Piriformospora indica, a root endophytic fungus, has been shown to enhance biomass production and confer tolerance to various abiotic and biotic stresses in many plant hosts. A growth chamber experiment of soybean (Glycine max) colonized by P. indica compared to uninoculated control plants showed that the fungus significantly increased shoot dry weight, nutrient content, and rhizobial biomass. RNA-Seq analyses of root tissue showed upregulation of 61 genes and downregulation of 238 genes in colonized plants. Gene Ontology (GO) enrichment analyses demonstrated that upregulated genes were most significantly enriched in GO categories related to lignin biosynthesis and regulation of iron transport and metabolism but also mapped to categories of nutrient acquisition, hormone signaling, and response to drought stress. Metabolic pathway analysis revealed upregulation of genes within the phenylpropanoid and derivative pathways such as biosynthesis of monolignol subunits, flavonoids and flavonols (luteolin and quercetin), and iron scavenging siderophores. Highly enriched downregulated GO categories included heat shock proteins involved in response to heat, high-light intensity, hydrogen peroxide, and several related to plant defense. Overall, these results suggest that soybean maintains an association with this root endosymbiotic fungus that improves plant growth and nutrient acquisition, modulates abiotic stress, and promotes synergistic interactions with rhizobia.

No abstract

Objective:To determine the percentage of the healthy population that responds asymmetrically to the red desaturation test, and to approximate the degree of red desaturation in those individuals. We also sought to elucidate any correlation between demographic variables and red desaturation prevalence and severity.Methods:Adults aged 18 and older with a normal eye exam, including confrontation fields and best-corrected visual acuity of ≥ 20/25 OU, were eligible for this prevalence study. Those with objective or subjective afferent visual dysfunction were excluded. A total of 101 eligible participants (31.7% male; 77.2% white race; mean (SD) age: 41.5 (15.3) years) were queried whether monocular perception of redness of a standardized tropicamide bottle cap was the same and to estimate the interocular percentage difference, with one eye perceiving the bottle cap at “100% redness.”Results:Twenty-four participants (23.8%) experienced some degree of red desaturation. For these individuals with red desaturation, the average interocular difference was 9.0% (range 2-25%, 95% CI: 6.0-12.0%). There was no statistical evidence for a relationship between red desaturation and race, sex, or age.Conclusion:This study shows that nearly a quarter of healthy patients without apparent optic nerve or macular dysfunction may recognize red desaturation. This deserves consideration when interpreting red desaturation testing in patients suspected to have unilateral optic neuropathy. Further research with larger sample sizes may identify predictors of red desaturation in healthy patients, establish the red desaturation threshold separating pathologic from physiologic phenomena, and assess the repeatability of red desaturation over time in affected individuals.