Volume 60, Number 1, April 2023

Drought is one of the main constraints in sugar beet cultivation. Empirical studies and model simulations demonstrated yield reductions up to 40%, resulting in a significant financial impact on the beet sugar industry. The impact of water shortage is expected to aggravate in the future, as the frequency and intensity of drought spells are expected to increase with climate change. Therefore, yield stability under water-deficit conditions is becoming a crucial trait in sugar beet breeding. By combining continuous environmental and satellite data we aim to classify sugar beet growing environments along different drought intensities. Based on these classifications, genetic diversity in drought tolerance across multi-location trial networks can be assessed. Furthermore, we discuss the possibilities and the approach that we employ for further variety improvement for drought tolerance.

Precipitated calcium carbonate lime is a byproduct of sucrose extraction at sugarbeet processing factories in Idaho. Each year 351,000 Mg of this lime is produced and stockpiled at sugarbeet factories. There is currently no viable disposal strategy for this material and these piles continue to grow in size each year. The simplest solution would be to apply this PCC directly to agricultural fields each year, however the effects of PCC on high pH soils and southern Idaho crop rotations are not well understood. Due to high amounts of lime production (351,000 Mg year^-1), dA study was conducted at the USDA-ARS laboratory in Kimberly, ID to determine the effects of PCC application to an alkaline silt loam soil on sugarbeet, dry bean and barley production and soil properties. Three PCC treatments (rate and timing) and an untreated control were compared. The PCC had no effects on crop production factors and most soil properties. The only significant effect of PCC treatments was an increase in soil phosphorus (P) concentrations compared to the control. The PCC can serve as a P fertilizer. For all crops in this study, PCC was applied at rates that resulted in applied P levels that were 1.6 to 5.3 times greater than even the highest published recommended P rates. Compared to the control, bicarbonate soil P concentrations increased by 25% and 73% for the final PCC application amounts of 26.9 kg ha^-1 (6.7A treatment) and 89.7 kg ha^-1 (6.7A and 89.7T treatments), respectively. The PCC used in this study can safely be applied (at rates up to 87.9 kg ha^-1) to heavier textured alkaline soils in the local growing area. Disposing of PCC in this way is a viable strategy for reducing PCC stockpiles.

Precipitated calcium carbonate lime is a byproduct of sucrose extraction at sugarbeet processing factories in Idaho. Each year 351,000 Mg of this lime is produced and stockpiled at sugarbeet factories. There is currently no viable disposal strategy for this material and these piles continue to grow in size each year. However, with an average total P content in PCC of 150 kg P₂O₅/Mg and high fertilizer P prices, the application of PCC as a P source can be a practical alternative to fertilizers.

Glyphosate-resistant waterhemp is quickly becoming one of the most difficult weeds to manage in sugarbeet. Extended emergence, rapid growth rates, and the lack of postemergence herbicide options necessitate the use of creative options to manage waterhemp. Over the past six years we have examined various strategies and tested various herbicides for waterhemp control and sugarbeet tolerance. Acifluorfen (Ultra Blazer), phenmedipham (Spin-Aid), phenmedipham + desmedipham (Betamix), and the residual herbicides metamitron, ethofumesate and several Group 15 herbicides have all been components of this research. To date, the most consistent waterhemp control includes the use of a preemergence herbicide either ethofumesate (1.12 kg ha^-1) or s-metolachlor (0.53 kg ha^-1) followed by one of the overlapping herbicide programs of two applications of: 1) s-metolachlor (Dual Magnum) at 1.06 kg ha^-1, 2) acetochlor (Warrant) at 1.26 kg ha^-1, or 3) dimethenamid-P (Outlook) at 0.56 kg ha^-1 applied at 2- and 6-8 leaf sugarbeet. In most cases, these programs also did not significantly influence sugarbeet yield. It is important to remember that the residual herbicide will not control emerged waterhemp. This is where understanding the time of waterhemp emergence in relation to sugarbeet planting is important. Most of Michigan’s waterhemp populations start to emerge the 3^rd or 4^th week of May. The first application of a residual herbicide would need to be applied prior to waterhemp emergence. If sugarbeets are planted later, the use of a preemergence herbicide would be needed.

Nutrient management strategies have always been a focal point of sugarbeet production. However, with the adoption of the 30-300 Initiative (i.e., 30 T A^-1 and 300 lbs sugar T^-1), Michigan sugarbeet production continues to emphasize improving beet quality as compared to yield. New obstacles continue to impact agronomic management including a more variable climate, early harvest intervals, updated varietal characteristics, and managing an N-responsive cropping system that growers may or may not wish to respond to N applications. Although management has mostly evolved to being site- or field-specific, little work has been done investigating how nutrient management may change based on sugarbeet varietal characteristics. More defensive varieties with greater disease tolerance may respond differently compared to more aggressive varieties with greater tonnage. Field studies were established to evaluate sugarbeet varietal response (defensive vs. aggressive) to specific fertilizer management strategies and early vs. conventional harvest intervals. The study was blocked by two harvest timings (early and conventional) and two varieties (C-G675 and C-G919). All treatments received 60 lb. N A^-1 at planting applied 2×2. Four fertilizer strategies consisted of only 60 lb. N A^-1  applied 2×2 at-plant, 60 lb. N A^-1  applied 2×2 and 100 lbs. N A^-1 sidedress coulter inject at 4-leaf stage, 60 lb. N A^-1  applied 2×2 and 100 lbs. K₂O A^-1 surface applied next to row at canopy closure (~20 leaf stage), and 60 lb. N A^-1  applied 2×2 along with 100 lbs. N A^-1 sidedress coulter inject at 4-leaf stage and 100 lbs. K₂O A^-1 surface applied next to row at canopy closure (~20 leaf stage). Climate variability continued to impact growth and production in 2021 with moist autumn conditions decreasing sugar concentrations by 0.37% in October harvest as compared to August. Despite a mean yield increase of 16 T A^-1 with conventional as compared to early harvest, no interaction between variety and harvest timing occurred in 2021. Starter N was sufficient for early harvest specifically in 2021 with no tonnage differences observed compared to starter with sidedress N. Field results from 2022 will be included after harvest is complete and compared alongside 2021 field data.

Every year a portion of Alberta growers apply urea nitrogen fertilizer in spring prior to seeding sugar beets. Twenty-two separate trials over a 5-year period between 2015 and 2020 were conducted to assess the potential for sugar beet stand loss when urea is soil incorporated prior to planting and irrigated prior to sugar beet emergence. In addition, nine separate trials were conducted between 2015 and 2021 to assess the potential for sugar beet stand loss when urea is surface applied and irrigated after planting but prior to emergence. Urea rates up to 200 lbs N/acre were applied in all trials, with the 200 lb rate being used to accentuate and differentiate treatment effects. When urea was soil incorporated, highly significant (p<0.01) sugar beet stand reductions averaging 28% were observed with applications of 200 lbs N/acre urea in 6 tests where a single irrigation ≤0.5 inch was applied. Where a single irrigation ≥0.6 inch was applied, sugar beet stand reductions with 200 lbs N/acre averaged 11% and were only significant (p<0.05) in 2 of 6 trials. Stand reductions with 100 lb N/acre soil incorporated urea averaged 12% and were significant (p<0.05 and p<0.01) in 4 of 6 trials where a single irrigation of ≤0.5 inch was applied. When a single irrigation ≥0.6 inch was applied, sugar beet stand reductions with 100 lbs N/acre averaged 2% and were not significant in any trials. Results were similar for single and multiple irrigations with 100 and 200 lbs N/acre soil incorporated applications. When urea was surface applied and irrigated prior to sugar beet emergence, sugar beet stand reduction ranged from 2 to 98% with applications of 200 lbs N/acre, with higher stand reductions observed for lower irrigation plus rainfall volumes. Results from these trials show that greater amounts of applied water can mitigate the toxic effects of spring urea applications. Many Alberta growers use lower irrigation volumes when watering for sugar beet emergence. When spring urea is incorporated at 100 lbs N/acre with current watering practices, a sugar beet stand loss in the order of 12% could be expected.

Glyphosate resistant (GR) common ragweed (Ambrosia artimisiifolia), kochia (Bassia scoparia), and waterhemp (Amaranthus tuberculatus) are weed control challenges in sugarbeet. Sugarbeet producers control GR common ragweed with clopyralid at rates ranging from 53 to 105 g ha^-1 and GR waterhemp using soil residual herbicides applied after planting or between 2-lf and 8-lf sugarbeet stage. Timely rainfall to incorporate soil residual herbicides was absent in 2021 and 2022, complicating waterhemp control. GR kochia control in sugarbeet is best when effective herbicides are used in the crop sequence preceding sugarbeet. Ethofumesate is the most reliable sugarbeet herbicide for kochia control but is dependent on rainfall for incorporation. Dicamba and glufosinate integrated into the weed control program with Truvera® sugarbeet will benefit sugarbeet producers. Field experiments were conducted in Minnesota and North Dakota in 2021 and 2022 to evaluate sugarbeet tolerance and to redefine a weed control program to control GR weeds. In tolerance experiments, dicamba at 0.56 kg ha^-1 plus a volatility reduction adjuvant and a drift reduction agent at 1.46 L ha^-1 and 0.5% v/v, respectively, at 2- to 4-lf sugarbeet caused stature reduction injury 1 to 7 and 8 to 14 days after application as compared with the glyphosate control in 2021. However, sugarbeet injury was negligible from dicamba 15 or more days after application or from glufosinate at 0.62 kg ha^-1 across application timing. Root yield from dicamba applied at the 10- to 12-lf stage was less than root yield from the glyphosate control or from dicamba PRE, dicamba at the 2- to 4-lf or the 6- to 8-lf stage and from glufosinate at the 2- to 4-, 6- to 8 or 10- to 12-lf stage. Dicamba or glufosinate did not affect percent sucrose compared with the glyphosate control. Dicamba alone or dicamba mixed with ethofumesate PRE controlled early emerging waterhemp better than and dicamba and glufosinate with glyphosate, and chloroacetamide herbicide(s) provided season long waterhemp control better than our best currently commercialized waterhemp control programs in 2021 and 2022. Treatments combining repeat clopyralid applications at 79 g ha^-1 with glufosinate or glyphosate or dicamba PRE followed by repeat applications of clopyralid at 79 g ha^-1 with glufosinate or glyphosate provided burndown control of up to 5-cm weeds and provided greater than 95% season-long common ragweed control or greater common ragweed control than repeat glyphosate and clopyralid applications at 1.05 kg ha^-1 and 79 g ha^-1 with NIS and AMS in 2022. Repeat glyphosate applications with dicamba or glufosinate at the 4 to 6-lf or 8- to 10- lf sugarbeet stage, respectively, provided greater than 95% kochia control of up to 10-cm kochia as compared with kochia control from repeat glyphosate applications alone or repeat glyphosate and ethofumesate applications following ethofumesate PRE.

The current method for determining nitrogen (N) requirement in sugarbeet, the Yield-Based Approach, calculates N fertilizer requirement by applying a ‘lb N per ton beets’ multiplier to the projected yield for a given field. As yields continue to increase over time, this method results in higher and higher N recommendations and a constant demand for research-based updating of the N multiplier. Despite the trend for increasing yields, research has shown the amount of N required to achieve those yields has remained relatively stable. For this reason, researchers from Amalgamated Sugar’s SBQI team, in partnership with soil scientists at the USDA-ARS, have been exploring possible alternatives to the yield-based approach. From 2014 to 2018 a study of 14 fertility field trials concluded that nitrogen requirement could be reduced in the Pacific Northwest and that a flat-rate, or static, approach should be considered as an alternative to the yield-based approach (Tarkalson et. al, 2014). Further work in 2018-19 at 6 field sites identified a static-N range of 180–230 lb N/acre was optimal to maximize sugarbeet yield and quality. This report details the findings of static N research at a further 6 field sites in 2020 and 2021. These studies compared the Yield-Based approach to a range of Static N alternatives (180, 205, 230 lb N/A), as well as N recommendations from a commercial soil testing laboratory. Results showed the Static rate approach better matched N supply with crop need, and that both the Yield-Based Approach and Soil Lab recommendations significantly over-estimated N fertilizer requirement. The current Yield-Based method resulted in an average of 81 lb N/acre excess fertilizer N when compared to the Static N approach.

An accurate soil test provides the foundation for determining the optimal amount of fertilizer required for a sugarbeet crop. While some nutrients do not change much from fall to spring, others are more variable. It is well understood that available soil nitrogen (N) is dynamic and changes over time in response to natural processes such as mineralization, leaching, denitrification, immobilization, and human interventions such as tillage and residue management. For this reason, it is commonly recommended that soil sampling for N occur as close to planting as possible. Soils sampled too far ahead of planting are less able to accurately measure soil N available to sugarbeets at planting. This results in N fertilizer recommendations that may be sub-optimal for sugarbeet production and/or profitability. Despite these concerns, sugarbeet soils are routinely sampled in the fall, often as early as August. In the lead up to the 2020 crop year, Amalgamated Sugar sampled 1173 fields prior to January. This represented  43% of total contracted fields. With more than 2000 sugarbeet fields to sample each year, it would be logistically challenging to require that all fields be spring sampled. Instead, it is possible that improvements could be made to the fall soil sampling program if it was understand how much soil test N varies due to time of sampling. This report details the results of monthly soil sampling at 15 commercial sugarbeet fields in the fall of 2021 and spring of 2022. We found that soil samples taken in the fall significantly underestimated total available N relative to spring samples. As a result, fertility recommendations based on fall soil tests overestimated fertilizer N requirement resulting in unnecessary cost to the grower and the potential for negative impacts on sugar % and sugar quality. This work suggests that fertilizer recommendations based on fall soil tests could be improved by considering  their tendency to underestimate soil available N relative to spring soil tests.

Phosphorus (P) is second only to nitrogen in importance for optimizing growth, crop yields, and quality. Despite its importance deficiency in sugarbeets can be common, particularly during early spring when soils are cold and sugarbeet roots are small.  Diagnosis is not always easy as phosphorus deficiency is widely regarded as the most difficult nutrient disorder to diagnose in sugarbeets. It is not uncommon for P-deficiency to be misdiagnosed as nitrogen (N) deficiency, resulting in potential for over-supply of N and reduced beet quality. A wide range of symptoms are attributed to P-deficiency, many of which, such as purpling of leaves, are often listed in one diagnostic key only to be omitted altogether by another. This has led to disagreement amongst sugarbeet agronomist as to what visual symptoms best describe P-deficiency in sugarbeet grown on Idaho soils. In response to this, a glasshouse study was established in 2020 to document the visual symptoms of P-deficiency across 4 levels of soil P supply (3, 10, 15, and 27 ppm-P).  A follow up study, with the same treatment levels, was established in 2021 to investigate symptom expression across 10 commercial sugarbeet varieties.  These studies found that many commonly described P deficiency symptoms, such as delayed emergence, yellow cotyledons, purpling of leaves, brown veining of older leaves, crinkling of leaf margins, and leaf cupping, were not reliable indicators of P-deficiency. Rather, the most reliable and consistent indicators of P-deficiency were slow leaf production and reduced plant size, smaller and somewhat darker green first true leaves, and some degree of upright leaf habit in young leaves. All ten varieties showed remarkably similar symptom expression. This work has helped Amalgamated crop advisors better recognize the symptoms of sugarbeet P deficiency in Idaho soils.

Sugarbeet production on soils with a long history of manure or dairy compost additions can be challenging. Often containing more than 400 lb N/acre, these soils are much higher in nitrogen than is recommended for optimal sugarbeet productivity.  High nitrogen is known to reduce sugar % and increase impurities in sugar juice. This results in a higher sugar purity penalty which then reduces the beet payment to growers. In addition to manured fields, high nitrogen can also be a problem for sugarbeets following onion or potato rotations, which are often highly fertilized. Unable to reduce soil nitrogen, growers have few options available to them. Selecting a variety that performs well under these conditions therefore becomes critical. While there is some anecdotal evidence suggesting certain varieties do perform better than others under high nitrogen conditions, these claims have not been tested. This study reports the findings of Agridata analysis and field trial research investigating the performance of 30 commercial sugarbeet varieties under normal (250 lb N/A) and high (450 lb N/A) nitrogen growing conditions.  Although most varieties showed increased yield, overwhelmingly, high-N led to reduced sugar %, higher conductivity, and greater sugar juice impurities in the form of higher brei nitrates. Despite this, there were clearly some varieties that performed better than others and were able to overcome their reduced sugar % and purity penalties by delivering much higher yields. This work provides variety recommendations for growers with high nitrogen soils.

The goal of Southern Minnesota Beet Sugar Cooperative is to optimize the factory’s capacity. To do this the grower’s goal is to raise enough high-quality sugar beets to meet the needs of the factory. This may occasionally mean that some sugar beet acres will not be harvested because of greater than anticipated root yield and a limited factory slice capacity. Little information exists on management practices for optimum field corn production following unharvested sugar beet. The objectives of this study were to determine if the unharvested beet roots need to be removed, if starter fertilizer would increase corn grain production, and if corn needs more nitrogen applied after unharvested beet roots compared to harvested beet roots. This trial was conducted as a randomized complete block with four replications and repeated over four years. Plots contained either harvested or unharvested beet roots from the previous growing season with all the fertilizer being applied to the corn in the spring based upon a two-foot soil sample.

All four years had very different environmental conditions. There was an interaction between treatment and year for corn grain yield. However, this interaction was in the magnitude of grain yield response. In all years, corn grown in plots where beet roots were not harvested had less grain yield than corn grown in plots where the beet roots were harvested. In all production years, the use of an extra 40 lbs of nitrogen per acre over the standard recommendation increased the corn grain yield in the plots where the beet roots were not harvested. The results from all years shows the importance of additional nitrogen for field corn production after unharvested beet roots because of the tie-up of nitrogen from the extra carbon left in the soil by the unharvested beet roots.

Common ragweed (Ambrosia artimisiifolia) is a troublesome summer annual broadleaf weed in sugarbeet in Minnesota and North Dakota. Growers attending the 2022 sugarbeet growers’ seminars reported common ragweed as their second most troublesome weed following waterhemp (Amaranthus tuberculatus). Past experiments investigating chemical control options reported targeting common ragweed less than 5-cm with repeat glyphosate plus clopyralid applications at 1,010 g ha^-1 plus 53 g ha^-1, respectively, provided 92% control. Repeat applications of clopyralid plus glyphosate were more effective on both small (≤5 cm) and larger (≤10 cm) common ragweed; however, common ragweed 15-cm or greater were too large for POST control in sugarbeet. Recent greenhouse evaluation of common ragweed sourced from fields with weed control failures confirmed that the application of glyphosate alone is no longer an effective mode of action for common ragweed control. In addition, certain common ragweed populations from 2021 also demonstrated alarming tolerance to clopyralid; however, clopyralid eventually provided common ragweed suppression at 158 g ha^-1. A field experiment conducted in 2022 considered common ragweed control from a more concentrated formulation of clopyralid (Stinger HL) at different rates, timings, and tank mixtures. Results suggest common ragweed populations are adapting to sugarbeet herbicides and sizes ranging from 5- to 10-cm are becoming increasingly difficult to control. Clopyralid rates to 105 g ha^-1 plus glyphosate provided unacceptable control when applied to common ragweed greater than 5-cm. Targeting common ragweed less than 5-cm with repeat clopyralid applications at 79 g ha^-1 or greater plus glyphosate at 1,050 g ha^-1 provides the greatest common ragweed control in sugarbeet. Timing herbicide applications to common ragweed size rather than sugarbeet growth stage is crucial.

Growers in the Imperial Valley have adopted glyphosate resistant varieties in their sugar beet production system.  One of the advantages of the use of glyphosate resistant varieties is the reduction of the need to cultivate for weed control at layby (November).  This cultivation operation at layby was also combined with a split application of nitrogen.  The cultivation at layby required that irrigation basins be deconstructed for equipment access to the field and then rebuilt following the cultivation.  With the advent of glyphosate resistant varieties, weed control is obtained without cultivating and thus the irrigation basins do not need to be deconstructed.  This requires growers to apply their nitrogen fertilizer pre-plant instead of the former split application.  The objective of this study was to determine the effect of nitrogen rate and timing on sugar beet root yield and quality.  The study was established at four locations from 2017 to 2020.  The treatments were a factorial combination of eight nitrogen application rates (0, 40, 80, 120, 160, 200, 240, and 280 lbs. N per acre) and two application timings (pre-plant and layby).  This study suggests that delaying N application until November is not needed and that the optimum N application rate for sugar beets harvested in June and July was 220 lbs. N per acre with another 100 lbs. soil nitrate-N per acre in the surface 43 inches of soil at planting.

Adequately high potassium (K) nutrition is essential for high sugar yield and quality of beet crops.: We quantified the effect of potassium deficiency on sugar beet dry matter and sugar yield formation during the growing season. Sugar beets were grown on low, medium, and high soil K concentrations in a long-term K fertilizer field experiment on a silt loam alluvial soil. Plants were harvested at four time points during the growing season, including the final harvest. At each harvest, the dry matter yield and K concentration of leaves and beets (when applicable) were recorded. In autumn, sugar concentration and beet quality were measured.  Low soil K concentrations resulted in an approximately 10% lower sugar yield compared to high soil K supply. Reduced growth of low K plants already occurred during the germination phase and in the first weeks thereafter, whereas later growth rates were similar. Higher soil K levels increased K uptake rate and thus a higher final total K uptake. High K plants showed rapid early growth and maximum growth rates were achieved earlier than by low K plants. The initial differentiation between the low and high K treatments persisted due to similar growth rates in subsequent phases at both low and high soil K.  It is concluded that under overall low soil K conditions, adequate amounts of K fertilizer should be applied to meet the demand of sugar beet seedlings for maximum growth and final sugar yield. Banded K fertilizer application next to the plant rows is supposed to be efficient for this purpose.

Cover crops (cc) are supposed to decrease the soil mineral N content (Nmin) during winter and increase the N supply to subsequent main crops due to mineralisation of N previously prevented from leaching. However, data on N supply from cc grown before sugar beet and maize have rarely been reported for Central European conditions. Therefore, our study aimed to provide information for cc differing in frost resistance and biomass quantity.  In 2018/19 and 2019/20, field trials were conducted on three Luvisol sites in Germany, comprising a sequence of either fallow or autumn sown cc (oil radish, saia oat, spring vetch and winter rye) followed by sugar beet and maize main crops sown next spring. Immediately before sowing, cc plant material was incorporated by tillage to 10-25 cm soil depth. The N effect of cc on sugar beet and maize was calculated as the difference in plant N uptake after a specific cc compared to bare fallow for distinct phases of the growing season.  Winter rye and oil radish cc revealed the greatest potential for scavenging nitrate from the soil profile while reductions caused by frost-sensitive saia oat and spring vetch were more variable. The amount of N in the cc biomass was negatively correlated with soil Nmin in autumn. Thus, for environmentally effective cover cropping in Central Europe, species with a sufficiently high frost tolerance should be chosen.  Despite cc N uptake of up to 170 kg N ha^-1 and C:N ratios were < 20, for sugar beet a positive N effect was found between March and July only and amounted to 20 kg N ha^-1 at maximum, while between August and September, net immobilization was predominant with up to 40 kg N ha^-1. In contrast, for silage maize the N effect was close to zero from sowing until July but clearly positive with values up to 60 kg N ha^-1 in the second half of the growing season. Differences among cc species were not consistent across the site/years investigated. Sugar yield was lowest after rye and correlated positively with Nmin in spring. Maize total plant dry matter yield revealed no clear differences among cc. Correlation between yield and cc N effect was low and not improved by a multiple regression approach.  Thus, factors other than in-season N supply from cc apparently impacted yield to a larger extent. For sugar beet, we hypothesize that the rapid depletion of the upper 30 cm soil layer from nitrate by the crop might cause substantial N immobilization during cc biomass decomposition in the summer months. In contrast, under maize N uptake is delayed, fostering microbial breakdown of and N release from the cc biomass.

Sugarbeet is one of two crops supporting sugar demand in the U.S. In the Red River Valley of North Dakota and Minnesota, postharvest sugarbeet roots are stored for up to eight months prior to processing into sugar. During storage, endogenous metabolism and microbial activity cause root deterioration and sucrose loss. Furthermore, microorganisms, especially bacteria present in the processing streams at sugar factories cause additional sucrose loss and processing challenges due to biofilm formation and exopolysaccharide production. We recently examined postharvest sugarbeet roots to identify the major microbial isolates that are present and likely to cause disease and sucrose loss during storage. Bacteria present in factory diffusion tower raw juice were also identified. Knowledge of the microbial communities present in postharvest sugarbeet roots and factory processing streams aid in developing management strategies that limit sucrose loss during sugarbeet root storage and processing.

Sugarbeets were widely grown throughout California during the 20^th century, but the last sugar factory in the northern California closed in 2008.  In the absence of a sugar industry, interest in the use of sugarbeets as a silage feedstock for dairy cows has grown, especially in the San Joaquin Valley (SJV).  Increasing regulatory restrictions on the availability of water for irrigation and stricter controls on nutrient management support the use of alternative crops by dairy producers that are both water use efficient and capable of recovering both water and nutrients at depth in the soil profile.  Sugarbeets can be planted in fall in the SJV, and harvested in late spring/early summer.  When grown through the winter, water use is approximately half that of a summer crop (2 ac ft compared to 4 ac ft).  Beets have been documented recovering water and nutrients at 3 m in depth, deeper than alternative winter annual forages.  Most pests and pathogens common to summer crops are avoided during winter.  If winter beet production proves viable on dairies in the San Joaquin Valley, a large market for hybrid seed would develop, potentially dwarfing previous uses for sugar alone in the region.  Four trials on dairy farms growing and feeding sugarbeets for silage have been carried out during the 2018 to 2022 period.  Beets were planted using strip tillage methods following corn silage in fall (late October and early November) in heavily manured fields and harvested in early to late June.  Root yields varied from approximately 60 t/ac to 43 t/ac depending largely on stand establishment and uniformity.  Tops were not harvested due to concerns about nitrate content and technical limitations around harvesting and feeding.  No pest or disease issues were observed except for flea beetle predation on seedlings in year three at one site.  A formal feeding trial was carried out in year there and beet-almond hull silage replaced corn silage and some corn grain in rations fed to high producing cows with no change in yield or milk quality.  Cows consumed rations avidly and body conditions scores were equivalent throughout the trial.  In years one and two, beets were co-ensiled with almond hulls and both years, in years three and four, beets were co-ensiled or ensiled with additives.  Significant barrier to the wider-scale adoption of beets on diaries in the SJV remain.  These focus on difficulty of preserving dry matter energy in beets during storage.  In two years of measurements, shrinkage (loss) of preserved dry matter was continuous throughout the storage period and averaged 35 %, compared to 5% or less for corn silage. Other barriers to adoption are the need for beet harvesters, some adjustments in forge wagons, the need for ag bags compared to bunker silos for preservation, and slower harvests and handling.  These problems have not been solved adequately to date, especially those concerned with storage DM losses.

This research focusses on identifying less toxic substitutes for chlorpyrifos (Lorsban®) in sugarbeet production in the Imperial Valley.  Chlorpyrifos is a known neurotoxin and affects both humans and other animal and fish species.  It is hazardous to applicators and workers, has been shown to accumulate in the Salton Sea and has been restricted in California. The primary insects affecting stand establishment are diverse flea beetle species, primarily pale stripped flea beetle (Systena blanda) and armyworm species (Spodoptera sp.).  In spring with rising temperatures, army worms and diverse leaf hoppers (Empoasca sp.) can reach pest level.  Low risk strategies for stand establishment emphasize IPM practices including pre-irrigation of fields, dates of planting, and seed treatments.  Complementary field experiments were carried out over the 2020 to 2022 period at UC Desert Research and Extension Center (DREC), integrated with complementary trials in 6 growers’ fields.  Poncho Beta® (clothianidan + cyfluthrin-PB) seed treatments are a reduced toxicity standard common to all station and field experiments.  Data collected include seedling emergence and loss, seedling dry weight at establishment, season-long estimates of insect pest abundance and damage, yield and root quality, and comparative costs of differing treatments.  At the UC DREC, pesticide treatments were compared to untreated controls within pre-irrigated or dry-planted treatments, at two different planting dates (mid-September and mid-October).  Additional soil treatments at planting are compared and include granular, soil-applied chlorpyrifos, Coragen® (chlorantaniliprole), PB seed treatments and PB plus Coragen®.  These plots are split and half include additional post emergence control with Asana® (esfenvalerate), commonly used in growers’ fields.  A randomized block design is used in growers’ fields with different treatment comparisons depending on the grower and year.  Typically, three treatment comparisons were carried out using chlothianidan alone or in combination of without clothianidan.  Strips (plots) 50 to 60 feet wide the length of the field were compared.  The common practice used by each grower was the control in each field.  Yields and pesticide use and costs were tracked for all trials and compared.  The Pesticide Risk Tool (https://pesticiderisk.org/about) was used to compare treatments and risk.  In general, seed treatment with clothianidin, a neonicotinid, was as effective as other pesticide combinations, tended to be less expensive, and rated lower on the pesticide risk scale compared to most other pesticide-use strategies or superior to other pesticides used in the trials.  Results from the trials are reported and discussed.

Sugarbeet roots are subject to tremendous physiological stress at harvest as defoliation and extraction from the soil removes roots from their source of photosynthate, water, and nutrients, and harvest and piling operations inflict injuries to roots. Roots additionally encounter environmental stress during storage from declining and fluctuating temperature and humidity conditions within piles. The physiological and environmental stresses of harvest and storage are certain to affect sugarbeet root postharvest metabolism as well as impact sugarbeet root storage properties, processing properties and sucrose yield after storage. However, the molecular changes occurring in postharvest sugarbeet roots and their relationship to root storage and processing properties are largely unknown. To better understand the molecular events occurring after harvest and their relationship to storage and processing losses, genes and metabolites that were altered in expression or concentration in roots stored at 5 and 12°C for 12, 40 and 120 days were determined and correlated to changes in root storage and processing properties. RNA sequencing and HPLC-MS analysis identified 8656 genes and 225 metabolites that were altered in expression or concentration at one or more time points during the 120 day storage period, at one or both storage temperatures. Functional annotation and pathway analysis indicated that differentially expressed genes and metabolites contributed to a diverse array of regulatory, structural and metabolic pathways, while correlation analysis identified genes and metabolites that exhibited positive or negative relationships in their expression or concentration with the deterioration in root storage and processing properties. Overall, the research indicates that a major reorientation of metabolism occurs after harvest and throughout storage and identifies genes and metabolic pathways that potentially contribute to storage losses.

As the sugar content of sugar beet crops increase, profitability increases. An obstacle to raising a high sugar content sugar beet crop in the southern Minnesota growing region is high levels of total available soil nitrogen. Sugar beet yield increases with soil nitrogen, but sugar beet quality is detrimentally impacted by soil nitrogen. The objective of this study was to determine if a producer can increase harvest plant population in high nitrogen situations and mitigate the negative impacts of the excess nitrogen. This study was conducted in two environments during the 2019, two environments in 2020, and one environment in 2021 in a replicated complete block design with a split plot arrangement of six replications.  Four nitrogen rates comprised the whole plot and two plant populations comprised the split plot arrangement and were applied at both locations. Fertilizer was applied by hand to reach a total available soil nitrogen level of 120, 160, 200, and 240 lbs ac^-1 and incorporated with a field cultivator.  Sugar beets were planted at a rate of 120,000 plants ac^-1 to ensure adequate establishment, and stands were thinned to populations of 43,800 and 71,300 plants ac^-1 28-38 days after planting.   The highest sugar content sugar beet crops were produced on soil fertilized to 120 lbs total available soil N ac^-1.  Plant populations did not significantly impact sugar beet quality. Extractable sugar per acre was highest at 240 lbs available soil N ac^-1 and 71,300 plants ac^-1. Extractable sugar per ton was highest at 120 lbs available soil N ac^-1.

Intellectual property (IP) protection in the US recognizes the value of innovation and enables purposeful access to such innovations across the sugar beet industry.  US Patents and Plant Variety Protection (PVP) are two forms of IP protection that are available to continue providing breakthrough technological developments directed to supporting the continued growth and success of our industry.  Research and development are essential for the continued advancement of the sugar beet industry. Research institutions, government agencies, corporations and others in the industry have made, and continue to make, significant and long-term investments in R&D to provide new innovations in sugar beet research, increasing the yield potential as well as the stability of the crop to tolerate stresses caused by disease, weeds, and insect pressure.  The US IP systems serve to support these investments by rewarding innovation and incentivizing future investments in R&D.  The advantages of the US IP systems are utilized throughout the sugar beet industry, ranging from innovations in crop genetics, to process technology optimization and product refinement.  The United States Patent and Trademark Office (USPTO) examines patent applications under the US Patent laws directed to the utility, novelty, and non-obviousness of an innovation, in view of the caselaw interpreting those laws. In doing so, the US patent system appropriately grants a limited protection only to those innovations that meet these rigorous standards. The USPTO has further streamlined its examination process to eliminate laws of nature or natural phenomena from patent-eligible subject matter, so only useful, new, and non-obvious innovations are eligible for patent protection in the US for a statutorily defined period of time.  Plant Variety Protection is another form of IP and is administered through the USDA’s Plant Variety Protection Office.  PVP registration protects new, distinct, uniform, and stable (DUS) plant varieties and enables the management of the use of these varieties by other breeders.  A PVP owner has the ability to allow the use of a protected variety for breeding by others to develop new varieties, thereby providing a platform for continued innovation and incentivizing the development of new and improved varieties.  The sugar beet industry must meaningfully address the challenges which lie ahead of us, like climate change, sustainability, and feeding the growing world population, using all the benefits of the IP systems to continue to foster innovation through R&D.

Establishing an adequate sugar beet population is one of the first challenges of sugar beet production. Sugar beet is planted in the Imperial Valley of California during September and early October. Daily high temperatures often exceed 100 degrees F in the first half of September. In addition, soils in the Imperial Valley often have significant salt content. This combination creates a harsh environment for sugar beet emergence. Fields are furrow irrigated in the Imperial Valley; however, installing sprinkler irrigation during the sugar beet emergence period is being considered by growers to increase sugar beet emergence in their fields.  After the emergence period, the sprinkler pipe is removed, and the fields are furrow irrigated for the remainder of the season. Two projects were developed to quantify potential emergence and yield differences between sprinkler and furrow irrigation during the sugar beet emergence period. A field survey of sprinkler and furrow irrigated production fields planted during September was conducted by the Spreckels Sugar Agricultural Staff during the 2020-2021 and 2021-2022 growing seasons. The field survey showed a 6.3% increase in emergence with sprinkler irrigation in 2020-2021 and an 8.0% increase with sprinkler irrigation in 2021-2022 compared to furrow irrigation. Sprinkler irrigation during emergence averaged 1,119 lbs. of extractable sugar per acre greater than furrow irrigation in 2020-2021 during the first seven weeks of harvest and 312 lbs. of extractable sugar per acre greater than furrow irrigation in 2021-2022 during the first five weeks of harvest.  A replicated trial was conducted at the Imperial Valley Research Center during the 2021-2022 season, looking at sprinkler versus furrow irrigation for emergence and yield. The trial was conducted as a randomized complete block with a split plot arrangement. In this trial, the sprinkler irrigated treatment emergence was 23.6% greater than the furrow irrigated treatment at the initial emergence count. The sprinkler irrigated treatment yielded 312 lbs. of extractable sugar per acre greater than the furrow irrigated treatment. The field survey and the trial at the Imperial Valley Research Center will be repeated for the 2022-2023 growing season.

Sugar factories worldwide are facing several challenges, and the need to reduce costs of production and improve process efficiency is paramount. A repeatable analytical process is key to ensures consistent, high-quality data. The KWS BEETROMETER^®, based on a process NIRS system, is an innovative system for standardized and full automated quality analysis of sugarbeets. The automated system reduces lab cost, lead to improvement in efficiency and low costs for maintenance and can be easily implemented in existing receiving labs.  The previous measurement method involved processing sugarbeets into brei during sample preparation and then analyzing the brei for sugar content and non-sugar substances. The KWS BEETROMETER^®, fully automated process, involves crumbling the beets into pieces and on a conveyor belt, a near-infrared spectrometer (NIRS) determines the sugar content as well as other quality-determining factors.  As companies look to implement KWS BEETROMETER^® in the receiving lab processes a big challenge is to design comparison test, based on high heterogeneity in distribution of quality compounds within and across beets. The production of a representative and reliable brei sample is influenced by the whole sample preparation process.  Understanding the effects of the brei production and processing differences can aid in suitable process comparisons.  Experience during implementation of the KWS BEETROMETER^® at customers will be shown. During the accompanied transition from the previous measurement process to the new one many different analyses are performed. This includes not only the instrumental comparison but every process step in the quality analysis of sugar beets in the receiving labs. As an example of this, experimental results of brei processing and the influence on the reliability of quality parameter results will also be presented.

Rinskor active (flopyrauxifen- benzyl) belongs to the arylpicolinate class of chemistry, a new structural class of the synthetic auxin (Group 4) herbicides.  Rinskor is currently registered as Loyant® herbicide in the US for use in rice where it has broad spectrum activity on grasses, broadleaves, and sedges.  Rinskor has a low use rate (<30 g ai/ha), a favorable environmental and toxicology profile, rapid degradation in the soil and plant tissue, and little persistence in the environment.  Due to its favorable profile, Rinskor received a “reduced-risk” review from EPA and a residue tolerance exemption in October 2019.  Corteva is exploring potential opportunities to expand Rinskor into other crops including sugar beet.  In Europe, Rinskor has been evaluated on sugar beet as part of a POST program where 3-4 POST applications are made in sugar beet.  Results indicate that sugar beet has acceptable tolerance to Rinskor when applied from cotyledon to 6 leaves and that Rinskor provides good control of weeds in the Chenopodiacea, Apiaceae or Umbellifera families.  In the United States, sugar beet growers can use glyphosate, a valuable tool in managing weeds on glyphosate-tolerant sugar beet.  However, glyphosate resistance has continued to spread and additional weed control options in sugar beet are limited.  Previous work has indicated that Rinskor provides excellent control of difficult-to-control weeds such as common lambsquarters (Chenopodium album) and other broadleaf weed species.  In 2021, two trials were conducted in ND/MN utilizing Rinskor in sugar beet to evaluate crop tolerance and control of glyphosate-resistant waterhemp (Amaranthus tuberculatus).  Initial results from this work indicated that 0.5-1.0 g ai/ha of Rinskor applied prior to 10-leaf sugar beet as the potential target rate range and application timing.  In 2022, several trials were conducted throughout the sugar beet growing regions of the US.  Rinskor applied alone caused visible crop response to sugar beet and the addition of glyphosate, ethofumesate, and s-metolachlor increased crop response.  Two applications of a program treatment including Rinskor provided good to excellent control of common lambsquarters, waterhemp, Palmer amaranth (Amaranthus palmeri), kochia (Kochia scoparia), and common ragweed (Ambrosia artemiisifolia).  Future work in the United States will continue to define the use rate and program treatments required to manage weeds with Rinskor in sugar beet.

A sugar beet growth rate study was conducted in Alberta using a high root yield variety and a high sugar content variety. The objective of this study was to measure sugar beet root yield increases and sugar accumulation in both sugar beet varieties. Tests were conducted at 4 different locations between 2018 and 2021. Varieties were harvested approximately bi-weekly starting on July 15 and were measured for six consecutive treatment dates during the growing season ending in early October. Sugar loss to molasses was not measured due to instrumentation limitations for early harvest dates; therefore, sugar was referred to as gross sugar and not extractable sugar. For gross sugar per tonne and percent sugar, site years were analyzed separately due to an interaction that occurred between fixed and random factors. Root yield growth averaged approximately 340kgs/acre per day or 2.4 tonnes/acre per week for the high root yield variety and 310kgs/acre per day or 2.15 tonnes/acre per week for the high sugar content variety over the entire harvest period. Gross sugar per acre (GSA) increased 70kgs/acre per day or 492kgs/acre per week for the high root yield variety and 66kgs/acre per day or 460kgs/acre per week for the high sugar content variety. Gross sugar per tonne (GST) increased 1.0kgs/tonne per day or 6.9kgs/tonne per week for the high root yield variety and 1.2kgs/tonne per day or 8.1kgs/tonne per week for the high sugar content variety. Gross sugar per tonne was significantly (P<0.05) higher for the high root yield variety on the first harvest date, which was unexpected. On the second harvest date, the high sugar content variety had numerically higher GST. For the remaining 4 harvest dates, the high sugar content variety produced significantly (P<0.05) higher GST. This result provided strong evidence that the higher quality variety started slower but eventually surpassed the high root yield variety in quality. Maximum root yield and gross sugar per acre production occurred for both varieties between August 1 and August 14. Gross sugar per tonne and percent sugar accumulated the fastest between July 15 and July 31 for both varieties and slowed considerably between the second-last and last harvest dates. It was concluded that varieties vary in their sugar accumulation profiles over time and across multiple years.

Glyphosate-resistant (GR) waterhemp (Amaranthus tuberculatus) and common ragweed (Ambrosia artemisiifolia) are weed control challenges in sugarbeet in North Dakota and Minnesota. Sugarbeet growers control GR weeds using soil residual chloroacetamide herbicides (group 15) for waterhemp control and clopyralid (group 4) for common ragweed control. However, growers need additional effective herbicides to improve the consistency of broadleaf weed control in sugarbeet. Florpyrauxifen-benzyl (Rinskor) is a mimic auxin herbicide (group 4) which controls susceptible plants by disrupting plant growth processes. Rinskor is labeled as Loyant for postemergence grass, sedge, and broadleaf weed control in rice at 30 g ha^-1 in Arkansas, California, Florida, Louisiana, Mississippi, Missouri, South Carolina, Tennessee, and Texas. Experiments conducted in Europe suggest sugarbeet may tolerate Rinskor to 2 g ha^-1. Experiments to examine crop safety and selective weed control from Rinskor were conducted at six locations in Minnesota and eastern North Dakota in 2021 and 2022. In 2021, Rinskor at 0.5, 1, 2, and 4 g ha^-1 was applied at the 2, 6, or 10 sugarbeet leaf stage and in 2022, repeat applications of Rinskor at 0.5, 1 and 2 g ha^-1 alone or in mixtures with glyphosate, ethofumesate and S-metolachlor were applied at the 2-lf and 6-lf stage. Waterhemp control in 2021 and 2022 and common ragweed control in 2022 were compared to standard sugarbeet weed control programs. In 2021, sugarbeet tolerated Rinskor at 0.5 and 1 g ha^-1 at the 2- and 6-lf stage, but sugarbeet did not tolerate the 10-lf stage of application. In 2022, sugarbeet tolerated repeat Rinskor applications at 0.5 and 1 g ha^-1 at the 2- and 6-lf stage. Sugarbeet root yield from Rinskor at 0.5 and 1 g ha^-1 at the 2-lf and 6-lf stage was the same as the untreated control in 2021, but Rinskor at 1 g ha^-1 repeated at the 2- and 6-lf stage reduced root yield in 2022. Rinskor did not affect % sucrose content in either 2021 or 2022. Rinskor alone at 0.5 or 1 g ha^-1 only provides suppression of waterhemp or common ragweed, and will therefore need to be mixed with other sugarbeet herbicides including the chloroacetamides to achieve 95% or greater waterhemp control and clopyralid to achieve 95% or greater common ragweed control.