Lab Work

Lab Snapshots!


Stress Tests!

The Stark and Dean-Coe Labs are testing how Syntrichia species respond to desiccation stress using a suite of factors such as rate of drying and duration dry.

Fig3. Left orange rapid dry
Signs of desiccation stress in Syntrichia! Few new shoots are able to sprout from this orange, rapidly-dried (<30 min) set of experimental shoots. PHOTO: L. Stark
Fig3. Right green slow dry
Slow-drying is a tolerable stress for some species of Syntrichia! Many new shoots grow from these green, slowly-dried (> 1 day to dry) experimental shoots. PHOTO: L. Stark

Ecophysiology of Syntrichia Student Training Week, July 2017

stark-lecturing-in-lab.png
PI Llo Stark giving a moss stress “chalk talk” to graduate and undergraduate students visiting from UC-Berkeley, U of Montana, and St. Mary’s College in Maryland. Experimental techniques were a key focal area to ensure that moss desiccation stress treatments and stress assessments are reproducible across labs.

Graduate and undergraduate students on the Dimensions Team gathered at UNLV’s Stark Lab to refine lab protocols for an upcoming series of ecophysiological experiments involving moss performance & stress metrics.

 

During lab training, Theresa Clark recorded videos that will demonstrate precise techniques for culturing and stress-testing mosses.

Check back soon for these instructional videos here!

 

Undergraduate student, Nora Howard worked with post-doc, Josh Greenwood and doctoral student, Caleb Caswell-Levy to refine a critical method for measuring net photosynthesis in small Syntrichia specimens using the “moss chamber”. This specialized infrared gas analyzer (IRGCA) chamber can detect fine changes in CO2 and oxygen produced by the metabolism of a moss “awakening” from desiccation dormancy!


Growing mosses…greenhouse style!

The Bowker Lab (NAU) is culturing common lichens, mosses, and cyanobacteria species from Southwest biocrust! Cultured individuals are grown under the same growth-chamber conditions, but in different combinations of diversity.  The cultured biocrust communities were planted in the field at their sites of origin and in foreign sites along an aridity gradient in Utah (reciprocal transplant experiment) to test if increasing diversity at different genetic levels (e.g. species and genotype) can increase resiliency to environmental stress! See Field Work for more pics of field transplant sites!

Fog grown cultures
Biocrust mosses (and black-colored algae) grown in culture plates at the NAU greenhouse under a continue fog regime.
Greenhouse-grown crust
Experimental units at the NAU greenhouse used to learn about the biology and ecology of biocrust species.
Cleaned for greenhouse
Dried stems of Syntrichia caninervis (left) and Syntrichis ruralis (right) cleaned and fragmented for use in greenhouse experiments.