Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

View full-text article in PMC

. 2017 Oct 18;7:13479. doi: 10.1038/s41598-017-14080-x

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

© The Author(s) 2017

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.

PMC Copyright notice

Testing endophyte 3F11 for its ability to cause ambient acidification using bromocresol purple as a pH indicator. A change in color from purple to yellow indicates a decline in pH. (A) Test for in vitro acid production by a representative colony of 3F11 using NBRIP agar after 24 h compared to a negative control endophyte, 3F7. (B,C) Test for in planta acid production of 3F11 following seed inoculation of annual ryegrass. Shown are three 3F11-inoculated roots (left) or uninoculated roots (right) placed on insoluble-P agar medium (NBRIP) supplemented with bromocresol purple and either (B) no kanamycin or (C) kanamycin. The growth of 3F11 but not annual ryegrass was previously shown to be suppressed by kanamycin. (D) Confirming the colonization of GFP-tagged 3F11 cells on annual ryegrass roots on an LB agar plate following coating onto seeds. (E,F) Testing the co-localization of 3F11 cells with acid production in planta. Shown are three GFP-3F11-inoculated roots (left) or uninoculated roots (right) placed on insoluble-P agar medium (NBRIP) supplemented with bromocresol purple and kanamycin and (E) imaged using UV light to reveal GFP or (F) white light to reveal acid production (yellow). (G,H) Test for the effect of P-bioavailability in the rhizosphere on the in planta acid production of 3F11. Shown are three GFP-3F11-inoculated roots (left) or uninoculated roots (right) placed on (G) soluble-P agar medium supplemented with bromocresol purple and (H) insoluble P containing agar medium (NBRIP) supplemented with bromocresol purple. (I,J) Representative confocal microscopy images showing colonization of GFP-tagged 3F11 cells on annual ryegrass root systems 7 days following seed-inoculation and growth on either (I) rock P, or (J) soluble P, showing the difference in the extent of colonization.