Tindall’s first paper was accepted!

I’m pleased to announce that master’s student Tindall Ouverson’s first manuscript was accepted for publication!

Photo of woman in front of mountains

Tindall is a Master’s of Science in the Department of Land Resources and Environmental Sciences at Montana State University. Her graduate advisers are Drs. Fabian Menalled and Tim Seipel. Her research focuses on the response of soil microbial communities to cropping systems and climate change in semiarid agriculture. 

I have been mentoring Tindall as a graduate committee member since she began in fall 2019, teaching her laboratory and analytical skills in microbial ecology, DNA sequencing, and bioinformatic analysis. We first met when she came to visit when I was working in Oregon, and since then have connected remotely. She has a flair for bioinformatics analysis, and a passion for sustainable agricultural development. She plans to defend her thesis in 2021, and then to further her career in sustainable agriculture in Montana.

Tindall Ouverson, Jed Eberly, Tim Seipel, Fabian D. Menalled, Suzanne L. Ishaq. 2021. Temporal soil bacterial community responses to cropping systems and crop identity in dryland agroecosystems of the Northern Great Plains.  Frontiers in Sustainable Food Systems.  Article. Invited submission to Plant Growth-Promoting Microorganisms for Sustainable Agricultural Production  special collection.


Industrialized agriculture results in simplified landscapes where many of the regulatory ecosystem functions driven by soil biological and physicochemical characteristics have been hampered or replaced with intensive, synthetic inputs. To restore long-term agricultural sustainability and soil health, soil should function as both a resource and a complex ecosystem. In this study, we examined how cropping systems impact soil bacterial community diversity and composition, important indicators of soil ecosystem health. Soils from a representative cropping system in the semi-arid Northern Great Plains were collected in June and August of 2017 from the final phase of a five-year crop rotation managed either with chemical inputs and no-tillage, as a USDA-certified organic tillage system, or as a USDA-certified organic sheep grazing system with reduced tillage intensity. DNA was extracted and sequenced for bacteria community analysis via 16S rRNA gene sequencing. Bacterial richness and diversity decreased in all farming systems from June to August and was lowest in the chemical no-tillage system, while evenness increased over the sampling period. Crop species identity did not affect bacterial richness, diversity, or evenness. Conventional no-till, organic tilled, and organic grazed management systems resulted in dissimilar microbial communities. Overall, cropping systems and seasonal changes had a greater effect on microbial community structure and diversity than crop identity. Future research should assess how the rhizobiome responds to the specific phases of a crop rotation, as differences in bulk soil microbial communities by crop identity were not detectable.

My review on Plant-Microbial Interactions in Agriculture got published!

A few months ago, I was invited to submit an article to the special issue “Plant Probiotic Bacteria: solutions to feed the World” in AIMS Microbiology on the interactions between agricultural plants and microorganisms.  As my relevant projects are still being processed, I chose to write a review of the current literature regarding these interactions, and how they may be altered by different farming practices.  The review is available as open-access here!

“Plant-microbial interactions in agriculture and the use of farming systems to improve diversity and productivity”

A thorough understanding of the services provided by microorganisms to the agricultural ecosystem is integral to understanding how management systems can improve or deteriorate soil health and production over the long term. Yet it is hampered by the difficulty in measuring the intersection of plant, microbe, and environment, in no small part because of the situational specificity to some plant-microbial interactions, related to soil moisture, nutrient content, climate, and local diversity. Despite this, perspective on soil microbiota in agricultural settings can inform management practices to improve the sustainability of agricultural production.

Keywords bacteria; climate change; farming system; fungi; nutrient exchange; pathogens; phytohormones

Citation: Suzanne L. Ishaq. Plant-microbial interactions in agriculture and the use of farming systems to improve diversity and productivity. AIMS Microbiology, 2017, 3(2): 335-353. doi: 10.3934/microbiol.2017.2.335

I Accepted a New Position in Soil Microbiology and Agroeconomy!

As my current post-doctoral position winds down in the Yeoman Lab in the Department of Animal and Range Sciences, I am pleased to announce that I have accepted a post-doctoral position in the Menalled Lab in the Land Resources and Environmental Sciences Department! Dr. Menalled’s work focuses on agricultural weed ecology and management, particularly with respect to plant-plant interactions, changing climate (water and temperature changes), and now plant-microbe interactions!

I’ll primarily be working on a new two-year project that recently got funded through the USDA, entitled “Assessing the vulnerability and resiliency of integrated crop-livestock organic systems in water-limited environments under current and predicted climate scenarios”, but I’ll also be working collaboratively on several other similar projects in the lab.

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A little pre-job job training: I’m helping to make structures to keep rain out (rain-out shelters) of plots to simulate drier climate conditions.  Photo: Tim Seipel

My new responsibilities will include comparing agronomic performance and weed-crop-pathogen interactions between organic-tilled and organic-grazed systems, evaluating the impact of management and biophysical variables on soil microbial communities, and collaborating in modeling the long-term consequences of these interactions under current and predicted climate scenarios.  It’ll mean a lot more field work, and a lot of new skills to learn!  In fact, to help me study for my new job working with agricultural plants, my mentee and her friend made me flash cards:

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My mentee made my study cards so I could learn to identify common crop and weed species.

In addition to my new skills, I’ll be integrating my background in microbial ecology and bioinformatics, in order to study agricultural ecosystems more holistically and measure plant-microbe interactions.  In the same way that humans eat probiotics to promote a healthy gut microbiome, plants foster good relationships with specific soil microorganisms. The most exciting part is that I will act as an interdisciplinary bridge between the agroecology of the Menalled lab and the microbial ecology of the Yeoman lab, which will allow for more effective collaborations!