning and keeping the compact structure of the virus. Therefore, the aim of this chapter is to study the mechanism of replication and the roles of VP30, VP35, NP, and L in this process. We provide as well to highlight the influence of the virus on the immune system and on the VP24.

Chickpea is an important source of plant-based protein and mineral elements such as iron (Fe) and zinc (Zn). The development of superior high-yielding germplasm with high nutritional value becomes central for any breeding program. Chickpea biofortified and nutrient-dense seeds can contribute to mitigate many human health problems associated with protein and micronutrients deficiency. In this study, 282 advanced chickpea lines were grown under field conditions to evaluate their agronomic performances and nutritional quality value. The trial was conducted under winter planting conditions during the cropping season 2017/2018 at ICARDA-Marchouch research station, Morocco. Results revealed high genetic variation and significant differences between the tested genotypes for all studied parameters. Under field conditions, the grain yield (GY) varied from 0.57 to 1.81 (t.ha–1), and 100-seed weight (HSW) ranged from 23.1 to 50.9 g. Out of the 282 genotypes, only 4 genotypes (i.e., S130109, S130058, S130066, and S130157) combined both good agronomic performances (GY, HSW) and high nutritional quality (protein, macronutrients, and micronutrients). Protein content ranged from 18.9 to 32.4%. For the whole collection, Fe content varied from 31.2 to 81 ppm, while Zn content ranged from 32.1 to 86.1 ppm. Correlation analysis indicated that the studied traits were significantly intercorrelated, with negative correlation between protein content and Zn concentration. Positive correlations were observed between grain filling time (F2M) and the micronutrients Zn, Cu, and Mn and macroelements K and Mg. Low positive correlation was also recorded between Pr and Fe concentrations. No significant correlation was observed between Fe and Zn. Positive correlations observed between main agronomic and nutritional quality traits makes easy any simultaneous enhancement when combining these traits.

Fungal isolates of Fusarium were collected from symptomatic chickpea (Cicer arietinum L.)  plants growing in fields within Souk Tlat commune in the Gharb region. Morphological and molecular characterizations were performed of the fungal isolate N3 obtained from a chickpea plant. PCR amplification and sequencing of the internal transcribed spacer using the primers ITS1 and ITS4 was applied to identify the fungal isolate N3. The maximum similarity index of the fungus was found to be 99.33% with Fusarium equiseti (accession no. MT111122). In the pathogenicity test, both chickpea seed dip inoculation and soil infestation by the spore suspension of Fusarium isolate were adopted. Four weeks after chickpea seed inoculation, few plants emerged and those that emerged were stunted. A high percentage of inoculated seeds did not emerge and showed accentuated rot symptoms. Eight weeks after sowing seeds in infested soil, the obtained chickpea seedlings displayed root necrosis, browning at the crown, and wilting. In addition, these plants showed a foliar alteration index of 0.395. The re-isolation was positive for different parts of chickpea plants for both seed and soil inoculation. Fusarium equiseti isolate decreased the length of the root and aerial parts, and number of leaves and branches of the inoculated chickpea plants either by seed inoculation or soil infestation with values of 0.91 cm and 19.73 cm, 1.29 cm and 19.44 cm, 1.11 and 18.66, and 0.0 and 2.08 respectively, whereas the corresponding values for the control plants were 27.16 and 28.33 cm, 29.05 and 31.05 cm, 24.21 and 25.66, and 3.50 and 3.11, respectively. To the best of our knowledge, this is the first report of F. equiseti on chickpea (Cicer arietinum L.) in Morocco.

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