We were fortunate enough to have a high school student from the North Carolina School of Science and Mathematics volunteer in our lab at NC State. She designed two experiments to help us understand how the fungus causing mangrove lesions interacts with salt, one of the abiotic stressors we think likely contributed to the mangrove die-off.
First, she tested if growth of the fungus differed at all on agar media with added salt. She found that growth was essentially the same on salty media and unsalted media. This suggests that this fungus does not have a problem growing on salty things, like mangrove leaves!
Second, she tested if mangrove leaves that were exposed to salt water would have more lesions develop when inoculated with the fungus. She found that leaves exposed to saltier water and the fungus did indeed develop more lesions than leaves that were just exposed to freshwater and the fungus. This experiment supports our idea that salinity may have been one of the initial stressors the mangroves were subjected to in the die-off area.
Thanks for all of your hard work, Sophie!