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Drought stress (DS) is one of the severe abiotic stresses that cause reductions in agricultural production. This study was conducted to examine the efficiency of arbuscular mycorrhizal fungi (M: consortium) and plant growth-promoting rhizobacteria (R: Z2 and Z4 strains, B: CHIN14, AAP22, AAP2, and CHIN15 strains), individually or in combination, as an appropriate strategy to improve durum wheat productivity under two water regimes: well-watered (75% FC) and DS (25% FC). DS exhibition reduced biomass, stomatal conductance, stem water potential, and increased malondialdehyde and hydrogen peroxide content. Under DS, AMF or B promoted plant growth, such as shoot height by 49 and 17%, respectively; by activating the photosynthetic mechanism and increasing the synthesis of proline content by 369% in plants treated with AMF, and antioxidant enzyme activities, such as polyphenoloxydase (PPO), in leaves by 36% in plant inoculated with B. After the experiment, total organic matter and carbon of the soil were improved by single application of B by 99 and 317%, respectively. This finding implies that the combination of mycorrhiza and PGPR regulates the physiological and biochemical processes utilized by wheat to cope with drought and improves the comprehension of the soil-plant relationship. [ABSTRACT FROM AUTHOR]

• Physiological and biochemical processes in durum wheat were affected by salt stress. • Inoculation with AMF and supplementation of compost mitigated salinity damaging effects, by enhancing plant photosynthesis ability and up regulating the antioxidant metabolism and osmolytes accumulation. • The enhanced tolerance to salinity was specifically related to elevated activities of peroxidase, and polyphenol oxidase under salt stress. Salinity is one of the most harmful abiotic stresses that affect wheat development and metabolism. The main objective of this study was to evaluate the potential effects of biostimulants/biofertilizers as an environment-friendly practice for improving wheat tolerance to salinity. A greenhouse experiment was conducted on a durum wheat variety: Carioca. The wheat seedlings were treated with a pure strain of arbuscular mycorrhizal fungus (M; Rhizoglomus irregulare) and /or compost (C; made from olive pomace with olive mill wastewater under non-saline, medium and high saline (100 and 200 mM NaCl) conditions. The results showed that C application significantly decreased mycorrhizal infection. Salinity reduced growth, physiological functioning, and biochemical processes. However, selected biostimulants/biofertilizers application, especially C alone, mitigated the negative effects of salinity by improving wheat shoot dry weight (65%), root dry weight (22%), phosphorus uptake (544%), and stomatal conductance (180%) than control under 200 mM NaCl. In addition, C application alone and/or M treatments improved osmotic adjustment and antioxidant system, maintained a higher stem water potential, reduced malondialdehyde and hydrogen peroxide content and increased glomalin secretion in soil. These results showed that compost and/ or Rhizoglomus irregulare could mediate salt tolerance and enhance wheat production in degraded areas. [ABSTRACT FROM AUTHOR]

Drought is one of the major threats to food security in arid and semi-arid regions. Therefore, significant changes in agricultural production systems will be required to meet the challenges of food security while addressing water scarcity. Prickly pear is a drought tolerant plant, as well as a source of sustainable food and feed. Nonetheless, in dry conditions, its growth and performance are restricted. The aim of this study was to evaluate the effect of arbuscular mycorrhizal fungi (AMF), vermicompost (Vc) or the combination of AMF + Vc on yield, growth and physio-chemical parameters of cactus grown under field drought conditions. Two irrigation regimes were applied, non-irrigated (grown under rainfed conditions) and irrigated plants (8 mm of water per week). After eight months of cultivation, the finding demonstrated that drought reduced growth, physiological and biochemical parameters of cactus. However, the application of biostimulants, especially Vc and AMF + Vc, can mitigate the negative effect of drought by increasing cladode dry weight (93% and 109%), total chlorophyll (78% and 75%), total phenolic content (83% and 81%). Those treatments are also efficient in enhancing activities of enzymatic and non enzymatic antioxidants in cactus cladodes and fruits. These results suggest that the use of these biostimulants can mitigate the challenges associated with drought, by improving the physiological and biochemical responses of cactus. [ABSTRACT FROM AUTHOR]

Mycorrhizal symbiosis, the mutually beneficial association between plants and fungi, has gained significant attention in recent years due to its widespread significance in agricultural productivity. Specifically, arbuscular mycorrhizal fungi (AMF) provide a range of benefits to grain and oil crops, including improved nutrient uptake, growth, and resistance to (a)biotic stressors. Harnessing this symbiotic interaction using molecular and systems biology approaches presents promising opportunities for sustainable and economically-viable agricultural practices. Research in this area aims to identify and manipulate specific genes and pathways involved in the symbiotic interaction, leading to improved cereal and oilseed crop yields and nutrient acquisition. This review provides an overview of the research frontier on utilizing molecular and systems biology approaches for harnessing the symbiotic interaction in mycorrhizal symbiosis for grain and oil crop cultivation. Moreover, we address the mechanistic insights and molecular determinants underpinning this exchange. We conclude with an overview of current efforts to harness mycorrhizal diversity to improve cereal and oilseed health through systems biology. [ABSTRACT FROM AUTHOR]

Drought stress is one of the most serious constraints that prevents plants from attaining their full potential, particularly in arid and semi-arid regions. Among notable drought-tolerant plants, prickly pear stands as a plant capable of tolerating daring water stress conditions, thanks to its water storage and CO 2 uptake capabilities. However, its full potential remains constrained under drought stress. The use of biostimulants such as arbuscular mycorrhizal fungi (AMF) and vermicompost (Vc) can help the plant to mitigate drought. The present study provides insights into the effects of an AMF, a vermicompost at a dose of 5%, and their combination on growth, and biochemical responses of prickly pear cladodes under severe water stress (SWD), moderately watered (MD), and well-watered (WW) treatments (15, 30 and 50% of field capacity (FC), respectively). AMF + Vc treatment showed the highest values of AMF colonization and growth parameters under drought stress. The application of these biostimulants increased physiological and biochemical parameters, under water deficit, and led to a decline in malondialdehyde (MDA) and hydrogen peroxide (H 2 O 2), notably on plants treated with AMF + Vc. Overall, the results pointed out the role of AMF and vermicompost as strategic applicable tools in better mitigation of drought stress in the prickly pear. • Growth performance of prickly pear cactus was significantly affected by drought. • A dual application of AMF and/or vermicompost improved water uptake in cactus. • AMF and/or vermicompost application can reduce drought damage in cactus. • Biostimulants application reduced oxidative marquers in cactus plant under drought. • AMF and/or vermicompost application can assist in drought tolerance in cactus. [ABSTRACT FROM AUTHOR]

Agricultural activities depend heavily on irrigation in arid and semi-arid climates, which are one of the most water-limited areas, reducing agricultural productivity. As the climate changes, the lack of precipitation is expected to aggravate in these areas, requiring careful management of water use. Subsurface water retention technology (SWRT) may hold promise as a management tool to save water use and improve crop drought resistance. In this context, the effect of SWRT on tomato yield, growth, physiology, and biochemical characteristics, as well as soil characteristics under two regimes of water (100% field capacity (FC) and 50% FC) in open field conditions, was investigated. The results here suggest that drought affected tomato performance. Nevertheless, SWRT application significantly increased tomato yield (38%), chlorophyll fluorescence (3%), gas exchange (39%), and chlorophyll total content (49%), as well as soil fertility characteristics, with significant increases in organic matter (23%) and assimilable phosphorus contents (25%) compared with the control. Furthermore, it resulted in a significant reduction in enzymatic antioxidant activities and polyphenol and significant improvement in fruit quality by increasing protein content. This technique should be used as a valuable strategy to save irrigation water and mitigate the negative effects of water deficiency on tomato plants in arid and semi-arid regions. [ABSTRACT FROM AUTHOR]

Biofertilizers have been reported to increase resistance of plants to drought. However, the effects of combination of arbuscular mycorrhizal fungi (AMF) with compost (C + AMF) on carob under drought and recovery have not been studied and remain poorly understood. The effects of C + AMF on the growth performance, physiological and biochemical traits of carob under drought and recovery was evaluated. The experiment was divided into two phases: (i) phase 1: half of the plants were well-watered (WW) and other half were subjected to drought stress (DS), and (ii) phase 2: rewatering the plants under DS (REC). Our findings showed that C + AMF promoted growth, nutrient content, and modified physiological and biochemical parameters in carob during the two phases. After recovery, water content, stomatal conductance, the maximum photochemical efficiency of PSII, photosynthetic pigments and plant uptake of mineral nutrients were significantly higher in shoots of C + AMF than in controls. Moreover, C + AMF reduced to a greater degree the accumulation of hydrogen peroxide and malondialdehyde content in C + AMF than in controls. It can be concluded that AMF combined with compost can successfully be applied as biofertilizers for improving the growth, physiological and biochemical parameters in carob during both DS and after REC. [ABSTRACT FROM AUTHOR]

Prickly pear cactus (Opuntia ficus‐indica) is a medicinal plant that plays important economic and ecological roles in arid and semi-arid regions. This study aims to assess the effectiveness of arbuscular mycorrhizal fungi (AMF) inoculation isolated from O. ficus-indica rhizosphere and/or vermicompost supplementation on growth and biochemical properties of newly developed O. ficus-indica cladodes. The experiment was conducted in a greenhouse with four treatments: control, AMF inoculation and vermicompost application individually or in combination with AMF. After eight months of cultivation, the results showed that the application of AMF and/or vermicompost improved growth and stimulated mycorrhizal colonization. Treatments with AMF, vermicompost, and AMF + vermicompost treatments increased sugar and protein contents by 30, 55 and 67% and 21, 60 and 84%, respectively. In addition, these treatments improved the superoxide dismutase, catalase and polyphenol oxidase activities and total phenolics and flavonoids content. Consequently, the same treatments enhanced the inhibition of the free radical 2, 2-diphenyl-1- picrylhydrazyl (DPPH) activity by 58, 52 and 33%, respectively compared to control plants, which reflects the highest antioxidant activity. In conclusion, our findings suggest that AMF combined with vermicompost induced the greatest effect on the different parameters tested and could improve the growth and development of cactus plants. [ABSTRACT FROM AUTHOR]

The present study aims to elucidate the impact of arbuscular mycorrhizal fungi (AMF) inoculation and partial root drying (PRD), or regulated deficit irrigation (RDI) techniques on the growth, physiology and biochemistry of melon plants under three water regimes: control (100% of field capacity (FC) (C100%)), 75% of FC (PRD75%) and 50% of FC (PRD50% and RDI50%). The experiment was carried out under semi-controlled greenhouse conditions and the AMF inoculum used was a field-sourced native Aoufous consortium. Obtained results show an increase in shoot dry weight in inoculated plantss under PRD75% and PRD50% by 12 and 9% respectively, compared to C100%. Mycorrhizal plants under PRD75%, PRD50% and RDI50% maintained the highest relative water content, leaf water potential (Ψleaf) and stomatal conductance, as well as photosynthetic pigments, compared to their respective control plants. In addition, PRD75%+AMF and RDI50%+AMF recorded the highest values of evapotranspiration. AMF increased total soluble sugars, proteins, and proline contents in response to PRD and RDI. Our results demonstrate that PRD75%, PRD50% and RDI50% in combination with AMF were the most effective treatments for improving growth, physiological and biochemical traits of melon under water stress. [ABSTRACT FROM AUTHOR]

In the current study, an eco-friendly management technology to improve young carob (Ceratonia siliqua L.) tree tolerance to water deficit was set up by using single or combined treatments of arbuscular mycorrhizal fungi (AMF) and/or compost (C). Two groups of young carob have been installed: (i) carob cultivated under well-watered conditions (WW; 70% field capacity (FC)) and (ii) where the plants were drought-stressed (DS; 35% FC) during 2, 4, 6, and 8 months. The effect of used biofertilizers on the course of growth, physiological (photosynthetic traits, water status, osmolytes, and mineral content), and biochemical (hydrogen peroxide (H2O2), oxidative damage to lipids (malondialdehyde (MDA), and membrane stability (MS)) traits in response to short- and long-term droughts were assessed. The dual application of AMF and C (C + AMF) boosted growth, physiological and biochemical parameters, and nutrient uptake in carob under WW and DS. After eight months, C + AMF significantly enhanced stomatal conductance by 20%, maximum photochemical efficiency of PSII by 7%, leaf water potential by 23%, chlorophyll and carotenoid by 40%, plant uptake of mineral nutrients (P by 75%, N by 46%, K+ by 35%, and Ca2+ by 40%), concentrations of soluble sugar by 40%, and protein content by 44% than controls under DS conditions. Notably, C + AMF reduced the accumulation of H2O2 and MDA content to a greater degree and increased MS. In contrast, enzyme activities (superoxide dismutase, catalase, peroxidase, and polyphenoloxidase) significantly increased in C + AMF plants under DS. Overall, our findings suggest that the pairing of C + AMF can mediate superior drought tolerance in young carob trees by increasing leaf stomatal conductance, cellular water content, higher solute concentration, and defense response against oxidative damage during the prolonged period of DS. [ABSTRACT FROM AUTHOR]

Date palm (Phoenix dactylifera L.) is an important crop in arid zones and plays significant ecological and socio-economic roles. During the last decades, date palm groves were subjected to degradation due to extensive soil exploitation and low soil fertility. The use of biological techniques is essential to improve date palm development. The present work aims at assessing the effect of two different doses of compost (5% and 20%) and inoculation with the arbuscular mycorrhizal fungus (AMF) Rhizoglomus irregulare on growth and development of date palm seedlings. The treatments comprised control and application of 5 and 20% of compost with R. irregulare individually or in combination. Growth, physiological, histological, and mycorrhization traits were assessed. Obtained results showed that compost applied at a low dose (5%) alone or in combination with the AMF stimulated root length, leaf area, root dry weight, nitrogen, phosphorus and potassium contents, stomatal conductance and chlorophyll fluorescence and increased the number of sclerenchyma fibers, the number of vascular bundles, root diameter, and lignification of the endodermis of date palm seedlings compared to control. Compost at low doses combined or not with AMF can successfully be applied as biofertilizers for improving the growth and development of date palm. [ABSTRACT FROM AUTHOR]

The impact of soil amendment with compost and/or application of arbuscular mycorrhizal fungi (AMF) on the resistance of tomato to Verticillium dahliae was evaluated. The frequency and intensity of mycorrhization decreased in V. dahliae inoculated plants. Application of compost and AMF significantly improved plant growth, stomatal conductance and chlorophyll fluorescence compared to infected and non infected controls. The combination of these biostimulants reduced the disease severity and incidence and the leaf alteration index compared to pathogen-infected control plants. Mycorrhized and compost amended soil recorded a maximum decrease in plants malonyldialdehyde accumulation in the presence of V. dahliae. The combination of compost and AMF resulted in a significant improvement of superoxide dismutase, catalase, peroxidase and polyphenoloxidase activities in tomato leaves and roots compared to the control treatment in the presence of the pathogen. Similarly, yield and quality of tomato fruits were significantly improved by the dual application of compost and AMF. [ABSTRACT FROM AUTHOR]

• Growth and histological parameters as well as nutrient uptake of date palm were improved by arbuscular mycorrhizal fungus (AMF) combined with seaweed extract (SWE). • The physiological parameters of date palm under nutrient deficient system were enhanced by AMF+SWE treatment. In oases ecosystems, date palm (Phoenix dactylifera L.) is a plant that has several socio-economic and environmental roles. During the last decades, the cultivation of date palm and its development are threatened by several constraints, in particular, organic and mineral matter depletion. The main objective of this study was to evaluate the effects of a seaweed extract (SWE) derived from the brown algae Fucus spiralis and an arbuscular mycorrhizal fungus (AMF) strain (Rhizophagus irregularis DAOM 197198) as well as their combination on the growth and development of the date palm (P. dactylifera L.). Growth, physiological, and histological parameters were evaluated. The results show that AMF combined with SWE induced the greatest effect. Indeed this treatment significantly increased the total dry weight, leaf area, stomatal conductance, and nitrogen (N) and phosphorus (P) levels by 27, 36, 48, 377, and 94%, respectively, compared to the control. Potassium (K) and calcium (Ca) contents were highly increased by AMF compared to other treatments. The results also show an enhancement in quantum yield of the photochemistry of PSII (Fv/Fm) by the AMF, SWE, and AMF+SWE treatments. The number of sclerenchyma fibers in AMF+SWE, SWE, and AMF treatments was increased by 681, 164 and 154% respectively, while, the number of vascular bundles was improved by 24% in the SWE treatment compared to the control. Lastly, the results indicated the positive effect of SWE or AMF and, especially, their combination as an efficient practice to improve growth and development of date palm. [ABSTRACT FROM AUTHOR]