{
  "id": 2256152,
  "title": "Phyllosphere microbes decouple nutrient enrichment from plant productivity",
  "url": "https://urgent.news/2026/08/20/phyllosphere-microbes-decouple-nutrient-enrichment-from-plant",
  "topic": "science",
  "section": "Science",
  "published": "2026-08-20T00:00:00.000Z",
  "source": {
    "name": "bioRxiv",
    "slug": "biorxiv",
    "url": "https://www.biorxiv.org/content/10.64898/2026.08.16.745140v1?rss=1"
  },
  "original_language": "en",
  "account": "Recent research challenges the long-standing theory that nutrient enrichment should always boost plant productivity. While resource limitation theory suggests that adding nutrients will enhance plant growth, the presence of phyllosphere microbes can change this dynamic. These microbes can either help plants acquire nutrients, compete for them, or alter the plant-environment interface. However, it remains uncertain whether phyllosphere microbiomes actually mediate the relationship between nutrient enrichment and ecosystem productivity.\n\nTo investigate this, researchers conducted experiments with a duckweed polyploid complex, a group of closely related species. In controlled microcosm ecosystems, the team observed that when microbes were absent, added nutrients did indeed increase plant productivity. But when microbes were present, the same nutrient enrichment failed to boost productivity, despite the abundance of residual nutrients in the system. This decoupling of nutrient enrichment from productivity was not due to direct competition among microbes for nutrients or the microbes' known functions related to pathogenicity, oxygen depletion, or acidification.\n\nInstead, the researchers found that nutrient enrichment triggered the formation of biofilms, which are sticky layers of microbes that can cling to surfaces. These biofilms may physically restrict plants' access to the available nutrients, thereby decreasing productivity. Additionally, the microbes' actions led to increased phosphorus immobilization and transformation. Yet, these microbial activities did not explain a decline in the ecosystem's phosphorus removal capacity. Instead, the observed decline was primarily driven by reduced plant productivity resulting from the biofilm formation. Consequently, a significant amount of phosphorus remained unused in the system.\n\nInterestingly, the research also found that the polyploid ducksweed species with greater ploidy levels (i.e., more complete sets of chromosomes) exhibited a stronger advantage in nutrient-use efficiency. This benefit was not linked to their ability to tolerate the microbes' effects. In summary, the findings indicate that phyllosphere microbiomes play a crucial role in mediating how nutrient enrichment translates into ecosystem functioning.",
  "summary": "Resource limitation theory predicts that nutrient enrichment enhances plant productivity. Yet plant-associated microbes can modify this relationship by facilitating nutrient acquisition, competing for resources, or restructuring the plant-environment interface. These processes generate contrasting predictions for whether added nutrients are converted into plant population growth. Whether…",
  "key_points": [],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}