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SUMMARY Global warming, climate change, and industrial pollution are altering our environment subjecting plants, microbiomes, and ecosystems to an increasing number and complexity of abiotic stress conditions, concurrently or sequentially. These conditions, termed, “multifactorial stress combination” (MFSC), can cause a significant decline in plant growth and survival. However, the impacts of MFSC on reproductive tissues and yield of major crop plants are largely unknown. We subjected soybean (Glycine max) plants to a MFSC of up to five different stresses (water deficit, salinity, low phosphate, acidity, and cadmium), in an increasing level of complexity, and conducted integrative transcriptomic‐phenotypic analysis of their reproductive and vegetative tissues. We reveal that MFSC has a negative cumulative effect on soybean yield, that each set of MFSC condition elicits a unique transcriptomic response (that is different between flowers and leaves), and that selected genes expressed in leaves or flowers of soybean are linked to the effects of MFSC on different vegetative, physiological, and/or reproductive parameters. Our study identified networks and pathways associated with reactive oxygen species, ascorbic acid and aldarate, and iron/copper signaling/metabolism as promising targets for future biotechnological efforts to augment the resilience of reproductive tissues of major crop plants to MFSC. In addition, we provide unique phenotypic and transcriptomic datasets for dissecting the mechanistic effects of MFSC on the vegetative, physiological, and reproductive processes of a crop plant.
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Dominant foliar endophytes influence soybean yield and transcriptome
Abstract Microorganisms associated with plants can affect nutrient and water acquisition, plant defenses, and ecological interactions, with effects on plant growth that range from beneficial to antagonistic. In Glycine max (soybean), many studies have examined the soil microbiome and the legume–rhizobium relationship, but little is known about foliar endophytes, their effects on plant biomass and fitness, and how plants respond to their presence. To address these questions, we inoculated Glycine max with field-collected isolates of previously isolated, dominant strains of Methylobacterium and Colletotrichum in either sterile or non-sterile soil. We then used RNAseq to compare the transcriptomic responses of plants to single- and co-inoculation of endophytes. We found that all endophyte treatments increased soybean growth compared to control, but only in sterile soil. These results suggest context-dependency, with endophytes serving as facultative mutualists under stress or nutrient deprivation. Similarly, transcriptomic analyses revealed that soybean defense and stress responses depended on the interaction of endophytes; Methylobacterium elicited the strongest response but was modulated by the presence of Colletotrichum. Our findings highlight the environmentally dependent effects of co-existing endophytes within soybean leaves.
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- Award ID(s):
- 2022049
- PAR ID:
- 10591895
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- FEMS Microbiology Ecology
- Volume:
- 101
- Issue:
- 6
- ISSN:
- 1574-6941
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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