Root Knot Nematode (RKN, Meloidogyne incognita) is one of the greatest damaging soil pathogens causes severe yield losses in cucumber and many other economic crops. Here, we evaluated the potential antagonistic effect of the root mutualistic fungus Piriformospora indica against RKN and their impact on vegetative growth, yield, photosynthesis, endogenous salicylic acid (SA) and its responsive genes. Our results showed that P. indica dramatically decreased the damage on shoot and root architecture of cucumber plants, which consequently enhanced yield of infested plants. Likewise, P. indica colonization clearly improved the chlorophyll content and delimited the negative impact of RNK on photosynthesis. Moreover, P. indica colonization exhibited a significant reduction of different vital nematological parameters such as soil larva density, amount of eggs/eggmass, eggmasses, females and amount of galls at cucumber roots. Additionally, the results showed that SA level was significantly increased generally in the roots of all treatments especially in plants infested with RKN alone as compared to control. This suggests that P. indica promoting SA levels in host cucumber plant roots to antagonize the RKN and alleviate severity damages occurred in its roots. This higher levels of SA in cucumber roots was consistent with the higher expressional levels of SA pathway genes PR1 and PR3. Furthermore, P. indica colonization reduces PR1, PR3 and increased NPR1 in roots of RKN infested cucumber plants when compared to non-colonized plants. Interestingly, our in vitro results showed that direct application of P. indica suspension against the J2s exhibited a significant increase in mortality ratio. Our results collectively suggest that P. indica promoting morphological, physiological and SA levels that might together play a major important role to alleviate the adverse impact of RKN in cucumber.

Water stress is the most critical aspect restricting the development of agriculture in regions with scarce water resources, which requires enhancing irrigation water-saving strategies. The current work discusses the potential application of the plant-strengthening root endophyte Piriformospora indica against moderate (25% less irrigation water) and severe (50% less irrigation water) water stress in comparison to the optimum irrigation conditions of greenhouse cucumbers. P. indica improved growth, nutrient content, and photosynthesis apparatus under normal or water-stress conditions. On the other hand, moderate and severe water stress reduced yield up to 47% and 83%, respectively, in non-colonized cucumber plants, while up to 28 and 78%, respectively, in P. indica-colonized plants. In terms of water-use efficiency (WUE), P. indica improved the WUE of colonized cucumber plants grown under moderate (26 L/kg) or severe stress (73 L/kg) by supporting colonized plants in producing higher yield per unit volume of water consumed by the crop in comparison to non-colonized plants under the same level of moderate (43 L/kg) or severe (81 L/kg) water stress. Furthermore, P. indica increased the indole-3-acetic acid (IAA) content, activity levels of catalase (CAT) and peroxidase (POD) with an apparent clear reduction in the abscisic acid (ABA), ethylene, malondialdehyde (MDA), proline contents and stomatal closure compared to non-stressed plants under both water-stress levels. In addition, chlorophyll a, b, a + b contents were increased in the leaves of the colonized plants under water-stress conditions. This improvement in chlorophyll content could be correlated with a significant increment in the transcripts of chlorophyll biosynthesis genes (protochlorophyllide oxidoreductase [POR], chlorophyll a oxygenase [CAO]) and a reduction in the chlorophyll degradation genes (PPH, pheophorbide a oxygenase [PAO], and red chlorophyll catabolite reductase [RCCR]). In conclusion, P. indica has the potential to enhance the cucumber yield grown under moderate water stress rather than severe water stress by improving WUE and altering the activity levels of antioxidant enzymes and chlorophyll metabolism-related genes.

Salinity is a widespread abiotic stress that devastatingly impacts wheat growth and restricts its productivity worldwide. The present study is aimed at elucidating biochemical, physiological, anatomical, gene expression analysis, and agronomic responses of three diverse wheat genotypes to different salinity levels. A salinity treatment of 5000 and 7000 ppm gradually reduced photosynthetic pigments, anatomical root and leaf measurements and agronomic traits of all evaluated wheat genotypes (Ismailia line, Misr 1, and Misr 3). In addition, increasing salinity levels substantially decreased all anatomical root and leaf measurements except sclerenchyma tissue upper and lower vascular bundle thickness compared with unstressed plants. However, proline content in stressed plants was stimulated by increasing salinity levels in all evaluated wheat genotypes. Moreover, Na+ ions content and antioxidant enzyme activities in stressed leaves increased the high level of salinity in all genotypes. The evaluated wheat genotypes demonstrated substantial variations in all studied characters. The Ismailia line exhibited the uppermost performance in photosynthetic pigments under both salinity levels. Additionally, the Ismailia line was superior in the activity of superoxide dismutase (SOD), catalase activity (CAT), peroxidase (POX), and polyphenol oxidase (PPO) enzymes followed by Misr 1. Moreover, the Ismailia line recorded the maximum anatomical root and leaf measurements under salinity stress, which enhanced its tolerance to salinity stress. The Ismailia line and Misr 3 presented high up-regulation of H+ATPase, NHX2 HAK, and HKT genes in the root and leaf under both salinity levels. The positive physiological, anatomical, and molecular responses of the Ismailia line under salinity stress were reflected on agronomic performance and exhibited superior values of all evaluated agronomic traits.

Background: Arbuscular mycorrhiza (AM) refers to a symbiotic association between plant roots and fungi that enhances the uptake of mineral nutrients from the soil and enables the plant to tolerate abiotic and biotic stresses. Although previously reported RNA-seq analyses have identified large numbers of AM-responsive genes in model plants, such as Solanum lycopersicum L., further studies are underway to comprehensively understand the complex interactions between plant roots and AM, especially in terms of the short- and long-term responses after inoculation.Results: Herein, we used RNA-seq technology to obtain the transcriptomes of tomato roots inoculated with the fungus Rhizophagus irregularis at 7 and 30 days post inoculation (dpi). Of the 1,019 differentially expressed genes (DEGs) in tomato roots, 635 genes showed differential expressions between mycorrhizal and non-mycorrhizal associations at the two time points. The number of upregulated DEGs far exceeded the number of downregulated ones at 7 dpi, and this difference decreased at 30 dpi. Several notable genes were particularly involved in the plant defense, plant growth and development, ion transport, and biological processes, namely, GABAT, AGP, POD, NQO1, MT4, MTA, and AROGP3. In addition, the Kyoto encyclopedia of genes and genomes pathway enrichment analysis revealed that some of the genes were involved in different pathways, including those of ascorbic acid (AFRR, GME1, and APX), metabolism (CYP, GAPC2, and CAM2), and sterols (CYC1 and HMGR), as well as genes related to cell division and cell cycle (CDKB2 and PCNA).Conclusion: These findings provide valuable new data on AM-responsive genes in tomato roots at both short- and long-term postinoculation stages, enabling the deciphering of biological interactions between tomato roots and symbiotic fungi.

In light of the fact that climate change has emerged as one of the difficulties confronting the global food system, researchers are obligated to work toward developing fundamental crops, particularly wheat, to combat environmental stress, including drought and salt. In the present study, genetic engineering was used to transfer the Arabidopsis MDAR1 gene, which controls the buildup of ascorbic acid (AsA) to make bread wheat less likely to be sensitive to salt stress. The biolistic bombardment was used to transfer cDNA from the Arabidopsis thaliana plant that encodes MDAR1 into Bobwhite 56 cultivar wheat plants. A molecular investigation was performed on six different transgenic lines to confirm the integration of the transgene, the copy number, and the expression of the transgene. There were one to three copies of the transgene, and there was no association found between the number of copies of the transgene and All the data generated or analyzed during this study are included in this published article [and its supplementary information files].the presence of its expression. Compared to plants that were not transgenic, the amount of ascorbic acid (AsA) that accumulated in the transgenic plants was twice as high. ROS concentrations are significantly lower in transgenic plants compared to non-transgenic plants under both control and salt stress conditions, effectively reducing oxidative stress. By cultivating transgenic T2 plants in a greenhouse, we were able to determine whether they were able to tolerate the potentially damaging effects of salt stress (200 mm). The study concluded that transgenic wheat plants that consistently expressed the MDAR1 gene become tolerant to salt stress with improvement in growth characteristics.