Selecting for Resilience in Low-input Potato Cropping Systems: Connecting Farmers and Breeders with the Genetic Resources of an Underutilized Potato Germplasm Collection

Selecting for Resilience in Low-input Potato Cropping Systems: Connecting Farmers and Breeders with the Genetic Resources of an Underutilized Potato Germplasm Collection

Summary

The goal of our organic potato research program, which began in 2007, is an integrated, participatory potato breeding, variety evaluation and seed potato production system that serves the needs of the

approximately 220 organic and low-input potato farmers in the Midwest. Modern potato varieties have been bred using conventional practices and may not be suited for organic and low input production systems. Our first objective is to evaluate 100 potato varieties for their immediate value in low-input and organic potato cropping systems, and for the resilience of their performance across multiple environments in a participatory trial. The 12 participating farmers will evaluate variety performance with guidance from

researchers, focusing on traits such as plant vigor, pest and disease resistance, yield, taste and market

appeal. Varieties will also be evaluated in disease nurseries located on University research farms for their

resistance to common potato diseases. Our second objective is to use modern genetic tools to characterize the diversity of these potato varieties to determine the potential for crop improvement through a breeding program for low-input cropping systems. Information on potato production and variety characteristics will be provided to growers and researchers through farming conferences, peer-reviewed publications, variety descriptions as Wikipedia pages, and printable fact sheets. Development of a participatory variety trialing and seed production system requires building a community. In addition to evaluating our project by its scientific output, we will evaluate it by interviewing participating farmers and undergraduate students throughout our project to identify and address challenges and opportunities that occur during this project

Objectives/Performance Targets

Objective 1: Evaluate potato varieties for their immediate value in low-input potato cropping systems, and

for the resilience of their performance across multiple environments.

In 2013, we trialed heirloom and specialty potato varieties from Seed Savers Exchange, the US Potato Genebank, and other potato collections with 26 organic farmer and gardener partners from 6 states (ND, MN, IA, WI, MI, OH). Each farm grew a subset of the 24 trial varieties plus check varieties, planting ten seedpieces of each variety. All varieties were grown at the West Madison Agricultural Research Station (WMARS) on organically managed land, and at one of two central Wisconsin organic farms with many years of potato growing expertise. Varieties were evaluated for emergence, vine vigor, pest and disease impacts, and yield and tuber quality, and several farms evaluated taste. Varieties differed for vine vigor, pest and disease impact, and tuber yield and quality. We saw site-to-site variation, attributable to differences in management and growing conditions, but some varieties were standouts at many locations. Particularly promising varieties included Early Bangor (red),Fenton Blue and Scotia Blue (purple skin and/or flesh), Gold Coin and Epicure Banana (yellow), Black Russian (fingerling), Niska and Early Epicure (white).

We produced seed potatoes for 52 varieties on organically managed WMARS land, and these will be distributed to participating farms for 2014 trials. Trials at WMARS will continue in 2014, in addition to seed potato production for 2015 trials. We continued our involvement in training a local conventional farmer in early generation seed potato production methods. He is developing his business to supply seed potatoes for specialty varieties, and plans to begin transitioning a portion of his farm to organic seed potato production in 2014. The first steps of propagation for early generation seed production for on-farm trials in 2015 were completed (seed production for on-farm trials requires at least 18 months before the trials). Finally, we continued to recruit farmers for variety trialing and have recruited at least 38 for 2014.

Objective 2: Characterize the genetic diversity of potato varieties to determine the potential for crop improvement through a breeding program for low-input cropping systems. In 2013, the undergraduate student (Axel Adams) recruited in 2012 maintained a tissue culture backup of the Seed Savers Exchange potato collection in our laboratory at UW-Madison. He grew representative plantlets for a selected subset of the collection in the greenhouse, and collected phenotypic data for 258 varieties. We screened some for virus resistance and identified a yellow skin yellow flesh variety (Aylesbury Gold) with PVY resistance. Axel optimized DNA extraction and genotyping methods for assessment of genetic diversity of this varietal subset, and will begin collecting genotypic data in spring 2014. Since Axel will be graduating in 2014, he will transfer these skills to another undergraduate student (with the assistance of Drs. Genger and Charkowski), who will complete genetic analysis of these varieties in summer and fall 2014.

Accomplishments/Milestones

In 2012, we produced enough seed potatoes from 57 lines for field trials in 2013. Of these, we have

enough seed from 28 lines for on-farm trials. The remaining lines will be assessed on a university research farm and the harvested potatoes will be stored for trials in 2014. Seed potatoes will be produced from additional lines that are currently only available as tissue culture plantlets in 2013.

We also obtained the plant material and identified a student for completion of Objective Two.

Impacts and Contributions/Outcomes

In the past year, the impacts of this project include:

1.      outreach visits to participating farms in WI, MN and ND, including educational presentations to participating and interested farmers and students;
2.      a presentation at the WMARS organic field day (approximately 150 participants);
3.      a poster presentation and round-table discussion with farmers at the MOSES Organic Farm conferences (Feb 2014);
4.      continued training of a Wisconsin conventional farmer interested in organic seed potato production;
5.      continued development of a website and blog for disseminating information about our project (organicpotato.wisc.edu).

Collaborators: