Simplified cereal-based crop rotations are widely grown due to economic reasons, leading to the cultivation of wheat after wheat and associated yield losses. In this study, a crop rotation trial was conducted in Northern Germany on a Stagnic Luvisol from 2006 to 2018 with winter wheat after the four most widely used preceding crops in the region (sugar beet, winter wheat, silage maize and winter oilseed rape) in different crop rotations to evaluate potential benefits of different preceding crops. Additionally, the effects of two different sowing dates (2016–2018) and higher crop residue input (whole period) were investigated.

While the pre-preceding crop had no effect, preceding crops winter oilseed rape and sugar beet led to a significantly higher yield of about 1.00 and 0.43 t/ha, respectively, compared to wheat after wheat. This was not modified by crop rotational diversity, including wheat monoculture. Wheat yield tended to be higher for the late sowing date after sugar beet, maize and wheat, while there was no effect of sowing date after oilseed rape. Higher crop residue input led to a significantly higher yield (0.30 t/ha) in wheat after wheat (after pre-preceding crop sugar beet). Overall, sugar beet and winter oilseed rape were found to be favourable preceding crops for winter wheat under the given site conditions. The effect of sowing date on yield and potential modifications of the preceding crop effect by sowing date needs further research in appropriate long-term trials.

Several studies have shown the negative effects of mature plant resistance (MPR) on aphids in sugar beet, which is correlated to the formation of black deposits in their stomach. However, the underlying mechanism of MPR still needs to be elucidated, by understanding the toxicity effects of MPR on aphids and the role of the plant phenological stage and the environment. Here, we report that MPR in sugar beet does not only affect Myzus persicae mortality rate and the formation of a black deposit in the aphid stomach, but also aphid fecundity and behaviour. In addition, experiments in climate-controlled and field settings showed quantitative variation in MPR to M. persicae between six genotypes of sugar beet. Our results indicate that environmental effects, such as temperature, play a major role in MPR and underscore the importance of proper climate-controlled experiments for investigating MPR. In climate-controlled experiments, 83.3% of aphids on old leaves developed a black deposit, in contrast to only 16.8% of aphids on young leaves. This shows that not only plant age, but also leaf age plays a major role in the intensity of MPR. Further research will be needed to identify the underlying mechanism, before MPR can be used as a viable and sustainable solution to aphid pests in sugar beet.

The objective of this WSSA Weed Loss Committee report is to provide quantitative data on the potential yield loss in sugar beet due to weed interference from the major sugar beet growing areas of the United States and Canada. Researchers and extension specialists who conducted research on weed control in sugar beet in the United States and Canada provided quantitative data on sugar beet yield loss due to weed interference in their regions. Specifically, data were requested from weed control studies in sugar beet from up to 10 individual studies per calendar year over a 15-yr period between 2002 and 2017. Data collected indicated that if weeds are left uncontrolled under optimal agronomic practices, growers in Idaho, Michigan, Minnesota, Montana, Nebraska, North Dakota, Ontario, Oregon, and Wyoming would potentially lose an average of 79%, 61%, 66%, 68%, 63%, 75%, 83%, 78%, and 77% of the sugar beet yield. The corresponding monetary loss would be approximately US$234, US$122, US$369, US$43, US$40, US$211, US$12, US$14, and US$32 million, respectively. The average yield loss due to weed interference for the primary sugar beet growing areas of North America was estimated to be 70%. Thus, if weeds are not controlled, growers in the United States would lose approximately 22.4 million tonnes of sugar beet yield valued at approximately US$1.25 billion, and growers in Canada would lose approximately 0.5 million tonnes of sugar beet yield valued at approximately US$25 million. The high return on investment in weed management highlights the importance of continued weed science research for sustaining high crop yield and profitability of sugar beet production in North America.

Seed–soil contact plays an essential role in the process of germination as seeds absorb water through direct contact with the moist soil aggregates that surround them. Factors influencing seed–soil contact can be considered as those pertaining to soil physical properties (e.g. texture, bulk density, porosity, etc.) and those related to environmental conditions (e.g. temperature, rainfall, frost). Seed–soil contact is furthermore influenced by the specific field management processes that farmers apply, which have developed significantly over the last 30 years. However, the precise effect of cultivation on the actual contact area of the seed with the surrounding soil is based on a series of assumptions and is still largely unknown. This review considers the influence of soil management and its direct impact on seed–soil contact and establishment. We review the state of the art in methodology for measuring seed–soil contact and assess the potential for soil amendments such as plant residues and waste materials to improve seed–soil contact. Engineering the ‘optimal’ seed–soil contact remains a challenge due to the localized variation between the interaction with field management techniques and soil texture, climatic conditions and crop type. The latest imaging approaches show great promise to assess the impact of management on germination. Combining the techniques with the latest network models offers great potential to improve our ability to accurately predict germination, emergence and establishment.

Whole-plant bioassays using sugar beet, lettuce, cucumber, green bean, pea, and soybean as test crops were used to detect mesotrione residues in the soil. The test crops were planted in soil treated with mesotrione in the field the previous year at rates of 0 to 560 g ai ha−1 and in nontreated soil from the same field, with mesotrione added at concentrations of 0 to 320 μg kg−1. Experiments were conducted in the greenhouse for a 21-d period. Values for the dose giving a 50% response (I50) were predicted using a log-logistic nonlinear regression model. I50 values (mean ± SE) of 8.6 ± 1.8, 14.9 ± 2.0, 29.8 ± 11.0, 41.6 ± 7.3, 52.9 ± 6.4, and 67.9 ± 30.3 g ai ha−1 for sugar beet, lettuce, green bean, cucumber, pea, and soybean, respectively, indicate that these crops were effective bioassay test species for quantifying mesotrione residues. A greenhouse bioassay was a simple and sensitive tool to detect mesotrione at concentrations of less than 1.0 μg kg−1 with sugar beet and lettuce being the most sensitive test species. The I50 values for soil treated with known concentrations of mesotrione were lower than for field soil treated with mesotrione the previous year. Knowing the level of mesotrione residues in the soil, growers have flexibility in crop rotations following mesotrione use on corn. Growers can use this information to minimize risk of crop injury by choosing appropriate rotation crops that suffer little or no yield reduction.

The interaction between ethylene production and seed germination of sugar beet (Beta vulgaris L.) was studied. For intact fruits, deoperculated fruits and true seeds, ethylene was only produced after the start of radicle emergence. Removal of the operculum or the whole pericarp, likely allowing better water uptake and gas exchange by the true seed, actually increased the time span between the start of radicle emergence and the beginning of ethylene production compared to intact fruits. ACC (1-aminocyclopropane-1-carboxylic acid), AOA (aminooxyacetic acid), AIB (2-amino isobutyric acid) and STS (silver thiosulphate) in the imbibition medium did not influence the germination pattern. Based on these findings, the function of ethylene during the germination of sugar beet is uncertain.

The seed reserves of sugar beet (Beta vulgaris L.) are starch, located exclusively in the perisperm, and lipids, proteins and a small quantity of soluble sugars, located mainly in the cotyledons. It is shown that lipids are the main respiratory substrate used during germination whereas starch and remaining lipids are only hydrolysed after root extrusion, to sustain root and hypocotyl growth. By removing the perisperm during imbibition, it was demonstrated that lipids and proteins alone are sufficient for viable seedling development, though such seedlings grew less than those developing in the presence of perisperm. The utilization of seed reserves was followed during seedling development in the dark in various organs. At 20°C, the reserves were sufficient for 8 d of growth in the dark, the hypocotyl attaining a length of 5 cm. Specific problems relating to field establishment of sugar beet are discussed in relation to these results.

Concerns have been raised in Europe about the efficiency, sustainability, and environmental impact of the first genetically modified crops. The committees and regulators in charge of approving procedures have encouraged a field trial approach for safety assessment studies under current agronomic conditions. We describe the gene flow from sugar beet (Beta vulgaris L.) in a multi-year and multi-crop monitoring study on farmers' fields at two locations that has been carried out since 1995. We analyzed two sugar beet lines that have been genetically transformed for herbicide resistance. One sugar beet has resistance to glufosinate and the other to glyphosate. Large differences among lines, years and locations were observed. These differences provided a broad range of situations to estimate the risks. Sugar beet bolters produced the majority (86%) of the herbicide-resistant seeds harvested in the field. Direct pollen flow from sugar beet bolters to weed beets that were growing within the same field as well as in a neighboring field that was left fallow accounted for only 0.4% of the resistant seeds released over the years and locations. Descendants of the hybrids between the sugar beet and the weed beet produced the remaining 13.6% of resistant seeds. Herbicide-resistant seeds from the progeny of the weed beet were recorded up to 112 m away from the closest transgenic pollen donor. Indications were observed of non-randomness of the weed beet producing resistant progeny. We also analyzed pollen flow to male-sterile bait plants located within and outside of the sugar beet field. Herbicide-resistant pollen flow was recorded up to 277 m, and fitted with an inverse power regression. Using sugar beet varieties with no, or very low, sensitivity to bolting and destroying bolters are two necessary measures that could delay gene flow.

Gene flow via seed or pollen is a basic biological process in plant evolution. The ecological and genetic consequences of gene flow depend on the amount and direction of gene flow as well as on the fitness of hybrids. The assessment of potential risks of transgenic plants should take into account the fact that conventional crops can often cross with wild plants. The precautionary approach in risk management of genetically modified plants (GMPs) may make it necessary to monitor significant wild and weed populations that might be affected by transgene escape. Gene flow is hard to control in wind-pollinated plants like beet (Beta vulgaris). In addition, wild beet populations potentially can undergo evolutionary changes which might expand their geographical distribution. Unintended products of cultivated beets pollinated by wild beets are weed beets that bolt and flower during their first year of planting. Weed beets cause yield losses and can delay harvest. Wild beets are important plant genetic resources and the preservation of wild beet diversity in Europe has been considered in biosafety research. We present here the methodology and research approaches that can be used for monitoring the geographical distribution and diversity of Beta populations. It has recently been shown that a century of gene flow from Beta vulgaris ssp. vulgaris has not altered the genetic diversity of wild Beta vulgaris L. ssp. maritima (L.) Arcang. in the Italian sugar beet seed production area. Future research should focus on the potential evolution of transgenic wild beet populations in comparison to these baseline data. Two monitoring models are presented describing how endpoints can be measured: (1) “Pre-post” crop commercialization against today's baseline and (2) “Parallel” to crop commercialization against GMP free reference areas/populations. Model 2 has the advantage of taking ongoing changes in genetic diversity and population dynamics into account. Model 1 is more applicable if gene flow is so strong that most areas/populations contain GMPs. Important traits that may change the ecology of populations are genes that confer tolerance to biotic and abiotic stress. An assessment of environmental effects can realistically only be based on endpoints and consequences of gene introgression, which may include economic values of biodiversity in littoral and other ecosystems containing wild beet. In general, there is still a great need to harmonize worldwide monitoring systems by the development of appropriate methods to evaluate the environmental impact of introgressed transgenes.

Broiler chickens were fed on a control diet based on maize or a diet containing sugar-beet-pulp fibre (Beeffiber) at an inclusion level of 46 g/kg. Diets were provided ad lib. or at a restricted level either once daily or three times daily. On days 13 and 20, chickens fed on the ad lib. control and sugar-beet-pulp-containing diets generally weighed more and had poorer feed conversion ratios than chickens given the restricted control and sugar-beet-pulp-containing diets respectively. Furthermore, chickens given the restricted diets once daily had greater body weights and generally improved feed conversion efficiencies compared with chickens given the restricted diets three times daily. Generally, elevated plasma Lipid concentrations were observed amongst chickens given the restricted diets once daily compared with chickens fed ad lib. as well as the restricted diets three times daily, while chickens fed on restricted diets three times daily had plasma lipid concentrations intermediate between those fed ad lib. and once daily. In a plasma triacylglycerol response study on day 22, feeding of sugar-beet-pulp-containing diets generally reduced postprandial triacylglycerol concentrations and delayed triacylglycerol response relative to chickens given the control diets either ad lib. or restricted, which may indicate gastrointestinal adaptation to feeding of a fibre-rich diet. Postprandial triacylglycerol concentrations observed for chickens receiving restricted diets were increased compared with chickens given the respective ad lib. diets, indicating adaptation of chickens to reduced feed frequency. On day 25, feeding of sugar-beet-pulp-containing diets decreased digesta dry matter content and ileal organic matter digestibility. Chickens given sugar-beet-pulp-containing diets generally had, on day 25, increased caecal short-chain fatty acid (SCFA) concentrations in comparison with chickens given the ad lib. control diet, indicating increased fermentation of dietary components. It is also noteworthy that the greatest SCFA concentrations were observed amongst chickens given the control diet once daily, suggesting enhanced caecal fermentation capacity. This may have been a consequence of increased bacterial activity and caecal hypertrophy due to infrequent feeding of a low-fibre diet.