Location: Small Grain and Food Crops Quality Research
Project Number: 3060-21430-009-000-D
Project Type: In-House Appropriated
Start Date: Apr 25, 2022
End Date: Apr 24, 2025
Objective:
Objective 1: Resolve the underlying changes in transcriptome and metabolome profiles, and identify regulatory genes, gene-networks and metabolic pathways responsible for wound-healing and tuber sprouting in potato during postharvest storage.
Sub-objective 1.A: Determine the effects of exogenous ethylene treatment on tuber dormancy progression and identify molecular mechanisms regulating dormancy/sprout growth by utilizing integrated transcriptome, phytohormone, and metabolome analyses.
Sub-objective 1.B: Determine the effects of exogenous DMN and CIPC treatment on tuber dormancy progression and identify genes and metabolic pathways regulating dormancy/sprout growth by utilizing integrated transcriptome, phytohormone, and metabolome analyses.
Sub-objective 1.C: Determine changes in transcriptome and metabolome profiles in tuber tissues following mechanical wounding to identify regulatory genes and metabolic pathways involved in periderm development and wound-healing processes.
Objective 2: Evaluate and report the effects of postharvest storage on intrinsic processing quality and nutritional composition of advanced breeding lines in collaboration with public breeding programs, as a USDA-ARS direct mission of research support (non-hypothesis driven).
Sub-objective 2.A: Determine cold storage (< 7°C) potential and processing characteristics of advanced breeding lines.
Sub-objective 2.B: Screen advanced potato breeding lines for vitamin C and anti-quality compounds impacting food end-use.
Approach:
Potato (Solanum tuberosum) ranks fourth among major food crops with annual global production exceeding 368 million metric tons (FAOSTATS, 2018). United States potato production exceeds 450 million hundredweight (cwt; USDA-NASS, 2018), of which 400 million cwt (~90%) with an estimated value of over $2 billion, are harvested in the fall. Because postharvest losses through physiological and disease-related processes routinely reach 10-15%, maintenance of postharvest quality is of prime concern to the potato industry. Current management strategies employed to combat these problems are several decades old and do not effectively meet today’s consumer or industry demands to control physiological deteriorations. Moreover, chemistries utilized to manage storage issues are under regulatory scrutiny and may not be available in coming years. Two physiological processes that adversely affect postharvest tuber quality are dormancy/sprouting and wound-healing. Further improvements in postharvest storage technologies are hindered by limited empirical information on biological processes underlying tuber meristem dormancy and wound-healing. Thus, the proposed research project is essential to identify the critical molecular, biochemical, and physiological mechanisms controlling tuber dormancy/sprouting and wound-healing and, ultimately, to manipulate these rate-limiting processes to reduce postharvest deteriorations of potato (Figure 1). Studies will be conducted to achieve the following objectives: (a) investigate effects of exogenous postharvest treatments (i.e., ethylene, 1,4-dimethylnaphthalene, and isopropyl-N-(3-chlorophenyl) carbamate) on tuber dormancy progression and sprouting using distinct cultivars for dormancy characteristics and utilize transcriptome and metabolome profiling to determine changes induced by these treatments, (b) identify the molecular mechanisms associated with mechanical wounding and wound-healing processes by utilizing transcriptome and metabolome profiling, and using a natural elicitor (water soluble chitosan) and distinct cultivars for periderm development and wound-healing characteristics. Equally important to the potato industry is development of superior germplasm for introducing new varieties with proven storage characteristics. Effective evaluation of new clones requires high-throughput screening facilities, specialized equipment, and resources. Therefore, we collaborate with public breeding programs to screen advanced breeding material for the postharvest storage potential, food quality and safety characteristics.
