Drought stress profoundly affects native desert plants’ survival and performance. Among all the abiotic stresses, drought is considered a major constraint that influences the structure and functions of desert ecosystems. Arid desert ecosystems are characterized by prolonged drought, extreme temperatures, high solar radiation, water scarcity, high salinity, scarcity of soil nutrients, and poor soil structure. Such extreme desert environments are the toughest regions on earth, which present enormous challenges in conserving plant survival, growth and reproduction. Despite the predominance of these environmental conditions, native desert plant species that grow in desert environments develop complex adaptation strategies and resistance mechanisms to ameliorate the abiotic and biotic stresses in the extreme environments including changes in biochemical, physiological, and morphological levels. Arbuscular mycorrhizal fungi (AMF) form positive symbiotic associations with a considerable percentage of terrestrial plants as their host, induce distinct impacts on plant growth and protect plants from abiotic stresses. However, it is necessary to advance our understanding of the complex mechanisms associated with AMF-mediated and other dark septate endophytes (DSE)-mediated amelioration of native desert plants’ drought stress resistance and associated biological adjustments such as changes in hormone balance, water and nutrient status, stomatal conductance and osmotic adjustment, antioxidant activity, and photosynthetic activity. This review provides an overview of the relationships of mycorrhiza and fungal endophytes involved in drought stress tolerance, summarizing the current knowledge and presenting possible mechanisms mediated by AMF to stimulate drought tolerance associated with native desert plants. We discuss the research required to fill the gaps and provide suggestions for future research.

Drought is the most critical limiting factor affecting plant survival, development, and adaptation in the desert ecosystem. Native desert plant species are adaptable natural biomass crops of the desert’s ecosystem. These native species use water efficiently and tolerate drought and other environmental constraints. In addition, they sustain moderate nutritional values that are essential in terms of maintaining optimum vegetation, development and productivity, and tolerating natural grazing. The objective of this study was to quantify the biomass production and nutritive values of three native desert grass species as influenced by drought stress, that is, 100, 75, 50, and 25% potential evapotranspiration (ETp). Three native desert grasses, viz., Cenchrus ciliaris, Lasiurus scindicus, and Pennisetum divisum were grown in pots, irrigated with fresh water in a greenhouse, and investigated for their drought tolerance and nutritive values. The results showed that the grasses differ in their responses to drought stress by controlling stomata conductance (gs). The gs increased significantly (p < 0.001) with adequate irrigation (100 and 75% ETp) and decreased with 50 and 25% ETp in all species. Under moderate drought stress (75 and 50% ETp), all desert grasses used the water efficiently and produced a considerable dry matter yield and stable amounts of nutritive value. At 50% ETp, all desert species showed significant increase (p < 0.001) in root biomass than shoots that increased water absorption to survive a drought environment. L. scindicus exhibited a significantly higher increase (p < 0.001) in root formation at 25% ETp than the 100% ETp treatment. In all the grass species, the protein contents increased as drought stress increased. No significant differences in fat content were detected under all irrigation conditions, while the ash content was significantly (p < 0.001) influenced by severe drought stress. Under natural desert conditions, these adjustments may reduce transpiration demand relative to water deprivation, leading to improved species establishment and supported adaptation to severe desert environments. Understanding the physiological responses and the requirements of desert plant species can be an excellent way to restore ecological functions and biodiversity conservation in a desert environment.

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Implementing large-scale restoration programs requires in-depth understanding about the salinity tolerance of native species, especially in the Arabian Peninsula where salinity is one of the most serious problems. Seedlings of four native species, namely Vachillea pachyceras, Haloxylon salicornicum, Rhanterium epapposum, and Farsetia aegyptia, were subjected to different salinity treatments (1.6 (control), 3, 5, 7, and 10 dS/m). Survival, growth performance, biomass and proline accumulation were assessed after six months of salinity exposure. Different mineral concentrations in the shoot and root tissues were assessed before and after the salinity exposure. Our results showed that salinity influenced the growth parameters, enhanced proline accumulation and changed the contents of essential elements. However, the effects of salinity stress on the growth and other parameters were largely species-specific. Proline accumulation increased with an increase in the salinity level in all the species. However, the mineral content in the root and shoot tissues showed variation, depending on the species and the level of salinity stress. Overall. H. salicornicum appeared to be the most tolerant species, as its seedling survival (100% at EC 10), and root and shoot biomass were impacted minimally; meanwhile, F. aegyptia (16.7% seedling survival at EC 10) appeared to be highly sensitive to the salinity. Data generated from this study will be helpful in screening the suitable species according to their salinity tolerance in salt-affected areas.

In this study, a coastal research site north of Kuwait Bay faces sand encroachment, floods, and wave erosion. The plantation project’s infrastructure was improved by fencing 1.2 km2 with barbed wire. The heavily deteriorated environment has coppice dunes of Nitraria retusa and Lycium shawii around single, double, or triple plants. To manage mobile sand and dust and protect the research centre, 21,500 Nitraria and Lycium were planted and irrigated with brackish water (around 7000 TDS). In order to aerodynamically shift and/or trap mobile aeolian sediments, the vegetation was planted in a V-shape facing the north-westerly wind. A closer gap (about 1m between plants) on the side facing the primary wind and widened toward the inner edges of the gated area controls mobile sand and dust. This projected design stabilizes the soil, protects against floods and wave erosion, enhances flora and animals, and controls aeolian activity. Mobile sand and dust yearly rates in the downwind traps were reduced by 94% and 64.5%, respectively. Native vegetation can control mobile sand and dust, according to this. Such systems can be more efficient with proper design and plant spacing.