Ongoing impacts of climatic change especially moisture stress remain a global challenge to agricultural production and food security. Such abiotic effects directly influence soil microbial communities. Previously we demonstrated that polymeric hydrogels, able to provide specific interactions with soil microbial communities, enhance the dynamics and selectivity of ingress and colonisation of plant beneficial bacteria at soil microcosm scales. We now show that small quantities of osmotic hydrogels containing mannose nanofibrils specifically situated in close proximity to developing root zones provide enhanced microbial ingress, colonisation and continuous wetting pathways when contacting developing wheat root systems. These effectively create extensions to the natural rhizosphere sustaining significant beneficial rhizobacterial communities when under moisture stress. Sequencing studies, on wheat production soils undergoing a season of low average rainfall clearly showed microbial abundance increases and taxa selectivity in the rhizosphere-hydrogel regions compared to controls. Here wheat yields increased by about 20% with hydrogel addition compared to controls, which represented a 15% increase in the overall average yield in the region. This represents the first reported demonstration that developing rhizospheres may be readily engineered to consistently select their own distinct microbiome as nodes of functional microbial abundance significantly benefiting grain yield during abiotic stress. Thereby suggesting new opportunities to maintain grain yields during periods of drying climate via these fibrillar hydrogels.

气候变化的持续影响，尤其是水分胁迫仍然是对农业生产和粮食安全的全球挑战。这种非生物作用直接影响土壤微生物群落。先前，我们证明了能够与土壤微生物群落提供特定相互作用的聚合物水凝胶，可以在土壤微观尺度上增强植物有益细菌的入侵和定殖的动力学和选择性。我们现在显示，少量的含有甘露糖纳米纤丝的渗透水凝胶特别靠近发展中的根部区域，在接触发展中的小麦根部系统时可提供增强的微生物入侵，定植和连续的润湿途径。这些在水分胁迫下有效地形成了对天然根际的延伸，从而维持了重要的有益根际细菌群落。测序研究表明，与对照相比，在小麦平均降雨季节较低的生产土壤上，根际-水凝胶区域的微生物丰度增加，分类选择性更高。与对照相比，添加水凝胶的小麦单产增加了约20％，这表示该地区总体平均单产提高了15％。这代表了首次报道的论证，即发展中的根际可以很容易地工程化，以一致地选择其自身独特的微生物组作为功能性微生物丰度的节点，从而在非生物胁迫期间显着受益于谷物产量。