Agricultural yields are under constant jeopardy as climate change and abiotic pressures spread worldwide. Using rhizospheric microbes as biostimulants/biofertilizers is one of the best ways to improve agro-agriculture in the face of these things. The purpose of this experiment was to investigate whether a native arbuscular mycorrhizal fungi inoculum (AMF-complex) might improve caper (Capparis spinosa) seedlings’ nutritional status, their morphological/growth performance and photosynthetic efficiency under water-deficit stress (WDS). Thus, caper plantlets inoculated with or without an AMF complex (+AMF and −AMF, respectively) were grown under three gradually increasing WDS regimes, i.e., 75, 50 and 25% of field capacity (FC). Overall, measurements of morphological traits, biomass production and nutrient uptake (particularly P, K+, Mg2+, Fe2+ and Zn2+) showed that mycorrhizal fungi inoculation increased these variables significantly, notably in moderate and severe WDS conditions. The increased WDS levels reduced the photochemical efficiency indices (Fv/Fm and Fv/Fo) in −AMF plants, while AMF-complex application significantly augmented these parameters. Furthermore, the photosynthetic pigments content was substantially higher in +AMF seedlings than −AMF controls at all the WDS levels. Favorably, at 25% FC, AMF-colonized plants produce approximately twice as many carotenoids as non-colonized ones. In conclusion, AMF inoculation seems to be a powerful eco-engineering strategy for improving the caper seedling growth rate and drought tolerance in harsh environments.

The harm that invasive species cause to the environment has received a lot of attention. It is therefore appropriate that the current research was undertaken to evaluate the effects of invasion by Nicotiana glauca Graham on soil fertility by looking at (i) its contribution to the mycorrhizal potential of the soil, (ii) its impact on soil richness and diversity in terms of the arbuscular mycorrhizal fungi (AMF) community (iii), and its ability to modify the physicochemical characteristics in the invaded soil, specifically cleaning up heavy metal. The current study was conducted at Al Houz plain (Marrakesh region, Morocco), in heavily infested sites by N. glauca. The spores of AMF were isolated using the wet sieving process; the isolated spores were sorted for morphological features using a binocular microscope. The plant roots were thinned and colored before microscopic observation. The most probable number method was used to assess mycorrhizal soil infectivity. Heavy metal contamination in soils was characterized using an X-ray fluorescence spectrometer, and the pollution load index (PLI) was utilized to assess and compare the level of heavy metal contamination at each station. The ability of N. glauca to reproduce was evaluated in order to support one of its invasive characteristics. The estimate indicated that each plant might produce more than three million seeds. This significant number guarantees the plant a great capacity for reproduction and invasion. The extra-significant mycorrhizal potential, which can take the form of spores, mycelium, or vesicles that can regenerate mycorrhizae, was discovered by conducting soil analysis in the rhizospheric soils of N. glauca. This research demonstrated the strong mycotrophic capability of N. glauca and the large mycorrhizal potential of soils. Between 4.85 and 305.5 mycorrhizal propagules were considered to be the most probable number (MPN) per 100 g of dry soil. Based on color, shape and size, AMF were classified into five morphotypes corresponding to five genera. The isolated taxa of AMF with the most diverse spores were Glomus, Rhizophagus, Paraglomus, Scutellospora, and Sclerocystis. The Glomus genus was found to have spores in significant quantity. Furthermore, N. glauca demonstrated a potential involvement in the phytoremediation of damaged soils, with a high pollution load index demonstrating a particularly high accumulation of heavy metals. N. glauca is a highly mycotrophic plant that can boost soil mycorrhizal propagule stock. N. glauca has also been demonstrated to be a phytoremediation plant capable of cleansing contaminated soils. As a result, N. glauca could be considered as a prospective candidate for application in phytoremediation of polluted soils.

The present study aims to evaluate the effects of the exotic shrub Acacia cyanophylla Lindl. on soil fertility by studying 1) its ability to modify the soil physicochemical composition, 2) its contribution to the soil mycorrhizal potential and its impact on the richness and diversity of the arbuscular mycorrhizal fungi (AMF) community in the rhizospheric soil (RS), and finally 3) its atmospheric nitrogen fixation potential. The physicochemical analysis of the RS has shown that soil invasion by A. cyanophylla has a beneficial effect on its fertility; this advantage is demonstrated by the increase of the organic matter and the nutrient contents (N, P, K, Na, Ca) in the RS. Furthermore, the roots of this shrub exhibited broad AMF colonization, which confirms its high mycotrophic aspect. Four differentiated morphotypes of mycorrhizal spores were isolated from the RS of A. cyanophylla by use of the wet sieving method. In addition, the most probable number method showed that A. cyanophylla was capable of dramatically increasing the mycorrhizal potential of the soil. Indeed, more than 1,213 infectious propagules per one hundred grams of soil were detected in the RS of A. cyanophylla. Moreover, A. cyanophylla roots showed a significant presence of nodules indicating an active atmospheric nitrogen fixation. Counting revealed the presence of at least 130 nodules in the root fragments contained in 1 kg of soil. In conclusion, the biological invasion of sand dunes by the exotic shrub A. cyanophylla exhibited beneficial effects on the soil’s chemical composition and functioning, the activity of rhizobacteria in fixing atmospheric nitrogen, and phosphate bioavailability under the action of the native AMF community.