Autumn-sown Sugar Beet Research Articles

An Alternative to the Water Scarcity in Conventional Summer Sugar Beet (Beta vulgaris L.) Cultivation: Autumn-Sown and Non-irrigated Under the Aegean Coastal Zone Conditions

AbstractSummer sugar beet growing regions such as the Central Anatolia Region of Türkiye face a shortage of irrigation water. For this reason, we tested autumn sowing sugar beets without irrigation in the Aegean Coastal Zone, where sugar beet cultivation is not practiced. The two-year study was conducted in a split-plot experimental design with four replications. Terranova, Aranka and Dionetta cultivars were sown on 1 December 2020 and 30 November 2021. Ridge sowing was implemented to minimize the possibility of bolting and to prevent them from being affected by excessive December, January and February rainfall. There was no frost-induced seedling loss during the winter growing season and no bolting in the following spring in both years. Growing degree days (GDD) from emerging to harvest (1956 vs. 1497) were higher in the yielding year. Higher solar radiation in the first year (757.30 kWh m−2 vs. 673.80 kWh m−2) during the vegetation period was positively associated with GDD and yield. Ridge sowing and Terranova cultivar performed superbly in terms of root yield, sugar content, SPAD value and Fv/Fm. It was concluded that autumn-sown sugar beet can be grown in the Aegean Coastal Zone as an alternative to the Central Anatolia Region without irrigation with the ridge sowing method.

Nitrogen reduction and foliar application of zinc sulfate improve the physiological and biochemical characteristics of two autumn-sown sugar beet (Beta vulgaris L.)

Nitrogen reduction and foliar application of zinc sulfate improve the physiological and biochemical characteristics of two autumn-sown sugar beet (Beta vulgaris L.)

Effects of sowing date on bolting and frost damage to autumn-sown sugar beet (Beta vulgaris L.) in temperate regions

Sugar beet is mostly cultivated in relatively cool regions of the temperate zones by sowing in spring, but in some Mediterranean areas with mild winters, the crop is sown in autumn. Due to global warming, autumn cultivation of sugar beet is gradually extending towards new areas that are still characterized by relatively cold winters. Seedling loss and bolting are two factors limiting the adoption of autumn sugar beet cultivation in new areas. The objectives of this study were to determine the effects of sowing date on (i) duration and rate of field emergence, (ii) phenological stages of sugar beet during early growth, (iii) quantitative traits of seedlings and (iv) bolting occurrence as well as frost killing of autumn-sown sugar beet. Field experiments were conducted in a randomized complete block design to determine the appropriate sowing date for autumn-sown sugar beet in 2017/18 and 2018/19 in the Karaj and Mashhad regions of Iran, which are both characterized by relatively cold winters. The experiment was conducted with a bolting-resistant cultivar and six sowing date treatments. The results showed that to reach plant growth stages of cotyledon, 2, 4, 6, 8, 10, 12, 14 and 16 leaves, 163, 200, 321, 418, 500, 600, 639, 700 and 757 growing degree days (GDD), respectively, were required. The average duration and speed of seedling emergence increased and decreased, respectively, with delay in sowing. The results suggest adjusting the sowing date of winter sugar beet so that when temperatures effective for bolting (6-8 °C) occur, the plant has already received about 300 to 400 GDD. At this time, the growth stage and the largest root diameter of sugar beet are approximately 4-6 leaves and 0.11-0.27 cm, respectively. After 14- to 16-leaf stage (≥700-750 GDD), the percentage of killed plants due to low temperatures were negligible. Although, the risk for frost losses is higher at 4- to 6-leaf stage (300-400 GDD), accepting higher losses is justified by a lower probability of bolting.

Evaluating the potential of winter beet in northern Germany by a simulation model

Abstract Autumn-sown sugar beets may achieve a faster canopy closure in spring compared to spring-sown sugar beets, thus increasing radiation interception and yield. However, to date yield benefits of autumn-sown beets cannot be quantified, as they start to bolt in spring. Therefore, simulation models for winter beet need to be developed. From 2009 to 2012, field trials in northern Germany were carried out with sugar beets sown in spring (conventional sugar beet) as well as sown in autumn (bolting winter beet). Based on these data, a dynamic simulation model was developed and calibrated for winter beets. The model is based on light use efficiency (LUE) approach and considered winter beet-specific aspects like leaf (area) losses due to frost, vernalisation and bolting. For conventional sugar beets, the validation revealed a RMSE of 164 g m-2 and a model efficiency (EF) of 0.93 for root dry matter. For the total dry matter (DMtot) of bolting winter beets, the validation showed a RMSE of 216 g m-2 and an EF of 0.69. Implemented assumptions regarding the non-bolting winter beets allow the model to simulate this beet type as well. A simulation over 12 years (1998-2010) for the site Hohenschulen estimated 1921 g DMtot m-2, 971 g DMtot m-2 and 2474 g DMtot m-2 for conventional sugar beets, bolting winter beets and non-bolting winter beets, respectively. Our results suggest that developing non-bolting winter beets seems be a promising approach to increase beet yields.

Effect of Extending the Growing Period on Yield Formation of Sugar Beet

AbstractAutumn sown sugar beets (winter beets) are expected to yield markedly higher than spring sown beets. This requires a continuous growth during an extended growing period. So far, bolting‐resistant sugar beet varieties are not available to test winter beets under field conditions in Central Europe. The objective of this study was therefore to analyse yield formation and sugar storage of sugar beet plants during an extended growing period to estimate whether sugar beet has the potential to generate the theoretically expected yield increase. From 2008 to 2012, pot experiments were carried out in the glasshouse with 11 sowing dates spread over the years with sequential harvests. The oldest plants were grown for 859 days (14 242 °Cd). Root fresh matter yield continuously increased till the latest harvest. In contrast, the sugar concentration reached an optimum value between 3400 and 5000 °Cd and then decreased with time. Despite longer growing periods, the number of cambium rings, which are regarded as essential for sugar storage, did not change. This points to an early and genetically fixed determination of the formation of cambium rings. Additionally, the rate of photosynthesis decreased concomitantly with the sugar concentration. In conclusion, there is some evidence that the sugar concentration of the storage root is limited by the sink capacity, which in turn controls the source activity by a feedback regulation of photosynthesis and leaf formation. The dry matter composition of the storage root changed towards lower sugar concentration and concurrent higher concentration of cell wall compounds (marc). The sugar yield still increased beyond a thermal time at which winter beets will probably be harvested in practice. Hence, the theoretical yield increase in autumn sown sugar beets can be realized, provided that the plants show sufficient winter hardiness and bolting resistance.

Specific leaf area development of autumn-sown sugar beet (Beta vulgaris L.) on different sowing dates in northern Germany

SUMMARYIn most regions, sugar beet is normally sown as a spring crop. If sown in autumn the crop remains on the field over winter and may achieve fast re-growth in spring from assimilates stored within the beet, allowing earlier leaf growth and light interception in spring. The specific leaf area (SLA) (ratio between leaf surface and leaf mass) is mainly affected by leaf area expansion and consequently affects productivity in early growth stages. The aim of the present study was (i) to examine the SLA dynamics of autumn-sown sugar beet before and after winter and (ii) to develop an empiric approach describing SLA changes during the growth period. A field trial in northern Germany with three different sowing times (mid-April, mid-June and mid-August) and varying plant densities (148 000, 246 000 and 370 000 plants/ha) was carried out in 2009/10 to 2011/12. The average SLA of the canopy was the highest (>25 m2/kg) directly after emergence, then decreased until autumn (<13 m2/kg) and increased again up to 20 m2/kg during re-growth of winter sugar beet in spring. A stepwise multiple regression analysis revealed mean photosynthetically active radiation over 10 days before measurement (PARmean), leaf area index (LAI), mean temperature over 10 days before measurement (Tmean) and temperature sum since sowing (Tsum) as the main influences on SLA dynamics. The strongest correlation to SLA was shown by Tmean (r = 0·69) and the weakest by Tsum (r = −0·28). A multiple linear regression model was fitted to the dataset with Tmean, PARmean and log (Tsum) achieving an adjusted R2 of 0·64. This empirical equation is suitable for use in a crop growth model for winter sugar beet.

Evaluation the effect of paclobutrazol on bolting, qualitative and quantitative performance in autumn sown-sugar beet genotypes in Moghan region

The response of sugar beet genotypes to different levels of paclobutrazol was studied during 2013-2014 as a split plot based on randomized complete block design with three replications. Treatments were paclobutrazol application at three levels (0, 150 ppm and 300 ppm) as main plots and sugar beet genotypes at six levels (Eudora, Giada, Jawaher, Levante, Vico and (FC607*474)*Pool-PC.F2-HSF60-P.3) as subplots. Bolting percentage, root yield, sugar content, root K and Na contents, amino nitrogen, molasses sugar percentage, gross sugar yield, extractable sugar yield, alkalinity factor, white sugar yield and extraction coefficient were estimated. Results indicated that bolting percentage, bolting height, sugar content, Na content, alkalinity factor, molasses sugar percentage, extractable sugar, white sugar yield and extraction coefficient were affected by the paclobutrazol levels. Overall, results highlighted the positive effects of paclobutrazol on bolting percentage reduction, content sugar and root quality improvement. A significant difference was found sugar beet genotypes in bolting percentage, root yield and sugar content.

Relevance of Osmotic and Frost Protecting Compounds for the Winter Hardiness of Autumn Sown Sugar Beet

AbstractThe cultivation of autumn sown sugar beet (winter beet) is supposed to result in a marked yield increase compared with spring sown sugar beet. Although the importance of the growth stage reached before winter for the survival of autumn sown sugar beet has already been shown, it is not clear to which extent osmotic and potentially frost protecting compounds may contribute to winter hardiness. The study thus aimed to analyse the acclimatization process of sugar beet to low temperatures and to identify compounds which are important for survival of frost. Field trials with autumn sown sugar beet were conducted at eleven environments in Germany from 2009/10 to 2012/13, which were accompanied by greenhouse experiments with controlled temperature regimes. In the field trials, the survival rates after winter varied from 0 % to 99 %, but only in four environments differences between the five genotypes occurred. During acclimatization, betaine, glutamine, proline and raffinose were markedly accumulated and osmolality was enhanced. In particular betaine, amino acids and osmolality showed a positive correlation to the survival rate and were thus identified as potentially frost protecting substances for sugar beet. In contrast, raffinose and proline seem to act rather as stress indicators as they were negatively related to survival. Possible frost protecting substances were identified which can be used in breeding to improve the winter hardiness of sugar beet.

Importance of growth stage and weather conditions for the winter hardiness of autumn sown sugar beet

The cultivation of sugar beet as a winter crop harvested in autumn of the next year is expected to contribute to a marked yield increase. Sown in autumn the plants have to survive frost during the winter. The study thus aimed to characterize the optimal growth stage, in which maximum winter hardiness is reached, and to determine the lowest temperature sugar beet plants can survive in this optimal growth stage. Furthermore, the importance of weather conditions (temperature, snow) in relation to the growth stage of the plants was assessed with a PCA (principle component analysis).From 2009 to 2012 field trials with 5 genotypes at 3 locations in Germany were conducted, which were accompanied by greenhouse experiments with controlled frost experiments. The survival rate after winter was mainly affected by the environment (year×location, 93%), while the genotype effect (1%) was rather low. An optimal growth stage for maximum survival was determined at a thermal time after sowing of 600–900°Cd (base temperature 3°C). The greenhouse experiments revealed that in this optimal growth stage the plants survived a minimum temperature of −7°C (−6°C to −8°C). In the field trials, the impact of the growth stage reached before frost (46%) on the survival rate after winter was considerably higher than the actual weather conditions during winter (17%). In particular too much advanced growth (dry matter yield of root and leaves, root diameter) resulted in a high susceptibility for frost damage. Regarding the weather conditions, the number of frost days with snow and the minimum temperature during winter without snow had the highest importance for survival.The knowledge of the required thermal time to reach maximum winter hardiness can be used to optimize the sowing date of autumn sown beets in different environments. However, a conflict may occur between the aim to obtain optimal winter hardiness and to reach maximum yield in the next year.

EcoTILLING in Beta vulgaris reveals polymorphisms in the FLC-like gene BvFL1that are associated with annuality and winter hardiness

BackgroundSugar beet (Beta vulgaris ssp. vulgaris L.) is an important crop for sugar and biomass production in temperate climate regions. Currently sugar beets are sown in spring and harvested in autumn. Autumn-sown sugar beets that are grown for a full year have been regarded as a cropping system to increase the productivity of sugar beet cultivation. However, for the development of these “winter beets” sufficient winter hardiness and a system for bolting control is needed. Both require a thorough understanding of the underlying genetics and its natural variation.ResultsWe screened a diversity panel of 268 B. vulgaris accessions for three flowering time genes via EcoTILLING. This panel had been tested in the field for bolting behaviour and winter hardiness. EcoTILLING identified 20 silent SNPs and one non-synonymous SNP within the genes BTC1, BvFL1 and BvFT1, resulting in 55 haplotypes. Further, we detected associations of nucleotide polymorphisms in BvFL1 with bolting before winter as well as winter hardiness.ConclusionsThese data provide the first genetic indication for the function of the FLC homolog BvFL1 in beet. Further, it demonstrates for the first time that EcoTILLING is a powerful method for exploring genetic diversity and allele mining in B. vulgaris.

Growth analysis of autumn and spring sown sugar beet

Slow leaf formation in spring is regarded as the main factor limiting sugar beet yield. It is therefore expected that yield can be enhanced when plants develop leaves earlier resulting in an extended growing period. The aim of this study was to analyse leaf and storage root growth of sugar beet plants sown in autumn or very early in spring with regard to possible yield increases. In 2005/06 and 2006/07, field trials were conducted at 4 sites with 6 sowing dates: August, beginning and mid of September, and in February, March and April. Sequential harvests were conducted to follow yield formation. Field emergence of autumn sown sugar beets was fast and reached 90% whereas in early spring it was severely restricted due to low temperature. Leaf and root yield formation of autumn and spring sown sugar beets could well be described with thermal time confirming that sugar beet growth is temperature driven and day length insensitive. Despite longer growing periods autumn sown beets did not form more cambium rings in the storage root than spring sown beets. That might be partly due to the bolting process after winter. However, early spring sown beets as well did not achieve more cambium rings than plants sown in April pointing to a presumably limited ability to adapt cambium ring formation. Because of the shift to reproductive growth, autumn sown beets formed high amounts of shoot dry matter, but not much root dry matter. Furthermore, the root dry matter consisted of a lower sugar and a higher marc content and would therefore not be suitable for sugar recovery. Earlier sowing in spring did not result in a significant yield increase because the benefit from early sowing diminished throughout the season as also obvious from the distance between the cambium rings. For bolting resistant sugar beet varieties, which are expected to be available in near future, the presented data form a basis to predict yield with models. However, it has to be investigated to what extent sugar beet growth and yield formation benefits from early sowing and extended growing periods.

Light absorption and radiation use efficiency of autumn and spring sown sugar beets

The cultivation of autumn sown sugar beets is expected to result in large yield increases due to more light absorption. The objective of this study was thus to analyse growth of autumn sown sugar beets with regard to (a) leaf development and light absorption and, (b) radiation use efficiency, the conversion of the absorbed light into dry matter. In 2005/06 and 2006/07, field trials were conducted at 4 sites with 3 sowing dates in autumn and 3 sowing dates in spring. The results show that the formation of leaf dry matter of autumn sown beets followed thermal time. A leaf area index of 3.5, and thereby canopy closure, was reached 3–4 weeks earlier than in spring sown beets resulting in extra absorption of light, in particular in April and May. Autumn sown beets produced 1.2 g dry matter per MJ solar radiation absorbed and thus, did not differ from spring sown beets in the radiation use efficiency. From light absorption and radiation use efficiency the possible yield of autumn sown sugar beets was estimated, provided these beets would not bolt after winter. Autumn sown beets could capture 2338 MJ solar radiation between sowing and harvest during October in the following year. Taking into account the improved light absorption, a theoretical yield increase of 26% compared to spring sown beets was calculated. It is discussed that yield formation of autumn sown beets would most likely be limited by the sink capacity and changes in the composition of the storage root. The data of these experiments will form a good basis for modelling yield formation of autumn sown sugar beets.

Effect of irrigation frequency on root water uptake in sugar beet

A 2-year trial was performed on autumn-sown sugar beet grown in pots in order to study the influence of irrigation frequency on the water used by plants along the soil profile. The outdoor pots, containing one plant each, were 1.3 m high and had circular openings, through which Time Domain Reflectometry (TDR) apparatus wave guides could be inserted. Three irrigation intervals were compared and plants were watered whenever the soil layer explored by roots had lost 30% (SWD1), 50% (SWD2) and 70% (SWD3) of the total available water (TAW). During the irrigation season, the water extracted by the plants from each layer along the soil profile (RWU) was determined by monitoring volumetric soil moisture content (θ), by TDR. At harvest time, root length density (RLD) along the soil profile was assessed using the Tennant method. The applied irrigation frequencies significantly affected the RWU. With the SWD3 protocol, irrigation was at longer irrigation intervals (9 days) and watering volumes were as high as 84 mm. In this treatment, the plants lost almost 60% of total water from the lower soil layer (0.6–1.0 m). In treatment SWD1, the irrigation interval was very short (3 days), and water extraction from 0.0–0.6 m soil depth was 92.0%. In the intermediate treatment, the irrigation interval was 5.5 days and a more uniform water depletion was observed along the root zone, approximately equal between the 0–0.6 and 0.6–1.0 m soil layer. Water extraction of sugar beet plants at the deeper soil layers in response to long irrigation intervals was related to an increase in water uptake efficiency of the deeper younger roots and not to an increase in root length density, which, on the contrary, decreased. This morpho-physiological acclimatization to progressive soil water deficit was coupled with an increase of the root/shoot ratio.

Sugarbeet (Beta vulgaris) response to residual soil N under Mediterranean agronomic practices

Autumn-sown sugarbeet (Beta vulgaris L.) responses (sugar yield, plant N-uptake and juice quality) were studied in relation to the residual NO3−-N in a soil of southwestern Spain which, for the previous five years (1989–93), had received high N rates, in accordance with conventional fertilization schedules used by farmers in the area. Three different combinations of fertilizers, supplying equal amounts of N, were used during the fertilization period (1989–93): a mineral fertilization treatment (MF, a complex 15N-15P2O5-15K2O) and two organo-mineral fertilization treatments (an olive mill wastewater sludge compost, AC, and a depotassified concentrated beet vinasse, V). All these treatments also received a top-dressing with urea (46% N). A control treatment (C), without fertilization was included for comparison.During the major part of the beet growing season, the presence of almost four times as much mineral N in the 0·100 cm soil layer of previously fertilized plots (AC, V and MF) than in the unfertilized one (C), led to a significant increase (P<0·05) in total fresh weight yield and N-uptake, but also to a significant decrease (P<0·05) in sugar content and beet processing quality. The time course of NO3−-N concentration in sugarbeet petioles and the evolution of the nutritional state of leaf-blades gave advance information about the final response of the crop to the different fertilization treatments. Besides N, Na was the element which, due to the repeated and high fertilization rates applied, had a major effect in reducing the technological quality of the sugarbeet.

An evaluation of the potential benefits and costs of autumn-sown sugarbeet in NW Europe

In NW Europe a major limitation to the yield of sugarbeet is development of the foliage canopy in May and June, too late to capture much of the available solar energy. This problem could be solved if the crop was sown during autumn so that the seedlings survived the winter and developed a large leaf canopy in early spring. This has led to a search for mechanisms to control flowering so that plants remain vegetative after the winter. However, there has been no serious attempt to estimate the effect of advanced canopy development on the likelihood of water stress. This study has used a combination of modelling of growth to predict yield of rainfed crops and an analysis of the literature to examine the likely consequences for pest and disease incidence if autumn sowing could be achieved without bolters. Compared to spring sowing, a potential yield advantage averaging 26% could be achieved, but this is likely to be overturned by any one of several beet-specific pathogens. For example, beet yellows virus would become more difficult to control and this has the potential to halve yield. Downy and powdery mildew and beet cyst nematode would be more expensive to control. The change from spring to autumn sowing would not allow harvest to be significantly earlier; this would be prevented by dry, strong soil conditions. Nevertheless, the increased emphasis on autumn work on arable farms would be costly.

Nitrogen uptake by autumn sown sugar beet

The influence of N fertilizer rate on uptake and distribution of N in the plant,15N labelled fertilizer uptake and sugar yield were studied for 3 years on autumn sown sugar beet (Beta vulgaris L.) under Mediterranean (Southern Spain) rain-fed and irrigated conditions. Available average soil N prior to sowing was 69 kg N ha−1, and net mineralisation in the soil during the growth period was 130 kg N ha−1. Maximum N uptake occurred in the spring and increased with increasing fertilizer rates in the irrigated crop. There was no increase in N uptake in the sugar beet cropped under rain-fed conditions because of water shortage. Maximum average N uptake both by roots and tops was between 200 and 250 kg N ha−1. When N fertilizer was not applied, average uptake from the soil was between 130 and 140 kg N ha−1. At the end of the growth period there was a marked translocation of N from the leaves to the root which increased with the N fertilizer rate. The N ratio top/roots at harvest was 0.45–0.5 and 0.8- - 1 in the irrigated and rain-fed sugar beet, respectively. Maximum15N labelled fertilizer uptake took place in May-June, being larger in irrigated sugar beet or when spring rainfall was more abundant. Fertilizer use efficiency varied between 30% and 68%. Sugar yield response to N fertilizer rates depended on the N available in the soil and on the total water input to the crop, particularly in spring. The response was more constant in the irrigated crop, where optimum yield was obtained with a fertilizer rate of 160 kg N ha−1. In the rain-fed crop, the optimum dose proved more erratic, with an estimated mean of 100 kg N ha−1. The amount of N required to produce 1 t of root and of sugar ranged between 1.5 and 3.8 kg N and between 11.1 and 22.4 kg N respectively, and varied according to the N fertilizer rates applied.

Growth and yield of autumn-sown sugar beet: Effects of sowing time, plant density and cultivar

Over a period of three years two trials were carried out on autumn-sown sugar beet ( Beta vulgaris L.), grown under normal Mediterranean climatic conditions, to study the influence on growth, yield and sugar quality of three sowing dates (October, November and December), two plants densities (100 000 and 80 000 ha −1 ) and three cultivars (Monauta, Monatonno and Kaweinterpoly). The weather influences dry matter accumulation and leaf growth. Sugar beet began active growth 160 days after sowing, at the end of winter, and achieved a maximum dry matter accumulation of 20–25 g m −2 day −1 and a leaf area index of 3.9–5. The earlier sowing produced a larger quantity of dry matter and more leaf growth and this resulted in higher root and sugar yields. Plant density of 100 000 plants ha −1 tended to produce better growth and higher yield than 80 000 plants ha −1 although the differences were not significant. No significant differences were noted between cultivars in any of the parameters measured. Net assimilation rate and crop growth rate values were similar to those obtained by others authors with spring-sown sugar beet, but relative growth rate and leaf area rate were lower. Optimum sugar yield and greater economic benefits for the farmer are obtained under Mediterranean conditions when the autumn-sown sugar beet is sown early in autumn at high plant density.

The effectiveness of carbamate and copper compounds in the control of Cercospora beticola Sacc. and their effects on yield and quality composition of autumn sown sugar beets

The fungicidal effectiveness of Zn-carbamate and copper compounds and their effects on yield and quality composition of autumn-sown beets were investigated under field conditions in a subtropical area.