10:15am-10:45am
Revolutionizing Potato Breeding with Foodomics: A Path to Improved Human and Planetary Health
Sahar Toulabi, Colorado State University

               "One of the emerging challenges of our century is food insecurity, correlated with a rise in obesity and associated disorders such as chronic diseases. Greater than half of the U.S. population (3 out of 4) are at risk of developing chronic diseases,3. However, access to nutritious, affordable, and desirable foods continues to be a challenge4. This emphasizes the need to investigate and encourage health-promoting traits of the most affordable and highly consumed commodities, such as potatoes, to support a sustainable and healthy food supply for the broader population5,6.  We utilized the global Periodic Table of Food Initiative (PTFI) to investigate a) the chemical composition of various potato cultivars and b) the effect of processing on their nutritional value. PTFI is a global foodomics ecosystem of standardized metabolomics methods to measure the chemical composition of crops. Additionally, a high phenolic potato (PP) diet was evaluated for its health outcome in obese and lean animal models. PP diet resulted in lower food intake, adiposity, and body weight among obese and lean animals. A non-targeted metabolite profiling approach (LC-MS and GC-MS) showed a clear separation of overall metabolites between obese and lean animals and based on their respective diets (PP vs Control). Notably, both serum and liver detected potato’s phytochemicals with anti-inflammatory potential. Beyond metabolite changes, we observed decreased circulating inflammatory cytokines (Monocyte Chemoattractant Protein-1). We also observed favorable trends in anti-inflammatory T cell increases within the perivascular adipose tissue (PVAT). This study reveals the potential of various potato cultivars as valuable assets for enhancing human health. It also sheds light on the pressing issue of malnutrition and underscores the importance of integrating foodomics with breeding efforts to unlock more excellent nutritional value from the vast genetic diversity within the potato gene pool."

10:45am-11:00am       
Natural Elicitors Enhanced Wound Healing of Potato Tubers
Dipayan Sarkar , USDA Agricultural Research Service

               Wounding affects the overall quality and marketability of potato tubers and can occur unintentionally during harvest or postharvest handling, or intentionally due to the common practice of cutting seed tubers before planting. In either case, rapid healing of wounded or cut surfaces is important for protecting tubers against pathogens and physical decay. Therefore, finding safe and effective wound-healing (WH) treatment strategy is essential for economic sustainability of potato industry. The objective of this study was to investigate the efficacy of two natural elicitors, chitosan oligosaccharide (COS 0.125 g L-1) and cranberry pomace residue (Nutri-Cran 0.125 g L-1) for improving WH of five red-skin potato cultivars (Chieftain, Dakota Rose, Dakota Ruby, Red LaSoda, Red Norland). Formation of suberin polyphenolics (SPP), was determined histologically at 0, 3, 6, and 9 days after wounding. The potential role of stress protective metabolic regulation related to phenolic metabolites, proline, and antioxidant enzymes were also determined. Our results indicated that both COS and Nutri-Cran accelerated formation of SPP in wounded tissue surface. The elicitor treatments also enhanced ferulic and chlorogenic acid content, which are related to the SPP domain. Higher activities of total antioxidant and superoxide dismutase were also detected with elicitor treatments. Additionally, reduced activity of succinate dehydrogenase, an indicator of respiration rate, was observed with Nutri-Cran treatment in Red Norland and Dakota Ruby after 3 days of wounding. Faster healing of tissues was observed in Chieftain and Red Norland tubers. Collectively, these results suggest that Nutri-Cran induces stress protective responses and accelerates formation of SPP at wounded surface, while suppressing respiration during WH of potato tuber tissues. Overall, Nutri-Cran is a promising WH treatment option and can be optimized for commercial use in postharvest storage to mitigate wounding and bruising related potato tuber losses.

11:00am-11:15am
Maximising seed efficiency using ethylene and temperature
Paul Coleman, Restrain Company Limited

               "Seed potato production is severely limited by the number of lateral buds that develop and grow as mainstems using conventional seed management techniques. Variety, apical dominance and seed age all impact stem and progeny tuber number. The physical cutting of seed is the traditional approach to unlocking apical dominance and improving efficiency of  seed production, but comes with significant risk to crop health and tuber size variation. Ethylene (C2H4 ) offers an additional tool to further increase production efficiency with and without cutting. Ethylene is a natural, gaseous plant hormone that plays many roles in plant biochemical pathways. Many are familiar with the role of ethylene in fruit ripening but also leaf and petal fall as well as restricting cell elongation in potatoes and alliums (onions). In respect to seed potatoes ethylene has the benefit of blocking auxin production, responsible for apical dominance of sprouts. Restrain’s ethylene has a recent registration approval in the USA and Canada for the treatment of seed potatoes. Over the last 25 years in the UK and Europe, Restrain has developed an ethylene and storage temperature management process, “Accumulator” , that significantly increases lateral bud development resulting in 20-50% more stems compared to 38F stored seed, resulting in typically 20-30% more tubers. In the presentation we explore the impacts of the period of ethylene treatment (days in store), storage temperatures and variety interaction. With circa 70,000 tonnes of seed potatoes treated annually in Europe and the UK, large processors are now moving to the use of Accumulator to improve maincrop production efficiency and reduce costs. In the USA, a two year trial is underway with Washington State University and University of Idaho. Three varieties are being examined and will be planted as whole seed and cut seed. Provisional results will be presented. "

11:15am-11:30am
Postharvest Storage Conditions Impact Potato Tuber Microbiome and Dormancy Progression
Evandro Fortini , USDA - Agricultural Research Service

               Microbes are integral part of agricultural ecosystem and contribute to plant growth and performance as well as postharvest storage and nutritional qualities of crops. Potato tubers are stored in a fully hydrated form, with a minimal cleaning after harvest, carrying a layer of microbiome from field to storage. Impact of plant microbiome on postharvest storage quality of potatoes are mainly unexplored. The objective of this study is to investigate the effects of different storage temperatures on the potato tuber microbiome and dormancy progression. After harvest, certified seed tubers of Russet Burbank were cured and one subset of tubers was stored at constant 8°C, a second subset was stored at constant 21°C. Tuber tissues (primary meristem, secondary meristem, tuber flesh) were collected after 4, 8, 12, 17, and 24 weeks of storage for microbiome profiling and sugar analysis. Additionally, a third subset was generated by moving tubers from 8°C to 21°C three days before sampling time of 8, 12, and 17 weeks. Sprout growth was monitored weekly to determine tuber dormancy progression. As expected, delayed sprouting was observed in tubers stored at 8°C, while tubers stored at 21°C broke dormancy five weeks earlier. Meristem tissues exhibited significantly higher fungal and bacterial diversities compared to the tuber flesh. Furthermore, bacterial and fungal communities were significantly influenced by storage temperature, tissue types and storage period. The fungal phyla were dominated by Ascomycota and Basidiomycota, while Actinobacteria, Proteobacteria, and Cyanobacteria were the most dominant bacterial phyla. Throughout the storage time, glucose and fructose contents increased in primary and secondary meristems but decreased in tuber flesh. Overall, our findings highlight how different storage conditions, such as temperature and storage duration, impact dormancy progression and alter tuber microbiome in different tuber tissues.

11:30am-11:45am
Analysis of glycoalkaloid metabolism in potatoes
Roy Navarre, USDA

               Various environmental factors can increase the amount of glycoalkaloids in tubers with light being the best understood. Light-induced accumulation of SGA and concurrent greening tubers is a major problem that in severe cases has caused up to 15% - 17% of the crop to be culled. Transcriptomic and metabolomic approaches were applied to monitor levels of SGA, chlorophyll (CHL), and carotenoid (CAR), and 35 target genes (SGA and CHL associated genes) in potatoes exposed to light. Levels of SGA were markedly spiked in 8 white and 2 color flesh genotypes among the 20 studied (10 white and 10 color), exceeding the accepted limit of 20 mg/100 g FW. Other genotypes had less spiking of SGA. Following 8 months storage at 7 °C the levels of CHL response to light decreased, whereas the level of SGA increased in the dark. Metabolic analysis across different genotypes showed color potato with higher amounts of CAR had less SGA spiking and revealed a possible mechanism of isoprenoid intermediates exchange between the cytosol and the plastid. In addition, isoprenoid metabolism was altered by overexpressing or suppressing HMGR in transgenic plants and the effect on SGA, CHL and CAR evaluated. These findings provide insights into mechanisms that control levels of SGA.

11:45am-12:00pm
Determination of biochemical factors contributing to French fry texture and quality
Sastry Jayanty, Colorado State University

               Human consumption of potatoes (Solanum tuberosum L.) is dominated by processed products such as frozen French fries, chips, and other processed foods worldwide. Nearly one-third of the US potato production is processed into par-fried frozen potatoes or fried chips. The highest-quality French fries are made from a few select potato cultivars. Our goal is to develop biochemical and molecular markers to screen cultivars with the best processing quality for French fries. Our investigation is focused on possible factors that contribute to texture quality. This study was conducted using twelve cultivars grown in two states (Washington and Idaho). We compared the composition of cell wall metabolites and starch, the levels of texture-associated enzymes, and the structural changes that occurred at different stages of the French fry processing using scanning electron microscopy. Differential scanning calorimetry is being used to examine the gelatinization and heat holding capacity of starch granules at different stages of French fry processing. We will discuss the results on how starch quality might play a role in the variation of French fry texture quality in different cultivars.