Skip to main content
ARS Home » Plains Area » Fargo, North Dakota » Edward T. Schafer Agricultural Research Center » Sugarbeet and Potato Research » Research » Research Project #425284

Research Project: Physiological and Genetic Approaches to Improving Extractable Sugar Yield in Sugarbeet

Location: Sugarbeet and Potato Research

2018 Annual Report

Objective 1: Identify physiological approaches for reducing sucrose loss due to storage rot and environmental stresses, including cold, drought, and soil salinity, using plant inducible defenses. Subobjective 1a: Determine the ability of jasmonic acid (JA) and salicylic acid (SA) to reduce the incidence and severity of storage rot due to Botrytis cinerea, Fusarium graminearum, Penicillium claviforme, and Phoma betae. Subobjective 1b: Determine the ability of jasmonic acid and salicylic acid to mitigate the impact of environmental stress caused by limited water availability, cold temperature, or high soil salinity. Subobjective 1c: Identify JA- and SA-induced biochemical and molecular changes associated with the induction of native defense responses by characterizing enzymes and gene products implicated in inducible defense responses via global transcriptional analysis. Objective 2: Identify the physiological mechanisms that regulate sugarbeet root respiration and resultant sucrose loss, and characterize the impact of Rhizoctonia root rot and leaf regrowth on sucrose loss during root storage in order to optimize storage management practices. Subobjective 2a: Identify enzymatic reactions and metabolic intermediates in sucrose catabolic pathways that may restrict root respiration rate. Subobjective 2b: Determine the effects of Rhizoctonia root and crown rot on root storage properties in relation to disease severity and duration of storage. Subobjective 2c: Determine the effect of postharvest leaf regrowth on sugarbeet root respiration and the effect of storage temperature on leaf regrowth. Objective 3: Characterize the root impurity components that interfere with sucrose extraction during processing, and develop germplasm with reduced concentrations of these compounds. Objective 4: Enhance the genetic diversity of breeding gene pools and breed genetically diverse sugarbeet lines with improved sugarbeet root maggot resistance. Subobjective 4a: Enhance the genetic diversity of breeding gene pools through introgression of exotic germplasm. Subobjective 4b: Through traditional breeding approaches, develop improved sugarbeet root maggot resistant germplasm.

The U.S. sugarbeet industry produces 60% of domestically grown sugar and nearly half of domestically consumed sugar. Thirty-two million tons of sugarbeet roots, valued at 2.1 billion dollars, are produced annually. The sugarbeet industry faces intense competition from alternative sweeteners and escalating production costs. For the industry to remain viable and to ensure a reliable, domestic supply of a staple in the American diet, increases in net productivity are essential. The yield of sugar produced after processing, or the extractable sucrose yield, determines net productivity for the sugarbeet crop. This yield depends on biomass and sucrose accumulation during production, sucrose retention during postharvest storage, and sucrose recovery during processing. The goal of research proposed in this project is to increase sugarbeet extractable sucrose yield by generating information and genetic resources that will lead to new production and storage protocols and improved hybrids for enhanced sucrose yield at harvest, improved sucrose retention during storage, and increased sucrose recovery during processing. Specific goals are to (1) determine the potential of inducible defense responses to reduce yield losses due to environmental stresses and storage rots, (2) determine the endogenous mechanisms that regulate root respiration during storage, (3) characterize the impact of Rhizoctonia root and crown rot and leaf regrowth on postharvest losses, (4) develop germplasm that facilitates improvements in processing quality, (5) develop germplasm that broadens the genetic base of sugarbeet, and (6) develop germplasm that combines high levels of sugarbeet root maggot resistance with resistance to prevalent diseases and improved sucrose concentration.

Progress Report
This is the final report for project 3060-21000-040-00D. Work will continue under project 3060-21000-044-00D, “Increasing Sugar Beet Productivity and Sustainability through Genetic and Physiological Approaches”. Over the five year life of the project, research was conducted that successively met all objectives of the Project Plan and generated information and genetic resources to support sugarbeet industry efforts to increase net productivity of the crop. Research demonstrated that postharvest application of the plant hormone jasmonic acid (JA) effectively reduces sugarbeet storage rot due to three common pathogens. Applied after harvest, JA reduced rot due to Botrytis cinerea, Penicillium claviforme, and Phoma betae by 51, 44, and 71%, respectively. Application of another plant hormone, salicylic acid, halved losses to storage rots in roots harvested from drought-stressed plants. Together, these findings provide two inexpensive and nontoxic methods to reduce storage losses to disease. Additionally, application of methyl jasmonate (MeJA), a natural derivative of JA, was shown to alleviate drought stress in young sugarbeet plants by reducing drought-induced declines in photosynthesis and delaying plant dehydration relative to controls. The demonstrated ability of MeJA to alleviate water stress provides growers a new management tool to reduce losses due to dry conditions during early crop production. Research was also conducted to determine the effect of JA and MeJA on gene expression to understand how these compounds reduce sugarbeet storage rot and drought stress. This study identified 588 genes that were altered in expression by JA treatment, including 88 genes involved in plant defense. Since sugarbeet roots respire during storage via a metabolic process that consumes the sucrose stored in the root, research was conducted to understand the internal mechanisms that regulate sugarbeet root respiration rate. This research revealed a close relationship between storage respiration rate and glycolysis—the metabolic process that degrades sugars to produce substrates for respiration--indicating that the generation of respiratory substrates by glycolysis is likely to have a significant role in controlling storage respiration rate. Additionally, two glycolysis pathway enzymes, pyruvate kinase and phosphofructokinase, were indicated to have major roles in regulating glycolysis. During sugarbeet root processing, sodium, potassium and amino-nitrogen, collectively known as impurity components, prevent the recovery of a portion of the sugar in sugarbeet roots. Genetic stocks selected for low concentrations of each of the individual impurity components were used to determine relationships among impurity components and the effect of selecting for a single impurity on sucrose concentration and sucrose extraction rate. Research demonstrated that the probability of significant improvement in the processing quality of roots by reducing the concentration of an individual impurity component is low. The effect of disease severity due to Rhizoctonia crown and root rot (RCRR) on sugarbeet root storage was determined to generate guidelines that can be used by the industry for managing storage of roots with this disease. Research related RCRR disease rating with deterioration in storage. This research revealed that root storability was minimally affected by minor symptoms of RCRR, but deteriorated rapidly with increased disease severity. During the five years spanned by this project, 24 germplasm lines were released and placed in the USDA-ARS plant germplasm system where they are freely available for distribution to other researchers and commercial seed companies. One of these 24 lines has resistance to the sugarbeet root maggot, a major insect pest of sugarbeet in North America. Resistance was derived from an accession originally collected in Turkey in 1948. The remaining 23 germplasm lines were selected from populations formed by crossing cultivated sugarbeet with beet wild relatives collected along the coasts of England, Wales, France, Belgium, Denmark, and the Channel Islands. The infusion of genes from these and other exotic sources into elite breeding populations has the potential to expand the limits of improvement through selection and produce parental lines with enhanced combining ability.

1. Application of natural plant hormone alleviates drought stress in sugarbeet. Drought is a major cause of yield and economic loss for the sugarbeet crop and is most damaging when it occurs during early crop development. Mechanisms to reduce drought stress during sugarbeet production, however, are unavailable since sugarbeet is predominantly grown without irrigation and drought-tolerant varieties are not available. Since the natural plant hormone, methyl jasmonate (MeJA), is involved in plant drought-stress responses, ARS researchers in Fargo, North Dakota conducted research to determine whether exogenous application of MeJA could reduce drought effects on young sugarbeet plants. Applied prior to drought, MeJA successfully delayed plant dehydration, mitigated drought-induced reductions in photosynthesis, and protected the collection of proteins within leaves that are responsible for carrying out photosynthesis from drought-induced damage. The research established that application of MeJA effectively alleviates drought stress on young sugarbeets and provides sugarbeet growers a new management tool to reduce economic losses due to dry conditions during early crop production.

Review Publications
Campbell, L.G. 2017. Sugarbeet root maggot from a red globe-shaped beet (PI 179180). Journal of Sugar Beet Research. 54(1-2):50-59.
Campbell, L.G., Fugate, K.K. 2017. Sugarbeet germplasm lines selected from crosses between cultivated sugarbeet and wild Beta vulgaris subsp. maritima from the United Kingdom. Journal of Sugar Beet Research. 54(1-2):20-34.
Nibert, M.L., Vong, M., Fugate, K.K., Debat, H.J. 2018. Evidence for contemporary plant mitoviruses. Virology. 518:14-24.
Fugate, K.K., Lafta, A.M., Eide, J.D., Li, G., Lulai, E.C., Young, L.L., Deckard, E.L., Khan, M.F., Finger, F.L. 2018. Methyl jasmonate alleviates drought stress in young sugarbeet (Beta vulgaris L.) plants. Journal of Agronomy and Crop Science.
Prasifka, J.R., Mallinger, R.E., Portlas, Z.M., Hulke, B.S., Fugate, K.K., Paradis, T., Hampton, M.E., Carter, C.J. 2018. Using nectar-related traits to enhance crop-pollinator interactions. Frontiers in Plant Science.
Lopez-Teros, V., Ford, J., Green, M., Tang, G., Grusak, M.A., Quihui-Cota, L., Muzhingi, T., Paz-Cassini, M., Astiazaran-Garcia, H. 2017. Use of a ‘Super-child’ approach to assess the Vitamin A equivalence of Moringa oleifera leaves, develop a compartmental model for Vitamin A kinetics, and estimate Vitamin A total body stores in young Mexican children. Journal of Nutrition. 147:2356-2363.
Katuuramu, D.N., Hart, J.P., Porch, T.G., Grusak, M.A., Cichy, K.A. 2018. Genome-wide association study for nutritional composition traits in cooked common bean seeds. Molecular Breeding. 38:44.
Reig, G., Lordan, J., Fazio, G., Grusak, M.A., Hoying, S., Cheng, L., Francescatto, P., Robinson, T. 2018. Horticultural performance and elemental concentration of 'Fuji' grafted on Geneva apple rootstocks under New York climatic conditions. Scientia Horticulturae. 227:22-37.
McClean, P., Moghaddam, S.M., Lopez-Millan, A., Brick, M., Kelly, J., Miklas, P.N., Osorno, J., Porch, T.G., Urrea, C., Soltani, A., Grusak, M.A. 2017. Phenotypic diversity for seed mineral concentration in North American dry bean (Phaseolus vulgaris L.) germplasm of Middle American ancestry. Crop Science. 57:3129-3144.
Qin, J., Shi, A., Mou, B., Grusak, M.A., Weng, Y., Ravelombola, W., Bhattarai, G., Dong, L., Yang, W. 2017. Genetic diversity and association mapping of mineral element concentrations in spinach leaves. BMC Genomics. 18:941.
Vandemark, G.J., Grusak, M.A., McGee, R.J. 2018. Mineral concentrations of chickpea and lentil cultivars and breeding lines grown in the U.S. Pacific Northwest. The Crop Journal. 6:253-262.
Fazio, G., Grusak, M.A., Robinson, T. 2017. Apple rootstocks' dwarfing loci relationships with mineral nutrient concentration in scion leaves and fruit. Acta Horticulturae. 1177:93-102.
Hadsell, D.L., Hadsell, L.A., Rijnkels, M., Carcamo-Bahena, Y., Wei, J., Williamson, P., Grusak, M.A. 2018. In silico mapping of quantitative trait loci (QTL) regulating the milk ionome in mice identifies a milk iron locus on chromosome 1. Mammalian Genome.