Agricultural Sustainability in the Local Context
Open Access
- Author:
- Paukett, Michelle
- Graduate Program:
- Plant Pathology (PHD)
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- December 08, 2023
- Committee Members:
- Sharifa Crandall, Major Field Member
Alyssa Anne Collins, Special Member
Maria Del Mar Jimenez Gasco, Program Head/Chair
John Pecchia, Major Field Member
Paul Esker, Chair & Dissertation Advisor
Charlie White, Outside Unit & Field Member - Keywords:
- Mortierella spp.
sustainable agriculture
soil microbiome
content analysis
Fusarium solani
on-farm networks
soybean
biocontrol
local knowledge
disease-suppressive soils - Abstract:
- In 2015, the 2nd Sustainable Development Goal of the United Nations was created as a global commitment to enhancing agricultural sustainability to adapt to diverse challenges, from food security to climate change. This dissertation aims to understand how commodity organizations and microorganisms facilitate sustainable agriculture transformation in local contexts. Starting at the macro-level, the framing of sustainability by producer-led commodity organizations with on-farm research initiatives is evaluated using content analysis of stakeholder newsletters and Facebook communications to characterize how they support the environmental, economic, and social dimensions of sustainability in their local production contexts. By comparing the Pennsylvania Soybean Board and the Corporación Arrocera Nacional (Conarroz), in the USA and Costa Rica, respectively, universal and spatiotemporal-unique contributions to sustainability are identified. These organizations demonstrated adaptability to challenges through advocacy, research, and education, driving the development of long-term sustainable agricultural infrastructure within their local contexts. Future work can expand the analysis to evaluate these organizations' bi-directional communication of sustainable initiatives to promote stakeholder adoption of sustainability practices, enhancing all three dimensions. At the soil microbiome community level, the value of local knowledge of soil abiotic and biotic properties was demonstrated through greenhouse, growth room, and field experiments focused on how plant health is influenced by bacterial and fungal abundance and diversity during early soybean development under Pythium disease pressure and different soil conditions relevant to Pennsylvania soybean producers. The microbiome did not dramatically shift to reduce disease severity during the two-week period, suggesting that sustainable management decisions for early-season diseases can be based on the soil microbiome abiotic and biotic composition at planting. Future work can capture microbiome community shifts at each growth stage that correspond to disease outcomes throughout the growing season and characterizing a Pythium species-suppressive starting soil microbiome. Lastly, at the fungal genus level, the biocontrol potential of Mortierella spp. obtained from Pennsylvania soils was tested against the soybean root rot pathogen Fusarium solani using a series of plate-based laboratory experiments. Isolates were found to inhibit F. solani growth between 18% to 52% and highly inhibitory isolates were identified across species. This project also highlighted that Mortierella species distribution in PA soybean fields is not strongly driven by environmental factors and species grow competitively at a wide temperature range, making future work developing a biocontrol product from highly inhibitory Mortierella spp. isolates for long-term sustainable soilborne disease management relevant to soybean growers across Pennsylvania. Altogether, these projects support the use of local knowledge in achieving the second Sustainable Development Goal of promoting sustainable agriculture, increasing agricultural productivity and farmer incomes, and ensuring agricultural systems are adaptable to current and future challenges.