The threat of cadmium (Cd) stress to agricultural soil environments, as well as their productivity attracting growing global interest. Tall fescue (Festuca arundinacea Schreb.) is a strong candidate for the remediation of heavy metals in soil. However, the joint analysis of Cd tolerance, physiological responses, and multifaceted plant microbiomes in tall fescue fields has not been extensively researched. Therefore, this study employed microbial sequencing (i.e., 16S and ITS sequencing) to investigate the differences in microbial community structure among various plant compartments of Cd-resistant tall fescue (cv. 'Arid3 ') and Cd-sensitive tall fescue (cv. 'Barrington'). Furthermore, we examined the mechanism of resistance to Cd by introducing three different bacteria and a fungus that were isolated from the 'Arid3 ' rhizosheath soil. It highlighted the potential application of enriched taxa such as Delftia, Novosphingobium, Cupriavidus and Torula in enhancing the activity of antioxidant defense systems, increasing the production of osmotic regulatory substances, and stimulating the expression of Cdresistance genes. This ultimately promoted plant growth and enhanced phytoremediation efficiency. This study shed light on the response mechanism of the tall fescue microbiome to Cd stress and underscored the potential of tall fescue-microbe co-culture in the remediation of heavy metal-contaminated areas.

Turf-type tall fescue [Schedonorus arundinaceus (Schreb.) Dumort., nom. cons.: TTTF] is a predominant turfgrass species for lawns throughout cool-humid regions, yet brown patch (caused by Rhizoctonia and Rhizoctonia-like species) can cause severe damage during the summer months. Hypothesized strategies to help minimize brown patch severity and decrease fungicide use includes establishing TTTFs with a high level of host resistance and minimizing summer nitrogen (N) applications. A two-year field study was conducted in West Lafayette, IN to determine the influence of late-spring and summer applied N at two application rates among five TTTF cultivars. Urea-N was applied monthly at two rates from April to July, totaling to 73.5 and 245.0 kg N ha-1. Turf performance was determined using visual ratings for turf quality, relative canopy greenness, disease severity (0-100%), and seasonal brown patch as calculated by area under the disease progress curve (AUDPC). Brown patch was generally not affected by N-rate for any cultivar in either study year. While none of the TTTF cultivars had complete brown patch resistance, cultivar differences were observed, with disease severity ranging from 9.8 to 39.0% and 20.0-51.9% in 2021 and 2022, respectively. Selecting a brown patch resistant cultivar reduced seasonal brown patch severity by 61% across study years compared to the most susceptible cultivars. This study demonstrates that summer N applications to TTTF lawns should not be completely avoided to reduce brown patch as previously suggested and emphasizes the importance of host resistance for disease management.